Fish Fossils - Reply to Keith Littleton's POTM
Sean Pitman M.D.
Littleton's recent "POTM" on talk.origins. I have been busy with
other interests lately, but I finally decided to make a response.
Keith did raise some very good points. After considering these
points, I have some more questions that I present line-by-line as they
arise:
Message-ID: <fd67d42a.02092...@posting.google.com>
Sean...@juno.com (Sean Pitman M.D.) wrote:
-
> > Glenn Morton
> > I got to thinking about your fossil fish argument.
> > I even went to your web page where you discussed this
> > argument in detail. Really, it is a very interesting
> > argument. It seems quite reasonable. Like you said,
> > I haven't heard it discussed much. Given this, I do
> > have some questions or thoughts for you.
> >
> > I'm sure you know of the Coelacanth. The Coelacanth can
> > be found in the geologic column as far back as "360
> > million years" and as recently as "80 million years."
> > Then, it disappears from the fossil record entirely.
> > It was thought to have been completely wiped out with
> > the dinosaurs, until 1938 when living Coelacanths were
> > found alive and well off the east coast of S. Africa.
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> I know the "coelacanth". I know enough about them to know
> that the coelacanths found in Madagascar are neither the
> same type of coelacanth of fossils have been in rocks
> that are 360 million years ago nor the same type of
> coelacanth found in shallow marine strata that are about
> 80 million years old. The 360 million year old
> coelacanths are smaller, lack certain internal structures
> found in modern coelacanths and belong to a different
> genera and suborder. The modern coelacanths belong to a
> different genera than the 80 million year genera.
> technically speaking, the modern coelacanth of the
> genera Latimera, has no fossil record. Only the order
> and suborder that it belongs to has.
>
> If a person either goes to the nearest college library to
> research this topic or requests books by interlibrary
> loan, he / she can find:
>
> Coelacanth" W. W. Norton & Company, New York and
> London, 1991 ISBN 0-393-02956-5
>
> On page 78, last paragraph of that book, he would have read:
>
> "One point has to be emphasized; The living coelacanth
> is not a living fossil in the very strict sense that
> members of the species L. chaumnae itself have ever
> been found as a fossil. In fact, no other species
> assignable to the Genus Latimeria has been found as a
> fossil either. Latimeria and the Cretaceous fossil
> Genus Macropoma are quite closely related, and we
> could possibly include them in the same family. Beyond
> that, all fossil coelacanths belong to the order
> Coelacanthini."
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Kingdom: Anamilia
Phylum: Chordata
Class: Osteichthyes (bony fishes)
Order: Coelacanthini
Family: Sarcopterygii
Genus: Latimeria
Species: chalumnae
Very interesting comments. However, it seems to me that you over
emphasize the differences between the living species Latimeria
chaumnae, and the fossilized species. The statement above that "no
other species assignable to the Genus Latimeria has been found as a
fossil" seems to me to be a bit misleading. The fact of the matter is
that the skeleton of Macropoma lewesiensis, which is known from the
upper Cretaceous, is virtually identical to that of the coelacanths
caught off Sodwana Bay, Latimeria chalumnae, and differs little from
the skeleton of most Devonian coelacanths. (Forey, P. 1998. History of
the Coelacanth Fishes. Chapman & Hall.) There seems to be a tendency
to place very similar fossils in different categories based primarily
on the fact that they obviously lived so far apart in time that they
can't possible be members of the same species. This practice seems to
be the rule rather than the exception. So, to say that the L.
chaumnae species has never been found in the fossil record seems to me
to be stretching it a bit since this species classification is based
on very minor morphologic differences that are clearly within the
range of intra-species variation if the two fish were swimming side by
side today. It's kinda like putting the French and Italians in
different genus categories.
> > Why then did they disappear from the fossil record after
> > such a long presence there? Some argue that they used to
> > live in environments "conducive" to fossilization, but
> > now they live in caves and under the overhanging marine
> > reefs of volcanic islands that are not so conducive to
> > fossilization.
-
> This might be quite true, but there is a lack of such
> Tertiary, Mesozoic, or Paleozoic fossil bone beds that
> occur within sediments, which have accumulated in the
> caves and overhangs in reefs of volcanic islands. This
> is because these deposits have either subsided with the
> volcanic islands that they are associated with or have
> been subducted with the volcanic islands beneath
> continental plates. In the former case, the deposits
> associated with still extent volcanic islands are now
> underwater and buried beneath younger sediments that
> have continue to accumulate on top the islands as they
> sank. In the latter case, fragments of some volcanic
> islands have been scraped off during subduction, but
> for the most part, these fragments are badly mangled and
> metamorphosed to the point of badly mangling, even
> destroying any fossils that they might contain.
>
> Similarly, the deep sea sediments that might contain the
> fossils of coelacanths also have been largely subducted
> with slices and slivers of these being sediments being
> plastered against the continental margin just as mangled
> and metamorphosed as the volcanic islands. The deep sea
> sediments that are still undeformed lie at the ocean
> bottom and buried under younger sediments where nobody
> can get at them.
-
The subduction argument has been used to explain a lot of things and
it may in fact explain the absence of fossils from fish who preferred
living in volcanic caves and overhangs in very deep ocean habitats.
However, it seems like the theory of subduction itself is not
completely without its flaws. Evidence of significant subduction as a
means for sediment removal seems to be rather lacking as far as I can
tell. There is even argument as to what forces might be stable enough
to drive such prolonged subduction of huge portions of the earth's
crust over the course of hundreds of millions of years. In any case,
there have been recent finds of coelacanths off the coast of the
Comoro Islands in 1998 that do not live in very deep water (~200m) or
in caves. How did these coelacanths survive without being fossilized
over the course of 80 million years?
> > Interesting argument I think.
-
> It is interesting. I would be very interested in why Mr.
> Pitman expects paleontologists to be able to find fossils
> in sediments that are either underwater and buried
> beneath younger sediments or consist of badly deformed
> even metamorphosed sediments. If this argument is invalid,
> Mr. Pitman should have absolutely no trouble at all
> pointing specific outcrops of sedimentary strata where
> a person could look for the remains of coelacanths.
-
The vast majority of sedimentary layers in the geologic column were
formed underwater. I am rather surprised that anyone would argue this
point. For example, it is thought that all of the layers in the Grand
Canyon, save the Coconino Sandstone layer, was formed underwater.
Yet, there it is for all to see, above water. The coelacanths that
are fossilized, also lived underwater once upon a time. The argument
here is that their habitat was more conducive to fossilization than
the habitat of the modern coelacanths. Conduciveness is a bit
different from preservation potential however. Subduction arguments
do not argue so much against conduciveness, but against preservation
potential. However, we do have supposedly ancient deep sea sediments
preserved in the fossil record. Somehow they managed to survive
destruction by subduction. In any case, more populations of
coelacanths have been found that live in shallower waters that are not
protected by deep sea caves. Yet, these fishes somehow avoided
fossilization as well. This seems rather strange to me. Of course,
coelacanths are not the only ones to seemingly be raised up after tens
of millions of years of extinction. There are a large number of other
fossils to include entire orders of creatures that disappear from tens
of millions of years, and then reappear suddenly in the fossil record.
These examples are so common that they have been given the name,
"Lazarus Taxa."
> > Fossilization requires rapid burial or else decay will
> > obliterate all traces.
-
> This is not completely true. Bones can survive for over
> a year before being buried.
This depends upon the environment in which they are deposited as well
as the size of the bones. Also, well preserved fossils of completely
intact specimens, to include soft tissue impressions in fine detail,
as is the case with many of the coelacanth fossils, requires rapid
burial.
> In the case of shells, they
> can be washed around for decades, even hundred of years,
> before they are finally buried in the sediment to become
> fossils.
This also depends upon the environment and the size of the shell. The
fact of the matter is, even in the best of circumstances, even shells
are degraded fairly rapidly in exposed environments. They do not last
for hundreds of years of open exposure and weathering. In any case,
we are not talking shells here, but fish that are preserved intact,
often with delicate soft tissue impressions also preserved in fine
detail. This level of detail requires very rapid burial.
> Only in of the fossilization of soft parts is
> immediate burial required.
At least at this level, but also at the level of intact skeletons.
> This all has been documented
> by direct field observation and other studies. Contrary
> to what Mr. Pitman incorrectly claims, the hard part of
> animals can persist for a significant period of time
> before being finally buried.
Generally not. Even "hard parts" weather fairly rapidly in open
environments. Intact skeletons are especially prone to
disarticulation.
> In fact, the degree to which
> many fossil shells are either encrusted or have been
> bored by other organisms and bones show signs of either
> weathering or gnawing demonstrates that they were not
> rapidly buried before being fossilized.
Encrustation and boring can occur very rapidly after death and even
before the death of shelled creatures. Encrustation is quite commonly
observed in living animals that walk along with entire colonies of
other types of creatures living on their backs. Keeping a shell clean
of critters is a constant battle for the owner of a shell. The fact
that there are a significant percentage of fossilized shells preserved
in pristine condition speaks in favor of their rather rapid burial, en
mass.
> Of course, a
> bone or shell eventually has to be buried to be
> preserved.
-
> > It seems to me that fossilization is catastrophe
> > dependent.
-
> At this time, enough research has been done by geologists
> and paleontologists where the proposal that fossilization
> is catastrophe dependent can easily be demonstrated to be
> completely refuted.
>
> For example, in case of the preservation of bone,
> catastrophes have nothing to do fossilization. Location
> instead of catastrophe is an important part of whether
> a bone becomes preserved. A person need only look at the
> abundant fossil bones found in the Pleistocene to
> Holocene age fluvial sediments that underlie Yellow House
> Draw and many other stream and river valleys in the
> Southern High Plains of Texas and New Mexico (Holiday
> 1997).
>
> The bones of bison and other animals that fell on the
> uplands of the Southern High Plains between river
> valleys have decayed away. In these uplands, they either
> lay exposed on the surface where weathering and
> scavengers destroyed them.
>
> However, where the bones of these bison and other animals
> died upon the active floodplains of rivers and streams,
> the bones of a number of them were eventually buried in
> the sediments and some of these were indeed preserved. No
> catastrophe was involved. Rather, the day to day, year to
> year accumulation of sediments in lakes, in rivers, on
> floodplains, and as dunes in these river valleys buried
> and preserved these fossils. These fossils range in age
> from bison contemporaneous with the colleagues of Buffalo
> Bill to bison hunted by successive generations of Native
> Americans back to Folsum and Clovis cultures and
> mammoths, horses, and megafauna predating the Clovis
> cultures. These bones consists of both natural bone beds
> and kill sites. In the bottoms of Yellowhouse,
> Blackwater, and other draws in the Southern High Plains
> is an abundance showing that that the statement
> "fossilization is catastrophe dependent" is
> scientifically bankrupt. In these draws, fossils have
> been constantly formed for the past 12,000 years without
> any need for imaginary catastrophes. In case of
> Yellowhouse Draw, the occasional deposition of fluvial,
> lacustrine, and wind blown sediments along with very
> calcareous soils is enough for fossils to have been
> created over a long period of time (Holiday 1997).
You evidently fail to see the context of my statement that,
"fossilization is catastrophe dependent." The context was a
discussion of intact fish fossils. Fish simply do not lay on the
surface of the ocean floor very long and remain intact if they are not
buried quickly. The fossilized disarticulated bones of bison in river
valleys is hardly the issue. The fossil record shows clear evidence
of catastrophic burial on a huge scale. Catastrophic burial and
fossilization is the rule and not the exception in the fossil record.
Mass graveyards with bones piled thickly together are seen as well as
millions of well preserved shells and fish all fossilized together...
to include soft part preservation. The same is true for plants.
Fossilized trees also generally show evidence of watery transport and
rapid burial.
< snip long list of references which may be found at talk.origins >
> > From my understanding, practically all fossils of fish
> > show evidence of catastrophic burial... en masse. In
> > other words, the fish were alive and well when they were
> > suddenly buried alive.
-
> If Mr. Pitman would research the fossilziation of fish,
> he would find the statement "practically all fossils of
> fish show evidence of catastrophic burial" to be a rather
> gross exaggeration of what the facts show. For example,
> the research by Maisey (1991) of the origins of the
> Santana fossil fish clearly demonstrates the lack of
> catastophe in their formation. Rather, they represent
> fish that died and sank to the bottom of a large anoxic
> lake over a period of thousands of years. The decay of
> the fish on the bottom precipitated carbonate minerals
> that preserved them as fossils.
In modern times, how often do you see this picture proposed by Maisey
happening? Fish simply do not fossilize in modern "anoxic lakes" like
they did in the past. Some pictures of the Santana Fossils can be
seen at:
http://www.uoguelph.ca/zoology/rush/zoo402www/ichthyology7.html
They are surprisingly well preserved. They show excellent scale, fin,
and eye socket preservation. This seems rather strange to me because
many fish float when they die and rapidly decompose, even while
sinking. The scales are the first to go. They are also heavily
scavenged before there is a chance to be buried if burial does not
occur rapidly. A description of how these fish were fossilized in
this Brazilian lake reads, "Rhacolepis lived in a shallow marine
environment. Fossil specimens found today were fish that died and were
quickly covered with silt or mud. That mud or silt hardened over
millions of years and the fossil remains of those fish are found in
limestone nodules, completely preserved in 3 dimensions. These fish
had a pointed skull, small sharp teeth, and small rhomboidal scales."
As it turns out, the Santana "lake" was not thought to be "anoxic" at
all. Here is a description of this "environment": In the Early
Cretaceous period the Santana Formation was deposited in warm,
shallow, salty lagoons close to land."
Clearly then, the generally pristine condition of the fossilized fish
in the Santana Formation speaks for a very rapid burial of living or
very recently killed fish. The Santana Formation of Brazil contains
fish whose gills and muscles are so perfectly preserved that
geologists believe they were fossilized within five hours of death.
The foremost expert on these Brazilian fossils, Dr David Martill, has
called this "the Medusa effect", after the creature of Greek mythology
who could instantly turn people to stone just by looking at them.
> In case of the fossil
> fish found in the Old Red Sandstone of Scotland, studies
> by Trewin and Davidson (1995) demonstrated that these
> fossils are not the result of some mythical catastrophe.
> Instead, the fish died when the lake they lived in dried
> up and as the fish decayed in muddy bottom of the lake,
> carbonate mineral precipitated around them and preserved
> them as fossils.
Old Red Sandstone in England has billions upon billions of fish,
spread over 10,000 square miles, with as many as a thousand fish
fossils in one square yard. Trewin and Davidson also note a high level
of soft part preservation to include markings of internal organs as
well as eyes. I fail to see how this level of preservation is
possible without very rapid burial. Also, calcium carbonate can
precipitate without water evaporating. For example, an unusual
combination of natural processes can take place to form the mineral
travertine. The process begins when water becomes elevated in
dissolved CO2(g) through interactions with the soil zone, carbonate
aquifers, organic material, or regional geothermal activity. Upon
emerging, the carbon dioxide outgasses as the water begins to
equilibrate with atmospheric conditions. This outgassing results in an
increase of calcite (CaCO3) in the water above saturation. Increased
calcite concentration eventually surpasses a critical level of
supersaturation and CaCO3 begins to precipitate as travertine.
Precipitates can occur on both organic or inorganic substrates. The
rapid burial of mass quantities of organic material, as if found in
the Old Red Sandstone formation, would produce very large quantities
of CO2.
> Finally, there are cases of massive fish
> kills resulting in the accumulation of entire schools of
> fish at the bottom of a lake where they were eventually
> buried. However, as documented by Weigelt (1989) way back
> in 1927, fish kills occur without the need for any
> catastrophe.
Yes, fish kills can occur without any deluge-type catastrophe.
However, massive fish kills in oceans and lakes do not generally
result in fossilization nor are they preserved in fine detail as we
see in the massive fish kills of the fossil record.
> Having sailed and fished the bays, bayous, and rivers
> of Louisiana, I can personally vouch that natural fish
> kills involving entire shoals of fish are quite common
> in nature. In them, the fish die in a state of agony
> without the need of a catastrophe. This observation is
> documented in numerous published papers. As Weigelt
> (1989, page 163) observes:
No one is questioning this fact. I have personally observed massive
fish kills myself. The question here though is if these massive fish
kills result in massive fossilization beds as we see in the fossil
record. As far as I can tell the answer is no. Why? because the fish
in these massive fish kills rapidly decompose before they have a
chance to be buried. In order to preserve the fine detail that we see
in the fossil fish kills of the past, rapid burial is required.
> "Reports of enormous fish kills are plentiful: Almost
> every ten years, a red mite appears in Walvis Bay,
> South Africa and causes a fish kill of such magnitude
> that the water is said to be completely covered with
> dead fish.
Again, were these fish kills fossilized? I think not. Not only do
you have to present how massive quantities of fish can all die
together, but also how they can all be fossilized in relatively good
condition... by slow burial. This has not been observed. This sort
of fossilization simply requires a rapid burial event.
> Poisoning by minerals and gases have likewise often
> been observed. Another example is the massive die-
> off of fish during the iron "bloom" in Siberian rivers,
> which Baron von Toll has reported in detail. In west
> Texas and in many other areas, when the water level in
> the rivers is low, there is a bloom of algae, and vast
> numbers of fish die from carbon dioxide poisoning.
> Changes in salinity very frequently cause fish to die.
> Freyberg (55) observed in Mar Chiquita, Argentina (a
> basin of concentrated salt solution into which,
> however, a completely isolated source of fresh water
> emptied) large accumulations of fish that had died
> and been preserved by the salt solution and had then
> floated ashore, where they were mummified. Freshwater
> fish in coastal lakes die off when there is an ingress
> of salt water. The most well-known instance occurred
> when the narrow neck of land that separated the
> Limfjord from the ocean to the west broke in 1825.
> After a storm tide, salt water entered and killed all
> the freshwater fish, which floated ashore in
> unbelievable numbers; some were even buried along with
> eelgrass beneath the sand carried ashore by the
> storm tide."
Were they fossilized in mass?
> Weigelt (1989, page 164) also observed:
>
> "Andree (9) reports on the natural mass death of the
> fish Mallotus villosus Muller, which occurs annually
> after the breeding season and which, ac cording to A.
> Jort, regularly coincides with radical temperature
> changes in the Barents Sea. The floors of calm bays
> and inlets of the harbors at Disko and Lodden,
> Greenland, can be completely covered with fish
> carcasses. Remains of Mallotus villosus form the growth
> centers of concretions known as 'marlekor' found in the
> late glacial, polar sea clays in Greenland and Norway."
Again, do these dead fish mats fossilize en masse? Nope. Not unless
they are rapidly buried.
> If a person looks at the taphonomy and sedimentology of
> the fossil fish beds in detail, the evidence for them
> having been formed catastrophically either turns out to
> be wishful thinking or not credible evidence at all of
> any catastrophe having created them.
I disagree. Evidence for rapid or catastrophic burial seems clearly
evident.
> References cited:
>
> Maisey, John G. (1991) Fossil forensics. In J. G.
> Maisey, ed., Santana fossils; an illustrated atlas.
> T.F.H. Publ.. Neptune City, New Jersey.
>
> Trewin, N. H., and Davidson, R. G. (1995) An Early
> Devonian lake and its associated biota in the Midland
> Valley of Scotland. Transactions of the Royal Society
> of Edinburgh: Earth Sciences. vol. 86, Part 4,
> pp. 233-246.
>
> Weigelt J. (1989) Recent Vertebrate Carcasses and their
> Paleobiological implications. University of Chicago Press.
> Chicago, Illinois.
-
> > There are even some fossils of fish in the middle of
> > eating other fish.
>
> There two problems here. First, these fossils are very
> extremely rare. So rare, that they are only indicative of
> very rare events.
Just imagine how many fish are eating other fish at any one moment in
time. A relatively small percentage... right? Considering this, the
fact that we have fossils of this event frozen in time is pretty
amazing indeed. We would expect a relatively few examples given a
catastrophic scenario.
> Finally, these fossils only demonstrate
> how some Young Earth creationists are incapable of
> recognizing a fish that choked on trying to eat a fish
> far larger than it could swallow.
-
Really? The fish choked to death? Then both of the fishes drifted
down to the bottom of the lake and were perfectly preserved somehow
without any significant evidence of decay or predation? Come on now.
How often do you see fish choking on other fish today? Have you ever
seen a fish choking on another fish that it is trying to eat? But
hey, lets just say that it can happen. A fish can have eyes bigger
than its mouth. It tries to eat something that is just too big to
handle. Its meal gets stuck and its gills get blocked, and so it
suffocates to death. However rare this event might be, how rare would
it be for these two struggling fish avoid being eaten by some other
predator or scavenger before they became buried in the scavenger rich
mud at the bottom? Really, how rare would this be? I doubt it would
ever happen once in ten million years without some sort of rapid
burial event occurring at exactly the same time.
> > Also, many of them show statistically significant
> > alignment with each other. In other words, they are
> > generally found in the same plane of orientation such
> > as would be expected from a current deposit.
-
> Bottom currents are not unique to catastrophes. There
> are currents at the bottom of lakes, streams, and so
> forth.
Not generally as widespread as we see in the fossil record.
> Just a regular flood will create such
> orientations.
That's true.
> Also, you greatly exaggerate the degree
> that such fossil deposits show orientations. For
> example, the Santana fossil deposits and the Old Red
> Sandstone fossil fish don't show such orientations.
> Many of the Miocene diatomite fossil fish don't show
> such orientation. Basically, the presence of a current
> is **not** evidence of a catastrophe and **not** all
> fossil fish deposits even show the alignment and
> orientation that indicated the presence of a current.
-
How did I "greatly exaggerate" by saying that "many of them show"
alignment? I certainly did not say that all of them or even most of
them showed alignment. However, many fossils do show alignment with
each other... especially larger fossils, like dinosaurs and trees.
However, even smaller fossils such as shells, leaves and fish can and
often do show stream orientation. Does this, by itself, mean that
they were buried catastrophically? No. The evidence for sudden
burial is found in the condition of the specimens themselves. Stream
orientation, when present, only helps to show that these animals
probably didn't die and sink slowly to the body of some still, anoxic
lake bed, to be gradually buried over an extended course of time.
> > The same orientation can be generally seen with other
> > types of fossils such as plants, shells, dinosaurs, etc.
-
> Some of the bone beds in the fluvial sediments underlying
> Yellowhouse Draw near Lubbock, Texas in Southern High
> Plains show the exact same type of orientation. It would
> be foolish to argue that because these bones are
> oriented, that they were deposited by a catastrophe.
> They, like the oriented dinosaur bones and plants are
> not oriented because of a catastrophe. Rather, they just
> were by the currents of either the river or flood that
> moved them around and preserved them by dumping sediments
> on them.
-
Ok, if you don't want to call stream orientation catastrophic, that's
fine with me. But, the fact remains that water currents were involved
with many of these fossilized burials... sometimes on a massive scale.
> > How then did the Coelacanth avoid such catastrophic
> > burials when it hadn't been able to avoid them for
> > hundreds of millions of years?
-
> There weren't any catastrophic burials. The problem is
> that very little of the rock, in which the fossils of
> coelacanth would occur, is available for people to find
> their fossils in.
That's a fine theory, but again, the coelacanth is not the only
creature to emerge almost unchanged from tens of millions of years of
extinction. Also, coelacanths have now been found who's habitat is
not "protected" by caves and overhangs or extreme depths. The
Latimeria manadoensis is "almost identical" both in phenotype and
maybe even habitat the Macropoma lewesiensis. So how did the L.
manadoensis avoid fossilization over 80 million years? Maybe poor
environment for fossilization? Maybe, along with many other "Lazarus
Taxa" who seem to be able to avoid fossilization the same way?
> Also, with a relatively small numbers
> of coelacanths, their fossils would be very hard to find
> even if large amounts of these rocks were available for
> inspection.
-
Perhaps. But over the course of 80 million years, with millions of
generations of coelacanths and population fluctuations, it still seems
pretty impressive to me that they avoided fossilization so well.
> > With these thoughts in mind, let me pose a hypothetical
> > for you to shoot down (That's the whole point of
> > hypothetical questions you know... to be shot down. That
> > is the goal of the scientific method. Once a person stops
> > trying to shoot down hypothesis and theories of
> > science, science is not longer science.).
> > What if the fish found in the lower layers of the geologic
> > column were "sorted" according to various factors such as
> > environmental habitat and body composition (to include
> > size, shape, and density)?
-
> ....stuff about hydraulic sorting omitted...
>
> What I would like to know is how hydraulic sorting can
> distribute intact fossil reefs throughout the entire
> geological column.
How do you know that they are "intact"?
> How does hydraulic sorting explain
> the biostratigraphy of microfossils?
Hydraulic sorting doesn't explain the biostratigraphy of microfossils.
There are other ways that sorting can happen you know. The natural
habitat itself acts as a sorter. Also, the same species can have a
different look in different environments. Phenotypic variation does
not always depend upon genotypic change, but can often change in tune
with changing environmental needs. Such changes that are based in
environmental changes are called, "ecophenotypic variations."
Microfossils, such as foraminifers, demonstrate a wide variety of
ecophenotypes. In fact, many phenotypes that were once thought to
represent different species groups are now known to represent
difference phenotypic variations within the same species.
> What I would like Young Earth creationists to explain is
> why microfossils which lived in the same ocean are so
> nicely stratified according to age. First go read
> "Microfossil Stratigraphy Presents Problems for the
> Flood" by Glenn R. Morton at:
>
> http://www.glenn.morton.btinternet.co.uk/micro.htm
>
> He gives a few of innumerable examples where foraminifera
> and other microsfossils are found in the same stratigraphic
> sequence over large areas, even world-wide. A person cannot
> explain this in terms of either location or habitat zonation.
Actually, a person can explain this in terms of both location as well
as habitat zonation.
> Since they are essentially the same size and weight,
> hydraulic sorting cannot be used as an explanation.
Yes, that's generally true.
> The
> only explanation is that the foraminifera are found neatly
> zoned by depth is because they lived at different times as
> the strata accumulated.
Well, this is not the only possible explanation.
> The Young Earth creationist global flood model cannot
> account for vertical distribution of microsfossils as
> illustrated in the "MMS GOMR Resource Evaluation
> Paleontological Laboratory, Biostratigraphic Chart." with
> a link at "Scientific and Technical Papers of the Gulf of
> Mexico OCS Region" at:
>
> http://www.gomr.mms.gov/homepg/whatsnew/papers/papers.html
>
> This chart can be downloaded from:
>
> http://www.gomr.mms.gov/homepg/whatsnew/papers/biochart.pdf
> http://www.gomr.mms.gov/homepg/whatsnew/papers/biochart.cdr
>
> This chart shows the vertical sequence in which all over
> the entire northern Gulf of Mexico how over a 100 different
> microfossils occur within a pile sediments over 15,000 to
> 20,000 feet thick. In oil well after oil well and in
> surface exposure after surface exposure, the sequence of
> microfossils shown in this chart can be found. For
> example, Hyalina "B" is always found in the sediments
> above the sediments containing Angulogerina "A." It, in
> term, overlies sediments containing Cristellaria "S",
> Globorotalia miocenica and Globorotalia menardii, and
> Bolivina imporcata. These microfossils are found
> above sediments containing Lenticulina 1, Cassidulina "L",
> and Saracenaria "H". In addition, the geologic periods
> also occur in the same order in oil well after oil well
> as well as in surface exposures. Hydraulic sorting cannot
> explain this vertical distribtion of microfossils as Glenn
> argues on his web page.
Hydraulic sorting is not needed to explain these phenotypic
distributions. Tammy Tosk, also a geologist, disagrees with Glenn
Morton's conclusions. She describes how foraminifers can be sorted
according to other factors besides hydraulic sorting such as ecologic
zonation. Her discussion can be found at:
http://www.grisda.org/origins/15008.htm
> Have Fun
> Keith Littleton
> New Orleans, LA
You too ; )
Sean
Pokemoto
>Path:
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reader.com!newsfeed.media.kyoto-u.ac.jp!logbridge.uoregon.edu!newsfeed.sta
nford.edu!darwin.ediacara.org!there.is.no.cabal
>From: Sean...@juno.com (Sean Pitman M.D.)
>Newsgroups: talk.origins
>Date: Sun, 24 Nov 2002 23:17:48 +0000 (UTC)
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>
SNIP:
>Very interesting comments. However, it seems to me that you over
>emphasize the differences between the living species Latimeria
>chaumnae, and the fossilized species. The statement above that "no
>other species assignable to the Genus Latimeria has been found as a
>fossil" seems to me to be a bit misleading. The fact of the matter is
>that the skeleton of Macropoma lewesiensis, which is known from the
>upper Cretaceous, is virtually identical to that of the coelacanths
>caught off Sodwana Bay, Latimeria chalumnae, and differs little from
>the skeleton of most Devonian coelacanths. (Forey, P. 1998. History of
>the Fishes. Chapman & Hall.) There seems to be a tendency
>to place very similar fossils in different categories based primarily
>on the fact that they obviously lived so far apart in time that they
>can't possible be members of the same species. This practice seems to
>be the rule rather than the exception. So, to say that the L.
>chaumnae species has never been found in the fossil record seems to me
>to be stretching it a bit since this species classification is based
>on very minor morphologic differences that are clearly within the
>range of intra-species variation if the two fish were swimming side by
>side today. It's kinda like putting the French and Italians in
>different genus categories.
There is all one small problem with this. We have the Coelacanth mitochondrial
sequence and guess what? it is exactly what we predicted it would be. This
means that this sequence has been evolving for hundreds of millions of years
from the common ancestor of mammals and lobefin fish. You have to explain why
the sequence is what we predict if evolution were true. Why would lobefin fish
be more closely related to land vertebrates than teleosts like Carp? Why are
the branch lengths what we would predict if we shared a common ancestor with
lobefin fish? Ooops, you can't explain this data, but biological evolution
can. What is your prediction of what the sequence should be? Why doesn't your
prediction match with reality?
And it just isn't Coelocanths. We have living representitives of jawless fish
and guess where the DNA sequence puts them? We have boneless cordates and
guess where the DNA sequence puts them?. The morphologists didn't have DNA
data when they came to their conclusions. Why is the DNA data consistent with
their evolutionary predictions?
DNA data backs up the predictions for fish to land vertebrate evolution. No
matter how you nit pick the data you can't get around that fact. If we didn't
have these living fossils you'd have more to complain about, but don't complain
about something that destroys your own argument. If we had a couple of living
representitives of dinosaurs we could end the bird-dino debate. Extinction
bites, but we are all very glad when we still have a living representitive to
work with, so we don't have to guess anymore.
Ron Okimoto
R. Baldwin
news:fd67d42a.0211...@posting.google.com...
[big snip]
> The subduction argument has been used to explain a lot of things and
> it may in fact explain the absence of fossils from fish who
preferred
> living in volcanic caves and overhangs in very deep ocean habitats.
> However, it seems like the theory of subduction itself is not
> completely without its flaws. Evidence of significant subduction as
a
> means for sediment removal seems to be rather lacking as far as I
can
> tell. There is even argument as to what forces might be stable
enough
> to drive such prolonged subduction of huge portions of the earth's
> crust over the course of hundreds of millions of years. In any
case,
> there have been recent finds of coelacanths off the coast of the
> Comoro Islands in 1998 that do not live in very deep water (~200m)
or
> in caves. How did these coelacanths survive without being
fossilized
> over the course of 80 million years?
[huge snip]
I have personally seen and felt the overwhelming evidence for the
theory of subduction. In the Pacific Northwest, we have a volcanic
mountain range (the Cascade Mountains) running parallel to an ocean
trench about 50-miles distant, as is found in other parts of the
world. We find evidence of earlier, extinct volcanic ranges parallel
to evidence of older ocean shores. We find partially metamorphosed
ocean sediment in the Cascades. We have earthquakes. We have uplifted
ocean floor along the coast, where we can see pillow basalts that
formed underwater. We have trench filling thrust up to form the
Olympic Mountain range. Your suggestion that the theory of subduction
is flawed is simply laughable.
Bobby D. Bryant
> "Sean Pitman M.D." <Sean...@juno.com> wrote in message
> news:fd67d42a.0211...@posting.google.com...
>
>> The subduction argument has been used to explain a lot of things
>> and it may in fact explain the absence of fossils from fish who
>> preferred living in volcanic caves and overhangs in very deep
>> ocean habitats. However, it seems like the theory of subduction
>> itself is not completely without its flaws.
...
> Your suggestion that the theory of subduction is flawed is simply
> laughable.
Evolution-denial seems to require a commitment to chain in denials
of all the other branches of science as well.
Bobby Bryant
Austin, Texas
Greg
snipsnip
>
> Very interesting comments. However, it seems to me that you over
> emphasize the differences between the living species Latimeria
> chaumnae, and the fossilized species. The statement above that "no
> other species assignable to the Genus Latimeria has been found as a
> fossil" seems to me to be a bit misleading. The fact of the matter is
> that the skeleton of Macropoma lewesiensis, which is known from the
> upper Cretaceous, is virtually identical to that of the coelacanths
> caught off Sodwana Bay, Latimeria chalumnae, and differs little from
> the skeleton of most Devonian coelacanths. (Forey, P. 1998. History of
> the Coelacanth Fishes. Chapman & Hall.) There seems to be a tendency
> to place very similar fossils in different categories based primarily
> on the fact that they obviously lived so far apart in time that they
> can't possible be members of the same species. This practice seems to
> be the rule rather than the exception. So, to say that the L.
> chaumnae species has never been found in the fossil record seems to me
> to be stretching it a bit since this species classification is based
> on very minor morphologic differences that are clearly within the
> range of intra-species variation if the two fish were swimming side by
> side today. It's kinda like putting the French and Italians in
> different genus categories.
Here's a picture of each:
http://www.scienceinafrica.co.za/2002/february/coela2.htm
Not that I have any qualifications or training in comparative anatomy
but they look enough alike to be coelacanths but the snout looks much
different. I wouldn't expect them to be classified as the same
species. Coelacanths didn't change much over 380 million years yet
they are different enough to be classified into several genera.
>
>
snip
My friend had an oscar with some catfish in an aquarium. Though they
were about the same size when he started, eventually the oscar decided
to eat one of the catfish. Catfish have spines in their pectoral fins
that are extended when they are seized. The oscar survived for a day
or two with the catfish in its mouth. My friend was able to save the
catfish after the oscar died. I expect that sort of thing happens
quite a bit or catfish wouldn't have those fins.
>
snip
>
> Perhaps. But over the course of 80 million years, with millions of
> generations of coelacanths and population fluctuations, it still seems
> pretty impressive to me that they avoided fossilization so well.
How do you know they have avoided fossilization? How long does it take
for deep water sedimentary rocks to become strata of dry land where
fossils can be found? 80 million years (less for younger fossils) does
not seem all that long for that.
snip
> > Have Fun
> > Keith Littleton
> > New Orleans, LA
>
>
> You too ; )
> Sean
--
Greg
How do people who don't believe in evolution explain their cravings
for banana sandwiches?
Adam Marczyk
> Littleton's recent "POTM" on talk.origins. I have been busy with
> other interests lately, but I finally decided to make a response.
> Keith did raise some very good points. After considering these
> points, I have some more questions that I present line-by-line as they
> arise:
[snip]
> > "One point has to be emphasized; The living coelacanth
> > is not a living fossil in the very strict sense that
> > members of the species L. chaumnae itself have ever
> > been found as a fossil. In fact, no other species
> > assignable to the Genus Latimeria has been found as a
> > fossil either. Latimeria and the Cretaceous fossil
> > Genus Macropoma are quite closely related, and we
> > could possibly include them in the same family. Beyond
> > that, all fossil coelacanths belong to the order
> > Coelacanthini."
>
> Kingdom: Anamilia
> Phylum: Chordata
> Class: Osteichthyes (bony fishes)
> Order: Coelacanthini
> Family: Sarcopterygii
> Genus: Latimeria
> Species: chalumnae
>
> Very interesting comments. However, it seems to me that you over
> emphasize the differences between the living species Latimeria
> chaumnae, and the fossilized species. The statement above that "no
> other species assignable to the Genus Latimeria has been found as a
> fossil" seems to me to be a bit misleading. The fact of the matter is
> that the skeleton of Macropoma lewesiensis, which is known from the
> upper Cretaceous, is virtually identical to that of the coelacanths
> caught off Sodwana Bay, Latimeria chalumnae, and differs little from
> the skeleton of most Devonian coelacanths. (Forey, P. 1998. History of
> the Coelacanth Fishes. Chapman & Hall.)
Even if what you say is true, and Greg's post seems to show that the
morphological variation between the two species is actually fairly significant,
then so what? Evolution does not require that species constantly change in
appearance.
[snip]
> This practice seems to
> be the rule rather than the exception. So, to say that the L.
> chaumnae species has never been found in the fossil record seems to me
> to be stretching it a bit since this species classification is based
> on very minor morphologic differences that are clearly within the
> range of intra-species variation if the two fish were swimming side by
> side today. It's kinda like putting the French and Italians in
> different genus categories.
You seem big on that whole "intra-species" variation thing. Do you think the
"minor morphological differences" between, say, a tuna and a carp are small
enough to justify defining them as the same species? How about between a lion
and a tiger? A dog and a cat? (What are the morphologic differences between dogs
and cats, anyway?)
[snip]
> > This might be quite true, but there is a lack of such
> > Tertiary, Mesozoic, or Paleozoic fossil bone beds that
> > occur within sediments, which have accumulated in the
> > caves and overhangs in reefs of volcanic islands. This
> > is because these deposits have either subsided with the
> > volcanic islands that they are associated with or have
> > been subducted with the volcanic islands beneath
> > continental plates. In the former case, the deposits
> > associated with still extent volcanic islands are now
> > underwater and buried beneath younger sediments that
> > have continue to accumulate on top the islands as they
> > sank. In the latter case, fragments of some volcanic
> > islands have been scraped off during subduction, but
> > for the most part, these fragments are badly mangled and
> > metamorphosed to the point of badly mangling, even
> > destroying any fossils that they might contain.
> >
> > Similarly, the deep sea sediments that might contain the
> > fossils of coelacanths also have been largely subducted
> > with slices and slivers of these being sediments being
> > plastered against the continental margin just as mangled
> > and metamorphosed as the volcanic islands. The deep sea
> > sediments that are still undeformed lie at the ocean
> > bottom and buried under younger sediments where nobody
> > can get at them.
>
> The subduction argument has been used to explain a lot of things and
> it may in fact explain the absence of fossils from fish who preferred
> living in volcanic caves and overhangs in very deep ocean habitats.
> However, it seems like the theory of subduction itself is not
> completely without its flaws.
You've got to be kidding. Are you denying everything that's been done in the
last several decades of geology, as well as in the last century and a half of
evolution? On what basis? (The argument you present below is essentially an
argument from ignorance.)
> Evidence of significant subduction as a
> means for sediment removal seems to be rather lacking as far as I can
> tell. There is even argument as to what forces might be stable enough
> to drive such prolonged subduction of huge portions of the earth's
> crust over the course of hundreds of millions of years.
Who is making these arguments?
> In any case,
> there have been recent finds of coelacanths off the coast of the
> Comoro Islands in 1998 that do not live in very deep water (~200m) or
> in caves. How did these coelacanths survive without being fossilized
> over the course of 80 million years?
How do you know they weren't fossilized? Have studies been done searching for
fossils on the ocean floor? If you know of any such, please enlighten us.
> > > Interesting argument I think.
>
> -
>
> > It is interesting. I would be very interested in why Mr.
> > Pitman expects paleontologists to be able to find fossils
> > in sediments that are either underwater and buried
> > beneath younger sediments or consist of badly deformed
> > even metamorphosed sediments. If this argument is invalid,
> > Mr. Pitman should have absolutely no trouble at all
> > pointing specific outcrops of sedimentary strata where
> > a person could look for the remains of coelacanths.
>
> -
>
> The vast majority of sedimentary layers in the geologic column were
> formed underwater. I am rather surprised that anyone would argue this
> point. For example, it is thought that all of the layers in the Grand
> Canyon, save the Coconino Sandstone layer, was formed underwater.
> Yet, there it is for all to see, above water. The coelacanths that
> are fossilized, also lived underwater once upon a time. The argument
> here is that their habitat was more conducive to fossilization than
> the habitat of the modern coelacanths. Conduciveness is a bit
> different from preservation potential however. Subduction arguments
> do not argue so much against conduciveness, but against preservation
> potential. However, we do have supposedly ancient deep sea sediments
> preserved in the fossil record. Somehow they managed to survive
> destruction by subduction.
"Somehow"? Do you think there's a mystery here? Not all deep-sea regions are
near subduction zones; this was just as true in the past as it is in the
present. Also, even though these areas may have been underwater at one time,
they *were* still over continental crust, which for the most part is never
subducted (because it's lighter and less dense).
> In any case, more populations of
> coelacanths have been found that live in shallower waters that are not
> protected by deep sea caves. Yet, these fishes somehow avoided
> fossilization as well. This seems rather strange to me. Of course,
> coelacanths are not the only ones to seemingly be raised up after tens
> of millions of years of extinction. There are a large number of other
> fossils to include entire orders of creatures that disappear from tens
> of millions of years, and then reappear suddenly in the fossil record.
> These examples are so common that they have been given the name,
> "Lazarus Taxa."
I don't doubt this, because the geologic record is largely incomplete. This is
not explicable if the geologic record resulted from a global flood dumping huge
volumes of sediment - in that case we should expect massive, thorough
preservation throughout all strata, and *no* strata anywhere (such as the Grand
Canyon Coconino Sandstone, which you alluded to above) which are aeolian,
volcanic (other than pillow lava) or any other type which could not form
underwater.
> > > Fossilization requires rapid burial or else decay will
> > > obliterate all traces.
>
>
> > This is not completely true. Bones can survive for over
> > a year before being buried.
>
> This depends upon the environment in which they are deposited as well
> as the size of the bones. Also, well preserved fossils of completely
> intact specimens, to include soft tissue impressions in fine detail,
> as is the case with many of the coelacanth fossils, requires rapid
> burial.
I strongly doubt that. Fossils deposited in anoxic lakes, for example, often
preserve soft tissue information without requiring rapid burial, as decay
doesn't occur down there. (IIRC, these are the conditions thought to have
existed during the time the Yixian Formation in China, which has given us so
many excellently preserved examples of feathered theropods, was formed.)
[snip]
> > If Mr. Pitman would research the fossilziation of fish,
> > he would find the statement "practically all fossils of
> > fish show evidence of catastrophic burial" to be a rather
> > gross exaggeration of what the facts show. For example,
> > the research by Maisey (1991) of the origins of the
> > Santana fossil fish clearly demonstrates the lack of
> > catastophe in their formation. Rather, they represent
> > fish that died and sank to the bottom of a large anoxic
> > lake over a period of thousands of years. The decay of
> > the fish on the bottom precipitated carbonate minerals
> > that preserved them as fossils.
>
> In modern times, how often do you see this picture proposed by Maisey
> happening? Fish simply do not fossilize in modern "anoxic lakes" like
> they did in the past.
Explain this statement, please?
> Some pictures of the Santana Fossils can be
> seen at:
>
> http://www.uoguelph.ca/zoology/rush/zoo402www/ichthyology7.html
>
> They are surprisingly well preserved. They show excellent scale, fin,
> and eye socket preservation. This seems rather strange to me because
> many fish float when they die and rapidly decompose, even while
> sinking.
They float *because* they begin to decompose and fill up with gas. Decomposition
does not occur in anoxic waters, which is why they're so good at preservation.
[snip]
> > Finally, these fossils only demonstrate
> > how some Young Earth creationists are incapable of
> > recognizing a fish that choked on trying to eat a fish
> > far larger than it could swallow.
>
>
> Really? The fish choked to death? Then both of the fishes drifted
> down to the bottom of the lake and were perfectly preserved somehow
> without any significant evidence of decay or predation? Come on now.
> How often do you see fish choking on other fish today? Have you ever
> seen a fish choking on another fish that it is trying to eat? But
> hey, lets just say that it can happen. A fish can have eyes bigger
> than its mouth. It tries to eat something that is just too big to
> handle. Its meal gets stuck and its gills get blocked, and so it
> suffocates to death. However rare this event might be, how rare would
> it be for these two struggling fish avoid being eaten by some other
> predator or scavenger before they became buried in the scavenger rich
> mud at the bottom? Really, how rare would this be? I doubt it would
> ever happen once in ten million years without some sort of rapid
> burial event occurring at exactly the same time.
But the geologic record, of course, is far longer than ten million years, and so
contains more opportunities for such a rare event to occur.
[snip]
> > How does hydraulic sorting explain
> > the biostratigraphy of microfossils?
>
> Hydraulic sorting doesn't explain the biostratigraphy of microfossils.
> There are other ways that sorting can happen you know. The natural
> habitat itself acts as a sorter.
Elaborate, please.
> Also, the same species can have a
> different look in different environments. Phenotypic variation does
> not always depend upon genotypic change, but can often change in tune
> with changing environmental needs. Such changes that are based in
> environmental changes are called, "ecophenotypic variations."
> Microfossils, such as foraminifers, demonstrate a wide variety of
> ecophenotypes. In fact, many phenotypes that were once thought to
> represent different species groups are now known to represent
> difference phenotypic variations within the same species.
That still doesn't explain their vertical sorting, which was his point.
> > What I would like Young Earth creationists to explain is
> > why microfossils which lived in the same ocean are so
> > nicely stratified according to age. First go read
> > "Microfossil Stratigraphy Presents Problems for the
> > Flood" by Glenn R. Morton at:
> >
> > http://www.glenn.morton.btinternet.co.uk/micro.htm
> >
> > He gives a few of innumerable examples where foraminifera
> > and other microsfossils are found in the same stratigraphic
> > sequence over large areas, even world-wide. A person cannot
> > explain this in terms of either location or habitat zonation.
>
> Actually, a person can explain this in terms of both location as well
> as habitat zonation.
I fail to see how. Whatever zonation conditions existed before the flood would
be pretty thoroughly destroyed once the violent turbulence of the waters began.
(This is a remarkable flood you believe in. On the one hand it can be violent
and catastrophic enough to produce vast formations such as the Grand Canyon,
whereas on the other it can be so slow and gentle that it buries successive
foraminifera layers without so much as disturbing their relative sorting.)
[snip]
I think your case in general is weak. I don't doubt that the geologic record
contains numerous instances of local catastrophes, but for you to attempt to
yoke these together into one global catastrophe cannot be sustained. The
geologic record contains aeolian (wind-blown) layers that cannot be deposited
underwater. It contains igneous strata other than pillow lava, none of which can
occur underwater. It has layers that preserve fine details such as footprints
and handprints, mud cracks, animal burrows, delicate nests, raindrop imprints,
none of which could be preserved during a catastrophic flood. It contains layers
that were tilted, folded and eroded before the next layer was laid down -
impossible during a flood. It contains numerous fine-grained layers of laminated
sediment which would have to form with impossible speed and precision during a
flood. The global flood was a primitive 19th-century notion that was only
sustainable when geology as we know it was a science in its infancy. The
creationists' attempts to resurrect it speak only of their superstitious bias
against the truth and cannot possibly be borne out by any rational consideration
of the actual evidence.
--
And I want to conquer the world,
give all the idiots a brand new religion,
put an end to poverty, uncleanliness and toil,
promote equality in all of my decisions...
--Bad Religion, "I Want to Conquer the World"
http://www.ebonmusings.org ICQ: 8777843 PGP Key ID: 0x5C66F737
Sean Pitman M.D.
> I have personally seen and felt the overwhelming evidence for the
> theory of subduction. In the Pacific Northwest, we have a volcanic
> mountain range (the Cascade Mountains) running parallel to an ocean
> trench about 50-miles distant, as is found in other parts of the
> world. We find evidence of earlier, extinct volcanic ranges parallel
> to evidence of older ocean shores. We find partially metamorphosed
> ocean sediment in the Cascades. We have earthquakes. We have uplifted
> ocean floor along the coast, where we can see pillow basalts that
> formed underwater. We have trench filling thrust up to form the
> Olympic Mountain range. Your suggestion that the theory of subduction
> is flawed is simply laughable.
"Simply Laughable"? Perhaps, but I am not the only one who thinks
that there are some problems with the theory. Don't get me wrong, I
do think that some subduction has taken place. I just don't know
about the degree or timing of this subduction. One problem is the
mechanism for moving continents around. There seems to be some
argument on just how this is done over a prolonged period of time,
such as 200 million years or so (Kundt and Jessner 1986, Loper
1985, Lowman 1985a, Pavoni 1986, Runcorn 1980, Walzer and Maaz 1983).
Some evidence also suggests that some of the continents have very deep
"roots" with depths of over 700km (Kerr 1986, Lay 1988, Lowman 1985a).
Explanations seem lacking how just how such massive and deeply rooted
plates can be floated around and pushed under one another so easily
and steadily over a very prolonged course of time. Just last month I
saw a PBS television program dealing with plate tectonics. Some
geologists interviewed on this program argued that the proposed
"convection currents" just are not powerful enough to force oceanic
plate subduction. The movement of plates with such deep roots seems
so incredible that a fixed-earth plate-tectonic model has been
proposed that requires subduction zones which have not been suspected
before and for which there is little evidence (Lowman 1985b, Lowman
1986, Martin 1987, Schmidt and Embleton 1986). Another difficulty is
that both the African and the Antarctic tectonic plates are almost
completely surrounded by spreading ridges with no significant
subduction zones on their boundaries (Bevis and Payne 1983; Karig
1978). Consequently, the subduction zones available to accommodate the
spreading are not near by; and these expansion ridges themselves would
have to migrate toward distant subduction zones. In fact, models of
relative plate motions have not been unambiguously established yet,
particularly for the circum-Pacific (Kamp and Fitzgerald 1987).
These problems have led some to question the very concept of
subduction. Some argue that the slabs that are supposedly being
thrust under continental plates show caracteristics of tension rather
than compression and that there is little evidence of sediment
accretion in subduction trenches (Carey 1988, ch. 13). Some even go so
far as to argue in favor of "eduction" instead of "subduction" of
mantle material at the edges of continental shelfs (Chudinov 1981).
To explain some of these problems and yet maintain the theory of
subduction, some have proposed that the slabs sink at their edges
under their own weight more than they are being "pushed" under other
plates by the forces of expanding central ridges (Jurdy 1987,
Sekiguchi 1985, Spence 1986, Spence 1987). In this way, the tensional
characteristics frequently found in subduction zones might be
explained. Of course, this assumes that the oceanic plates were less
dense than the mantle when they were first formed at the ridges and
that they have cooled to a point of becoming more dense than the
mantle so that they sink back into it (Grow and Bowin 1975, Kerr 1988,
Park 1988). Obviously though, the ridges themselves are "cooler" than
the mantle. So, what does cooling have to do with anything? Also,
the question remains as to why an oceanic slab should descend under a
continental shelf (Mueller and Panza 1986). Others agree that
subduction models are difficult to support because subduction destroys
most of its evidence; so "little is yet known about its
mechanics"(Anderson 1981, Rea and Duncan 1986). Additional problems
have been raised by Uyeda(1986). Subduction is a complex process
involving an interplay of various forces that are difficult to
quantify (Jarrard 1986).
At least by the early to late 1980s, no agreement had been reached as
to an accepted model of subduction. Note the conclusion of the 1982
U.S. Geodynamics committee workshop: "No generally accepted models
exist for the initiation of [subduction]", "rates and mechanisms of
assimilation of models for the heating of subducted slabs [are] wholly
inadequate", and "gravity profiles across subduction zones and the
published geoid data do not reflect the thermally predicted excess
mass" (Lithosphere 1983, pp. 28, 29).
Then, there are the controversial theories of the Australian geologist
S. Warren Carey, which I do not necessarily agree with and which I
believe have been generally discredited, but it is interesting how he
came to propose his "expanding earth" model (The Expanding Earth,
1976. S. Warren Carey. Elsevier Scientific Publishing Company,
Amsterdam, The Netherlands. 488 pp.) He states, "Subduction exists
only in the minds of its creators" (p. 16) and "the Pacific subduction
zones like all other subduction zones are myths" (p. 50). This is the
crucial difference between standard plate tectonic theory and Carey's
expansion model, for both schools of thought agree on sea-floor
spreading but differ on the interpretation of the trenches (p. 54).
Arguments that he uses to support these contentions are:
a.Lack of off-scraping of trench deposits (pp. 56, 59-60).
b.Thinning and necking of earth's crust in area of trenches
and other topographic evidence that indicates the trenches
are tensional rifts, not compressional features (pp. 28, 52,
59, 63-65).
c.Increase in heat flux at trenches and orogenic belts which
is not consistent with subduction (pp. 58, 69).
d.No indication from seismic data that the Moho bends down at the
trenches(p. 62).
e.Magnetic anomalies get older away from the Aleutian trench as
though it were a spreading zone (p. 59).
Carey also cites studies which claim that seismic (p. 74) and
paleomagnetic data (p. 195) have been screened and selectively
interpreted to be consistent with assumed subductions.
Perhaps these questions have been completely resolved over the past
10-20 years? If so, I have yet to see that there is general agreement
about subduction theory. Maybe those in this forum can enlighten me
as to the general agreement as to the processes of subduction theory.
Sean
References:
Kundt, W. and A. Jessner. 1986. Volcanoes, fountains, earthquakes, and
continental motion — what causes them? Journal of Geology 60:33-40.
Loper, D. E. 1985. A simple model of whole-mantle convection. Journal
of Geophysical Research 90(B2):1809-1836.
Lowman, P. D., Jr. 1985. Mechanical obstacles to the movement of
continent-bearing plates. Geophysical Research Letters 12:223-225.
Lowman, P. D., Jr. 1985b. Plate tectonics with fixed continents: a
testable hypothesis-I. Journal of Petroleum Geology 8:373-388.
Lowman, P. D., Jr. 1986. Plate tectonics with fixed continents: a
testable hypothesis-II. Journal of Petroleum Geology 9:71-88.
Pavoni, N. 1986. Regularities in the pattern of major fault zones of
the earth and the origin of arcs. In Wezel 1986a, pp. 63-78.
Runcorn, S. K. 1980. Mechanism of plate tectonics: mantle convection
currents, plumes, gravity sliding or expansion? Tectonophysics
63:297-307.
Walzer, U. and R. Maaz. 1983. On intermittent lower-mantle convection.
In Carey 1983a, pp. 329-340.
Kerr, R. A. 1986. The continental plates are getting thicker. Science
232:933-934.
Kerr, R. A. 1988. The mantle's structure — having it both ways.
Science 240:1735.
Lay, T. 1988. The deep roots of continents. Nature 333:209-210.
Martin, B. D. 1987. Comments on "Plate-tectonics with fixed
continents: a testable hypothesis-I and II". Journal of Petroleum
Geology 10:351-352.
Schmidt, P. W. and B. J. J. Embleton. 1986. Comments on "Plate
tectonics with fixed continents: a testable hypothesis-II" by P. D.
Lowman, Jr. Journal of Petroleum Geology 9:349-351.
Bevis, M. and B. Payne. 1983. A new Palaeozoic reconstruction of
Antarctica, Australia and South America. In Carey 1983a, pp. 207-213.
Karig, D. E. 1978. The expanding Earth (A Review of Carey, 1976).
Journal of Geology 86:280-281.
Kamp, P. J. J. and P. G. Fitzgerald. 1987 Geologic constraints on the
Cenozoic Antarctica-Australia-Pacific relative plate motion
circuit.Geology 15:694-697.
Carey, S. W. 1988. Theories of the Earth and universe. Stanford
University Press, Stanford, California.
Chudinov, Yu. V. 1981. The expanding Earth and tectonic movements:
direction of movements in marginal oceanic zones. Geotectonics
15:11-22.
Jurdy, D. M. 1987. Plates and their motions. Reviews of Geophysics
25:1286-1292.
Sekiguchi, S. 1985. The magnitude of driving forces of plate motion.
Journal of Physics of the Earth 33:369-389.
Spence, W. 1986. The 1977 Sumba Earthquake series: evidence for slab
pull force acting at a subduction zone. Journal of Geophysical
Research 91(B7):7225-7239.
Spence, W. 1987. Slab pull and the seismotectonics of subducting
lithosphere. Reviews of Geophysics 25:55-69.
Grow, J. A. and C. O. Bowin. 1975. Evidence for high-density crust and
mantle beneath the Chile Trench due to the descending lithosphere.
Journal of Geophysical Research 80:1449-1458.
Park, R. G. 1988. Geological structures and moving plates. Blackie &
Son, Ltd., Glasgow, Scotland and London.
Mueller, S. and G. F. Panza. 1986. Evidence of a deep-reaching
lithospheric root under the Alpine arc. In Wezel 1986a, pp. 93-113.
Anderson, R. N. 1981. Surprises from the Glomar Challenger. Nature
293:261-262.
Rea, D. K. and R. A. Duncan. 1986. North Pacific Plate convergence: a
quantitative record of the past 140 m.y. Geology 14:373-376.
Uyedu, S. 1986. Facts, ideas and open problems on trench-arc-backarc
systems. In Wezel 1986a, pp. 435-460.
Jarrard, R. D. 1986. Relations among subduction parameters. Reviews of
Geophysics 24:217-284.
Lithosphere. 1983. The lithosphere: report of a workshop. National
Academy Press, Washington, D.C.
John Harshman
Sean...@juno.com (Sean Pitman M.D.) wrote:
Aside from problems such as ignoring the differences between oceanic and
continental crust, is there a particular reason why your most recent
references for this little piece are 14 years old, and references
average several years older? Have there been no advances our
understanding of plate tectonics in all that time?
Where did you get this? The age of the references would suggest that you
found it intact somewhere instead of coming up with it yourself. It's
considered good form to cite your real source, in addition to the
sources used by the source.
This is also an excellent example of your favorite tactic: if we don't
know everything, then we must know nothing. Surely we know enough to see
that oceanic crust is arise at mid-ocean ridges and disappearing (by
some means or other) at trenches. Otherwise the age-distribution of
oceanic crust can't be explained.
By the way, if you really want answers to all this, wouldn't it be wise
to post to a sci.geology group?
Note this little switch. You go right from talking about the roots of
continents (alleged to be as much as 700km deep) to "pushed under one
another", e.g. subduction, which of course only happens to oceanic
crust, ignoring the difference.
> Just last month I
> saw a PBS television program dealing with plate tectonics. Some
> geologists interviewed on this program argued that the proposed
> "convection currents" just are not powerful enough to force oceanic
> plate subduction.
But we can understand the phenomenon well enough to know that it happens
without being able to demonstrate its mechanism, can't we?
> The movement of plates with such deep roots seems
> so incredible that a fixed-earth plate-tectonic model has been
> proposed that requires subduction zones which have not been suspected
> before and for which there is little evidence (Lowman 1985b, Lowman
> 1986, Martin 1987, Schmidt and Embleton 1986).
Sounds weird to me. And how do you account for measured motions of the
continents (by laser) over the last several years?
Let's use correct terminology here. Lithospheric plates are composed of
crust *and* mantle material. The crust material (on top) will be less
dense than the mantle at any temperature. The mantle material (on the
bottom) will be the same density as other mantle material at the same
temperature. Of course as it cools it may become denser than the
underlying parts of the mantle.
> Obviously though, the ridges themselves are "cooler" than
> the mantle.
Obviously? What part of the ridges? Not the part that consists of magma,
certainly. You mean the solid parts. Sure. But the crust away from the
surface, at the ridges, is hotter than the older crust far from the
ridge (and possibly hotter than some parts of the mantle). Consider two
objects of identical size and shape, one of them 3/4 g/cc and one of
them 1/2 g/cc. Both will float in water, but the top of the denser one
is still much lower than the top of the lighter one. Right? It's easier
to subduct a denser rock than a lighter rock.
> So, what does cooling have to do with anything?
You assume both homogeneity of plates with depth (false) and that there
are only two relevant degrees of density: less than mantle and greater
than mantle (false).
> Also,
> the question remains as to why an oceanic slab should descend under a
> continental shelf (Mueller and Panza 1986). Others agree that
> subduction models are difficult to support because subduction destroys
> most of its evidence; so "little is yet known about its
> mechanics"(Anderson 1981, Rea and Duncan 1986). Additional problems
> have been raised by Uyeda(1986). Subduction is a complex process
> involving an interplay of various forces that are difficult to
> quantify (Jarrard 1986).
>
> At least by the early to late 1980s, no agreement had been reached as
> to an accepted model of subduction. Note the conclusion of the 1982
> U.S. Geodynamics committee workshop: "No generally accepted models
> exist for the initiation of [subduction]", "rates and mechanisms of
> assimilation of models for the heating of subducted slabs [are] wholly
> inadequate", and "gravity profiles across subduction zones and the
> published geoid data do not reflect the thermally predicted excess
> mass" (Lithosphere 1983, pp. 28, 29).
>
> Then, there are the controversial theories of the Australian geologist
> S. Warren Carey, which I do not necessarily agree with and which I
> believe have been generally discredited,
Stop right there. Why are you bringing up a discredited theory? What
does it do except muddy the issue?
I'm not a geologist. I know enough to doubt much of your understanding
here, but not to answer all your questions. But this hardly seems like
an attempt to shed light on anything. All you are doing is implying that
any theory that doesn't explain everything, right now (or right 14 years
ago, actually) must be worthless. Does that make any sense?
>
Inconsistencies in your citations (below) lead me to wonder whether you
have read any of these yourself. Have you? At the very least,
alphabetical sorting by author is customary and would have been only
polite.
Is this a valid reference? Context would suggest that this is an edited
volume, and Carey merely the editor. If he has his own chapter (and you
attribute views to him above) then that should be cited separately.
Wezel? Where's Wezel? There's no Wezel at all, much less multiple
citations from 1986. Very suspicious.
> Jarrard, R. D. 1986. Relations among subduction parameters. Reviews of
> Geophysics 24:217-284.
>
> Lithosphere. 1983. The lithosphere: report of a workshop. National
> Academy Press, Washington, D.C.
>
--
*Note the obvious spam-defeating modification
to my address if you reply by email.
Ron Okimoto
"Sean Pitman M.D." wrote:
> > R. Baldwin
>
> > I have personally seen and felt the overwhelming evidence for the
> > theory of subduction. In the Pacific Northwest, we have a volcanic
> > mountain range (the Cascade Mountains) running parallel to an ocean
> > trench about 50-miles distant, as is found in other parts of the
> > world. We find evidence of earlier, extinct volcanic ranges parallel
> > to evidence of older ocean shores. We find partially metamorphosed
> > ocean sediment in the Cascades. We have earthquakes. We have uplifted
> > ocean floor along the coast, where we can see pillow basalts that
> > formed underwater. We have trench filling thrust up to form the
> > Olympic Mountain range. Your suggestion that the theory of subduction
> > is flawed is simply laughable.
>
> "Simply Laughable"? Perhaps, but I am not the only one who thinks
> that there are some problems with the theory. Don't get me wrong, I
> do think that some subduction has taken place. I just don't know
> about the degree or timing of this subduction. One problem is the
> mechanism for moving continents around. There seems to be some
> argument on just how this is done over a prolonged period of time,
> such as 200 million years or so (Kundt and Jessner 1986, Loper
> 1985, Lowman 1985a, Pavoni 1986, Runcorn 1980, Walzer and Maaz 1983).
> Some evidence also suggests that some of the continents have very deep
> "roots" with depths of over 700km (Kerr 1986, Lay 1988, Lowman 1985a).
Snip:
Not that I don't think that you have read all these papers, but they
suspiciously all end in the 1980's. Where are the references from the
1990's and the last three years? Remember the honest thing to do is to
cite your actual source. If it is a creationist source we know that it is
90% bull and we can ignore your quotes. You know this too, or you would
do the honest thing. Remember that reference to a slug? You keep denying
that you act like one.
How do all these quotes help your idea of how the plates move. Remember
the YEC guys think that the plates all moved to their present positions in
just one or a few years. Doesn't look like that is possible for deep
rooted plates, does it?
Ron Okimoto
>
> Sean
>
> References:
KelvynT
>In article <fd67d42a.02112...@posting.google.com>,
> Sean...@juno.com (Sean Pitman M.D.) wrote:
>
>Aside from problems such as ignoring the differences between oceanic and
>continental crust, is there a particular reason why your most recent
>references for this little piece are 14 years old, and references
>average several years older? Have there been no advances our
>understanding of plate tectonics in all that time?
>
>Where did you get this? The age of the references would suggest that you
>found it intact somewhere instead of coming up with it yourself. It's
>considered good form to cite your real source, in addition to the
>sources used by the source.
<big snip>
Well, here's a good sized chunk of it. Fom a 1988 article by a certain
Prof. Bill Mundy, who doesn't seem make it into Sean's bibliography.
http://www.grisda.org/origins/15053.htm
Kelvyn
Robin Levett
Sean, can we agree that you have lifted much of this from:-
http://www.grisda.org/origins/15053.htm
Can we also agree that you have not credited that site with having
done so?
Have you complained about being described as possessing the
integrity of a slug?
<snip references>
--
The end of the world is off topic in sci.geo.satellite-nav and
probably
also on sci.astro.amateur - "Graham" (crossposted also to
sci.geo.geology)
John Harshman
KelvynT <removethi...@ntlworld.com> wrote:
Yes, that looks like a good part of it, if not all. I note that this is
a creationist source, and that the other article on that site looks like
it may be a source for some of Dr. Sean's other geological
pronouncements too. Another case of creationist recycling. I think Dr.
Sean has managed to garble a couple of Mundy's attempted points as well.
Jon Fleming
>> Uyedu, S. 1986. Facts, ideas and open problems on trench-arc-backarc
>> systems. In Wezel 1986a, pp. 435-460.
>
>Wezel? Where's Wezel? There's no Wezel at all, much less multiple
>citations from 1986. Very suspicious.
Could well be a cut-and-paste job ...
Noelie S. Alito
news:harshman.diespamdie-...@news.infinet.mindspring.com...
> In article <fd67d42a.02112...@posting.google.com>,
> Sean...@juno.com (Sean Pitman M.D.) wrote:
>
> Aside from problems such as ignoring the differences between oceanic and
> continental crust, is there a particular reason why your most recent
> references for this little piece are 14 years old, and references
> average several years older? Have there been no advances our
> understanding of plate tectonics in all that time?
>
> Where did you get this? The age of the references would suggest that you
> found it intact somewhere instead of coming up with it yourself. It's
> considered good form to cite your real source, in addition to the
> sources used by the source.
>
> This is also an excellent example of your favorite tactic: if we don't
> know everything, then we must know nothing. Surely we know enough to see
> that oceanic crust is arise at mid-ocean ridges and disappearing (by
> some means or other) at trenches. Otherwise the age-distribution of
> oceanic crust can't be explained.
>
> By the way, if you really want answers to all this, wouldn't it be wise
> to post to a sci.geology group?
Would they waste their time on this Knowlege of the Ancients?
Yikes! I missed that. As far as we've just been taught in our
undergraduate class, the current deepest "continental root" is
under the Himalayas, around 70 (seventy) km, though there is
evidence of some past crustal rock reaching down as far as 100km.
The deepest recorded earthquakes for subducting plates, IIRC,
are on the order of 700 (seven hundred) km.
<http://earthquake.usgs.gov/image_glossary/benioff.html>
> > Just last month I
> > saw a PBS television program dealing with plate tectonics. Some
> > geologists interviewed on this program argued that the proposed
> > "convection currents" just are not powerful enough to force oceanic
> > plate subduction.
>
> But we can understand the phenomenon well enough to know that it happens
> without being able to demonstrate its mechanism, can't we?
There are several competing explanations for the driving mechanism
behind various aspects of plate tectonics. AIUI, the leading
contenders are that the plates are [also] *pulled*, either by the
mantle heat/depth/density dynamics or positive feedback due to
what happens to plate material where it's pulled under the [volcano]
zone of the continent. The relatively thin ocean plates aren't
considered structurally strong enough for the original pushing-alone
mechanism.
> > The movement of plates with such deep roots seems
> > so incredible that a fixed-earth plate-tectonic model has been
> > proposed that requires subduction zones which have not been suspected
> > before and for which there is little evidence (Lowman 1985b, Lowman
> > 1986, Martin 1987, Schmidt and Embleton 1986).
>
> Sounds weird to me. And how do you account for measured motions of the
> continents (by laser) over the last several years?
I still don't understand that "700 km" number, but such a keel could,
depending on the dynamics at different depths of the mantle, either
hold continents in place (leaving the bulk of the relative movement
to ocean plates), or conversely increase the lateral movement of
that continent. Either way, as long as the many ocean plates are
not tied down, there is plenty of room for crustal movement. (And
somebody should tell the Indian plate that it is not supposed to be
ramming into the Asian plate.)
> > Another difficulty is
> > that both the African and the Antarctic tectonic plates are almost
> > completely surrounded by spreading ridges with no significant
> > subduction zones on their boundaries (Bevis and Payne 1983; Karig
> > 1978). Consequently, the subduction zones available to accommodate the
> > spreading are not near by; and these expansion ridges themselves would
> > have to migrate toward distant subduction zones. In fact, models of
> > relative plate motions have not been unambiguously established yet,
> > particularly for the circum-Pacific (Kamp and Fitzgerald 1987).
The plate motions are *measured* and *known*. Many aspects of
various driving models have been tested since 1987, so they've been
able to throw out some of the first ones proposed. Furthermore
cheap computrons and more extensive measurement technology
have enabled geophysicists to test and extend knowlege of the
mantle dynamic. Although we are dealing with well-understood
physical properties (heat, density, inertia, and so forth), having
the means of modeling how plates on a spheroid move relative
to one another is a fairly recent technological accomplishment.
> > These problems have led some to question the very concept of
> > subduction. Some argue that the slabs that are supposedly being
> > thrust under continental plates show caracteristics of tension rather
> > than compression and that there is little evidence of sediment
> > accretion in subduction trenches (Carey 1988, ch. 13). Some even go so
> > far as to argue in favor of "eduction" instead of "subduction" of
> > mantle material at the edges of continental shelfs (Chudinov 1981).
> >
> > To explain some of these problems and yet maintain the theory of
> > subduction, some have proposed that the slabs sink at their edges
> > under their own weight more than they are being "pushed" under other
> > plates by the forces of expanding central ridges (Jurdy 1987,
> > Sekiguchi 1985, Spence 1986, Spence 1987). In this way, the tensional
> > characteristics frequently found in subduction zones might be
> > explained. Of course, this assumes that the oceanic plates were less
> > dense than the mantle when they were first formed at the ridges and
> > that they have cooled to a point of becoming more dense than the
> > mantle so that they sink back into it (Grow and Bowin 1975, Kerr 1988,
> > Park 1988).
>
> Let's use correct terminology here. Lithospheric plates are composed of
> crust *and* mantle material. The crust material (on top) will be less
> dense than the mantle at any temperature. The mantle material (on the
> bottom) will be the same density as other mantle material at the same
> temperature. Of course as it cools it may become denser than the
> underlying parts of the mantle.
Ah, beat me to it. (And the physics of rock does indicate that cool
ocean plate lithosphere material is denser than the mantle--especially
after some of the lighter topping has been taken off at the point of
subduction.)
> > Obviously though, the ridges themselves are "cooler" than
> > the mantle.
>
> Obviously? What part of the ridges? Not the part that consists of magma,
> certainly. You mean the solid parts. Sure. But the crust away from the
> surface, at the ridges, is hotter than the older crust far from the
> ridge (and possibly hotter than some parts of the mantle). Consider two
> objects of identical size and shape, one of them 3/4 g/cc and one of
> them 1/2 g/cc. Both will float in water, but the top of the denser one
> is still much lower than the top of the lighter one. Right? It's easier
> to subduct a denser rock than a lighter rock.
>
> > So, what does cooling have to do with anything?
>
> You assume both homogeneity of plates with depth (false) and that there
> are only two relevant degrees of density: less than mantle and greater
> than mantle (false).
Analysis of subduction volcanism show that a major contributor to
the melting of _crustal_ volcanic rock is the H20-rich topping to
the subducting plate. Those who refuse to do the differential
equations are condemned to talk nonsense. ;-)
> > Also,
> > the question remains as to why an oceanic slab should descend under a
> > continental shelf (Mueller and Panza 1986). Others agree that
> > subduction models are difficult to support because subduction destroys
> > most of its evidence; so "little is yet known about its
> > mechanics"(Anderson 1981, Rea and Duncan 1986). Additional problems
> > have been raised by Uyeda(1986). Subduction is a complex process
> > involving an interplay of various forces that are difficult to
> > quantify (Jarrard 1986).
> >
> > At least by the early to late 1980s, no agreement had been reached as
> > to an accepted model of subduction. Note the conclusion of the 1982
> > U.S. Geodynamics committee workshop: "No generally accepted models
> > exist for the initiation of [subduction]", "rates and mechanisms of
> > assimilation of models for the heating of subducted slabs [are] wholly
> > inadequate", and "gravity profiles across subduction zones and the
> > published geoid data do not reflect the thermally predicted excess
> > mass" (Lithosphere 1983, pp. 28, 29).
> >
> > Then, there are the controversial theories of the Australian geologist
> > S. Warren Carey, which I do not necessarily agree with and which I
> > believe have been generally discredited,
>
> Stop right there. Why are you bringing up a discredited theory? What
> does it do except muddy the issue?
<snipping 1976(?) theory>
> > Perhaps these questions have been completely resolved over the past
> > 10-20 years? If so, I have yet to see that there is general agreement
> > about subduction theory. Maybe those in this forum can enlighten me
> > as to the general agreement as to the processes of subduction theory.
The motion of the plates has been confirmed by ever-increasing number
of satellites capable of such fine measurements. The earthquake patterns,
for which we also have ever-refined detection capability, shows conforms
to the angled plate-plate contact of the subduction zone. In addition,
the combination of increased seismic sensing coverage and availabilty
of computers has shown through tomography (know how a CAT scan
is generated?) the interior earth structures of subducting plate remnants.
The motions of the plates are pretty much a given, and now the
geophysicists are duking it out over the relative contributions of
various mechanisms.
As far as continental thickness is concerned, the "Moho discontinuity"
which indicates the bases of the continents was first discovered in 1909
(over 90 years ago), and has been measured in excruciating detail by
newer technology. Those pesky satellites (and other ground-based
measures) have confirmed areas of crustal thickening as well as
isostatic rebound (how the continental crust floats higher when weight
is removed by erosion or melting). This is not a dead planet.
> I'm not a geologist. I know enough to doubt much of your understanding
> here, but not to answer all your questions. But this hardly seems like
> an attempt to shed light on anything. All you are doing is implying that
> any theory that doesn't explain everything, right now (or right 14 years
> ago, actually) must be worthless. Does that make any sense?
Perhaps this purported _pathologist_ can tell us whether diagnostic
equipment has changed at all since 1987? (I mean, they should
know about technological improvements, right?)
> Inconsistencies in your citations (below) lead me to wonder whether you
> have read any of these yourself. Have you? At the very least,
> alphabetical sorting by author is customary and would have been only
> polite.
<snipping all references but this>
> >
> > Carey, S. W. 1988. Theories of the Earth and universe. Stanford
> > University Press, Stanford, California.
>
> Is this a valid reference? Context would suggest that this is an edited
> volume, and Carey merely the editor. If he has his own chapter (and you
> attribute views to him above) then that should be cited separately.
<...>
> Wezel? Where's Wezel? There's no Wezel at all, much less multiple
> citations from 1986. Very suspicious.
He went by his maiden name.
Noelie
--
nnooee...@mmaaiill.uutteexxaass.eedduu
Noelie S. Alito
> "Sean Pitman M.D." <Sean...@juno.com> wrote in message
> news:fd67d42a.02112...@posting.google.com...
> > Sean
> >
>
> Sean, can we agree that you have lifted much of this from:-
>
> http://www.grisda.org/origins/15053.htm
>
> Can we also agree that you have not credited that site with having
> done so?
>
> Have you complained about being described as possessing the
> integrity of a slug?
>
> <snip references>
At this point, *I* will complain, on behalf of the slugs.
Bigdakine
>Message-id: <fd67d42a.02112...@posting.google.com>
>
>> R. Baldwin
>
>> I have personally seen and felt the overwhelming evidence for the
>> theory of subduction. In the Pacific Northwest, we have a volcanic
>> mountain range (the Cascade Mountains) running parallel to an ocean
>> trench about 50-miles distant, as is found in other parts of the
>> world. We find evidence of earlier, extinct volcanic ranges parallel
>> to evidence of older ocean shores. We find partially metamorphosed
>> ocean sediment in the Cascades. We have earthquakes. We have uplifted
>> ocean floor along the coast, where we can see pillow basalts that
>> formed underwater. We have trench filling thrust up to form the
>> Olympic Mountain range. Your suggestion that the theory of subduction
>> is flawed is simply laughable.
>
>"Simply Laughable"? Perhaps, but I am not the only one who thinks
>that there are some problems with the theory.
Oh no Dr. Pittman. THere are other kooks who agree with you.
You're iun *good* company.
Don't get me wrong, I
>do think that some subduction has taken place. I just don't know
>about the degree or timing of this subduction. One problem is the
>mechanism for moving continents around. There seems to be some
>argument on just how this is done over a prolonged period of time,
>such as 200 million years or so (Kundt and Jessner 1986, Loper
>1985, Lowman 1985a, Pavoni 1986, Runcorn 1980, Walzer and Maaz 1983).
>Some evidence also suggests that some of the continents have very deep
>"roots" with depths of over 700km (Kerr 1986, Lay 1988, Lowman 1985a).
> Explanations seem lacking how just how such massive and deeply rooted
>plates can be floated around and pushed under one another so easily
>and steadily over a very prolonged course of time.
ROFL.
Continents are passengers on plates. Plates are essentially the tops of
convection cells in the mantle.
Today, nobody seriously proposes *Continental Roots* down to 700km. Second
those roots are not Continental material, so the name is a misnomer.
Sean, you're the quintesential example of how a little knowledge is dangerous.
Just last month I
>saw a PBS television program dealing with plate tectonics. Some
>geologists interviewed on this program argued that the proposed
>"convection currents" just are not powerful enough to force oceanic
>plate subduction.
How old was that program? Second that makes no sense. My guess is you have no
understanding of what you heard.
Lithospheric slabs subduct because they are negatively bouyant. They sink, Mr
Pittman. It is the sinking of slab, Mr Pittman, that prinicipally drives mantle
convection.
The movement of plates with such deep roots seems
>so incredible that a fixed-earth plate-tectonic model has been
>proposed that requires subduction zones which have not been suspected
>before and for which there is little evidence (Lowman 1985b, Lowman
>1986, Martin 1987, Schmidt and Embleton 1986) Another difficulty is
>that both the African and the Antarctic tectonic plates are almost
>completely surrounded by spreading ridges with no significant
>subduction zones on their boundaries (Bevis and Payne 1983; Karig
>1978).
So what, Mr. Pittman?
Consequently, the subduction zones available to accommodate the
>spreading are not near by; and these expansion ridges themselves would
>have to migrate toward distant subduction zones.
Indeed this happens Mr. Pittman. Why in fact it is happening off the West coast
of the US, as the last remnants of the Farallon plate and a ridge are
subducting off the coasts of Oregon and Washington.
Do look at a tectonic map sometime.
It will do you a world of good.
In fact, models of
>relative plate motions have not been unambiguously established yet,
>particularly for the circum-Pacific (Kamp and Fitzgerald 1987).
Which areas of the Pacific and at what level of precision?
Certainly tectonics in PNG is complicated. You think relative motion along the
San Andreas is not well described over the past couple of million years?
>
>These problems have led some to question the very concept of
>subduction. Some argue that the slabs that are supposedly being
>thrust under continental plates show caracteristics of tension rather
>than compression and that there is little evidence of sediment
>accretion in subduction trenches (Carey 1988, ch. 13).
What Horse shit. Some trenches like the Chiliean, don't have huge pile of
sediment. OTOH, have a gander at the accretionary wedge complex off of
Barbados.
If thats little evidence, I'd like to see what a lot is.
Some even go so
>far as to argue in favor of "eduction" instead of "subduction" of
>mantle material at the edges of continental shelfs (Chudinov 1981).
Carey was champion of the Expanding Earth Hypothesis, which is refuted on
several grounds, Not the least of which is the dynamics of the Earth-Moon
system.
You should pick your allies more carefully. Carey was the Geology equivalent of
Fred Hoyle.
>
>To explain some of these problems and yet maintain the theory of
>subduction, some have proposed that the slabs sink at their edges
>under their own weight more than they are being "pushed" under other
>plates by the forces of expanding central ridges (Jurdy 1987,
>Sekiguchi 1985, Spence 1986, Spence 1987).
THis is called the *ridge push* force. It is essentially the hydraulic head
resulting from the cahnge of bathymetry. Ridges are elevated with respect to
trenches, and as the lithosphere acts a stress guide, this contribution along
with the negative bouyancy of contributes to the driving forces of mantle
convection.
In this way, the tensional
>characteristics frequently found in subduction zones might be
>explained.
What you're referring to is back-arc spreading. Trenches roll-back. That is,
the trench migrates oceanward. As it does so, it exerts a stress on the
overiding plate which in some cases pulls it apart, forming a rift in a
back-arc basin.
How one concludes the above means* no subduction*, I have no idea. But then
again, if you've uncrtically read Carey, its not surprising. For the record,
Jurdy was my first graduate advisor. None of this work has any bearing on the
whether subduction is real. It is. THis work addresses the process of
subduction, not its reality.
Of course, this assumes that the oceanic plates were less
>dense than the mantle when they were first formed at the ridges and
>that they have cooled to a point of becoming more dense than the
>mantle so that they sink back into it (Grow and Bowin 1975, Kerr 1988,
>Park 1988).
They are. They are also very thin at this point.
Obviously though, the ridges themselves are "cooler" than
>the mantle.
>So, what does cooling have to do with anything?
Well what do you think should happen Dr. Pittman? The stuff should good down,
right where it comes up?
You are just full of surprises.
The cooling increases the density and thickness of the lithosphere, and as such
increases the buoyancy of the lithosphere and significantly adds to the forces
driving convection.
> Also,
>the question remains as to why an oceanic slab should descend under a
>continental shelf (Mueller and Panza 1986).
Funny, I don't find it a remaining question.
In fact I can think good reasons where subdcution might initiate at a
continental shelf.
Others agree that
>subduction models are difficult to support because subduction destroys
>most of its evidence; so "little is yet known about its
>mechanics"(Anderson 1981, Rea and Duncan 1986). Additional problems
>have been raised by Uyeda(1986). Subduction is a complex process
>involving an interplay of various forces that are difficult to
>quantify (Jarrard 1986).
First off, in 1981, there was no seismic tomography, there was no residual
sphere analysis etc. Today, there is conclusive evidence that indeed subduction
takes place, and that in some areas slabs can be traced to depths of 1400km or
so, at which point they are approximately thermally equilibrated with the
mantle.
Why is it Mr. Pittman, that you have no references from the 90's? More willful
ignorance on your part? Or do you think geophysics research stopped circa 1986?
>
>At least by the early to late 1980s, no agreement had been reached as
>to an accepted model of subduction. Note the conclusion of the 1982
>U.S. Geodynamics committee workshop: "No generally accepted models
>exist for the initiation of [subduction]", "rates and mechanisms of
>assimilation of models for the heating of subducted slabs [are] wholly
>inadequate", and "gravity profiles across subduction zones and the
>published geoid data do not reflect the thermally predicted excess
>mass" (Lithosphere 1983, pp. 28, 29).
Thats the initiation of subduction Mr. Pittman. Not subduction. But nascent
subduction zones are known, and we have some pretty good clues as to the
mechanism.
See for example Kronke and Walker "Evidence for the Formation of a New Trench
in the Western Pacific" Eos vol 67., no 12, pgs 145-146, 1986
>
>Then, there are the controversial theories of the Australian geologist
>S. Warren Carey, which I do not necessarily agree with and which I
>believe have been generally discredited,
*quite*
but it is interesting how he
>came to propose his "expanding earth" model (The Expanding Earth,
>1976. S. Warren Carey. Elsevier Scientific Publishing Company,
>Amsterdam, The Netherlands. 488 pp.) He states, "Subduction exists
>only in the minds of its creators" (p. 16) and "the Pacific subduction
>zones like all other subduction zones are myths"
<Gibberish snipped>
The convergence of Pacific subduction zones is well establish by satellite
geodesy. Which didn't exist in 1981.
Only self deluded morons unable to cope with reality believe otherwise. Any
idiot who can perform a search with google on Plate Tectonics GPS can see this
for themselves.
The simple fact is Mr. Pittman. you have not searched the literature yourself.
And you certianly haven't burdened yourself with anything current.
Stuart
Dr. Stuart A. Weinstein
Ewa Beach Institute of Tectonics
"To err is human, but to really foul things up
requires a creationist"
Harlequin
m:
> In article <bbv7uugs5f03injvu...@4ax.com>,
> KelvynT <removethi...@ntlworld.com> wrote:
>
>> On Tue, 26 Nov 2002 21:01:30 +0000 (UTC), John Harshman wrote:
>>
[Snip: John Harshman notices just how ancient Dr. Pitman's
references are.]
>> Well, here's a good sized chunk of it. Fom a 1988 article by a
>> certain Prof. Bill Mundy, who doesn't seem make it into Sean's
>> bibliography. http://www.grisda.org/origins/15053.htm
>
> Yes, that looks like a good part of it, if not all. I note that this
> is a creationist source, and that the other article on that site looks
> like it may be a source for some of Dr. Sean's other geological
> pronouncements too. Another case of creationist recycling. I think Dr.
> Sean has managed to garble a couple of Mundy's attempted points as
> well.
As self-declared (as of two minutes ago) and utterly unqualified academic
dean of the University of Ediacara, I hereby assign Sean Pitman an
F for the course and place him an academic probation. Any further
plagiarism or any other academic violations of Exodus 20:15 will
result in him being expelled and all earned credits being revoked.
--
Anti-spam: replace "usenet" with "harlequin2"
Vote for The Talk.Origins Archive at
http://www.coolsiteoftheday.com/csotm.html
June
> >Subject: Re: Fish Fossils - Reply to Keith Littleton's POTM
> >From: Sean...@juno.com (Sean Pitman M.D.)
> >Date: 11/26/02 9:03 AM Hawaiian Standard Time
> >Message-id: <fd67d42a.02112...@posting.google.com>
> >
> >> R. Baldwin
> >
[snip Sean's disinformation, obfuscations, and outdated information]
>
>
> First off, in 1981, there was no seismic tomography, there was no residual
> sphere analysis etc. Today, there is conclusive evidence that indeed
> subduction takes place, and that in some areas slabs can be traced to
> depths of 1400km or so, at which point they are approximately thermally
> equilibrated with the mantle.
>
> Why is it Mr. Pittman, that you have no references from the 90's? More
> willful ignorance on your part? Or do you think geophysics research
> stopped circa 1986?
Just some interesting data/pictures, some gathered since the 1980s (I
believe).
I really like this page because it has satellite images of features that
are evidence of plate tectonics.
http://www.seismo.unr.edu/ftp/pub/louie/class/100/plate-tectonics.html
This is just one page from an excellent USGS site re introduction to
plate tectonics.
http://pubs.usgs.gov/publications/text/understanding.html
The Hawaiian hot spot and the sea mount/island chain that is some of the
evidence for movement of the Pacific plate.
http://pubs.usgs.gov/publications/text/Hawaiian.html
Great site with satellite laser ranging (SLR) graphic data showing
worldwide continental movements.
http://cddisa.gsfc.nasa.gov/926/slrtecto.html
Even if we had no clue as to the mechanisms, the evidence for the
existence and movement of plates on the Earth's outer layer is pretty
overwhelming. Features like the Hawaiian Island chain are compelling
evidence of these movements continuing for many millions of years.
Here's just an example.
http://sideshow.jpl.nasa.gov/mbh/series.html
>
> The simple fact is Mr. Pittman. you have not searched the literature yourself.
> And you certianly haven't burdened yourself with anything current.
Obviously.
>
> Stuart
>
>
> Dr. Stuart A. Weinstein
> Ewa Beach Institute of Tectonics
> "To err is human, but to really foul things up
> requires a creationist"
--
My 2¢ B-}
June
Sean Pitman M.D.
<snip>
> Not that I don't think that you have read all these papers, but they
> suspiciously all end in the 1980's.
Obviously I haven't read all of these papers nor did I wish to
indicate that I had. This area is not (obviously) my area of training
or special interest, although I do find it interesting. It was
nothing more than a side point to my reply to Keith Littleton's post.
And yet, this small side comment seems to have drawn a lot of
attention. My main contention here is not to say that subduction does
not happen. I think that subduction does happen and has happened. My
question concerns the driving force behind subduction and if such
forces might have acted at different rates, even dramatically
different rates, in the past. Previously I had read a couple of papers
dealing with this issue and used information from these. In fact, my
main questions (with the references used here) come from a paper that
can be found at:
http://www.grisda.org/origins/15053.htm
> Where are the references from the
> 1990's and the last three years?
I figure you could point me to some good ones that are more recent. I
haven't had the chance yet to look into something more recent as of
yet. Perhaps all of the answers to the process of subduction have
been answered in the last 15 years?
> Remember the honest thing to do is to
> cite your actual source.
Oh please. This is not a review for publication here. This is a
discussion forum. It's obvious that I took the information from
another source. I didn't even TRY to hide it. It is actually very
easy to find the source that I took the information from if one so
chooses. Do you think I thought that you guys wouldn't figure this
out? Not a chance! I knew that you would know that this was
secondary source material. It is blatantly obvious. I also knew that
someone would go and look up the original source since I practically
quoted it verbatim. The source in this case happens to be a YEC
source, and actually pretty reliable as far as YEC sources go. I
wanted feedback on their information without a knee jerk response that
was based only on the fact that they are YECs. This anti-YEC bias
seems to distract from the actual issues at hand. I have also often
quoted evolutionary sources in this forum, such as talk.origins, for
the same purpose. There is a lot of yelling about YEC sources, without
really answering the actual questions that I am interested in. That
is why I presented these questions in this way. Of course many of
those in this forum spend more time yelling about sources than
discussing the issues raised. Also, many in this forum quote secondary
sources all the time without referring to the secondary source (such
as talk.origins itself). That's fine with me since I am more
interested in the ideas than I am concerned with where the ideas came
from. Of course, there are times when one needs to have actually read
all the original source material in question. In those cases, I have
indicated those original papers that I have personally read.
> If it is a creationist source we know that it is
> 90% bull and we can ignore your quotes.
That's the whole point. There is a strong bias against anything that
comes from a YEC source. In fact, it is so strong that anything
coming from a YEC source can be automatically ignored... not even
answered in any sort of serious manner. As it turns out, the quotes
themselves are not misleading in this case. They actually do
represent the thinking of the early to late 1980's concerning the
theory of plate tectonics. The 1990's may have resolved these issues,
but I doubt it as I have seen recent discussions about this issue that
seem to indicate no greater agreement as to the actual mechanisms
involved.
> You know this too, or you would
> do the honest thing. Remember that reference to a slug? You keep denying
> that you act like one.
Really? Still the "slug" thing? You would like to think so.
However, I have been quite honest and up front with you, especially
you. I have told you who I am (a real name and not a pseudonym),
where I work, my educational and cultural background, what ideas are
my own and what ideas have come from elsewhere, that I believe
evolutionary sources are generally better than YEC sources, that I
have been wrong when I see that I am wrong, that I am biased, and a
number of other things that few others in this forum are as willing to
admit or reveal. I have also made a conscious attempt to respond to
those who attack me personally, such as yourself, in a courteous an
professional manner. Really now, you still want to call me a slug?
If so, fine. I'm not here for you or to change your mind. Your
beliefs on the topic of evolution are really is not my concern. I am
here for myself and to refine my own thoughts about a very wide range
of issues that I find personally intriguing. Your passion, however,
is admirable.
> How do all these quotes help your idea of how the plates move.
They don't. They are only presented to question that idea that
anybody really knows how they move. We all believe that they do move
and have moved, but exactly how they move is still generally not
understood.
> Remember
> the YEC guys think that the plates all moved to their present positions in
> just one or a few years. Doesn't look like that is possible for deep
> rooted plates, does it?
It is true that YECs in general think that the plates have moved
rapidly in the past and have arrived at their current positions over
the course of several thousand years, but certainly not millions of
years. The fact that the continents themselves seem to fit together
fairly well, speaks in favor of their separation and relative
movements. However, the fact that they STILL fit together so well is
interesting if this separation occurred 200 or so million years ago.
One might think that erosive forces such as subduction and general
weathering would have changed the shapes of the continents over the
course of 200 million years so that they would no longer fit so neatly
together. Perhaps not, but I have yet to hear a good reason that
explains their obviously matching shapes over such a long course of
time. Off the cuff, I am thinking that a sudden release of a huge
amount of energy, such as might have been delivered by a very large
asteroid impact, might have split the plates apart with such force
that they moved with relatively high speeds initially, only to slow
down as they crashed into one another, building mountains and ocean
trenches fairly rapidly.
> Ron Okimoto
Sean The Slug
Harlequin
news:fd67d42a.02113...@posting.google.com:
> Ron Okimoto
>
> <snip>
>
>> Not that I don't think that you have read all these papers, but they
>> suspiciously all end in the 1980's.
>
> Obviously I haven't read all of these papers nor did I wish to
> indicate that I had.
[snip]
But you _did_ indicate that you had. When you cite a paper
you are outright claiming to have checked it. If you got
the reference from another source and have not actually
read the paper than you must cite the source were you
actually got the information.
>> Remember the honest thing to do is to
>> cite your actual source.
>
> Oh please.
Oh please is right. There is simply NO exceptions to
the requirement that the actual source of information
be cited.
> This is not a review for publication here.
That is simply irrelevent. A citation is a statement
of where you got your information -- period.
> This is a
> discussion forum.
And being a discussion forum justifies giving false
citations?
> It's obvious that I took the information from
> another source.
The only reason it was obvious was from the dates of
the citations and what is known about you personally
in this newsgroup.
I didn't even TRY to hide it. It is actually very
> easy to find the source that I took the information from if one so
> chooses. Do you think I thought that you guys wouldn't figure this
> out? Not a chance! I knew that you would know that this was
> secondary source material. It is blatantly obvious.
[snip]
This sounds a lot like after the fact rationalization.
Saying that it should be obvious is not a legit excuse
nor does it make it justifiable. From now on,
give your actual source of information explicately and do not cite
what you have not personally examined. If you got information from
an article on web cite it and people in the newsgroup can check
examine its references.
And besides, it is less work on you to simply give your actual
source of information. Unless of course your are simply cuting
and pasting large section of another source. But I hope you
would not do that for very obvious reasons...
Keith Littleton
in Message-ID: <fd67d42a.0211...@posting.google.com>
Sean...@juno.com (Sean Pitman M.D.) wrote:
>There have been many who have asked me to specifically
>reply to Keith Littleton's recent "POTM" on talk.origins.
>I have been busy with other interests lately, but I
>finally decided to make a response. Keith did raise
>some very good points. After considering these points,
>I have some more questions that I present line-by-line
>as they arise:
If Sean can take the time to respond to my POTM, I
certainly can reply to his reply. I warn people that
this is very long post. :-)
>>genera technically speaking, the modern coelacanth of
>>the genera Latimera, has no fossil record. Only the
>>order and suborder that it belongs to has.
>>
>>If a person either goes to the nearest college library
>>to research this topic or requests books by
>>interlibrary loan, he / she can find:
>>
>> Coelacanth" W. W. Norton & Company, New York and
>> London, 1991 ISBN 0-393-02956-5
>>
>> On page 78, last paragraph of that book, he would have read:
>>
>> "One point has to be emphasized; The living coelacanth
>> is not a living fossil in the very strict sense that
>> members of the species L. chaumnae itself have ever
>> been found as a fossil. In fact, no other species
>> assignable to the Genus Latimeria has been found as a
>> fossil either. Latimeria and the Cretaceous fossil
>> Genus Macropoma are quite closely related, and we
>> could possibly include them in the same family. Beyond
>> that, all fossil coelacanths belong to the order
>> Coelacanthini."
>
>Kingdom: Anamilia
>Phylum: Chordata
>Class: Osteichthyes (bony fishes)
>Order: Coelacanthini
>Family: Sarcopterygii
>Genus: Latimeria
>Species: chalumnae
-
What does this Prove?? :-) :-) From what I have read
everybody agrees that the modern coelacanths belong to
the genera Latimeria
-
>Very interesting comments.
-
Pitman's comments are very interesting because what Forey
(1998) states and illustrates in "History of the
Coelacanth Fishes" completely refutes what Mr. Pitman
has to say below.
-
>However, it seems to me that you over emphasize the
>differences between the living species Latimeria
>chaumnae, and the fossilized species. The statement
>above that "no other species assignable to the Genus
>Latimeria has been found as a fossil" seems to me to
>be a bit misleading.
-
According to Forey (1998), which you cite below for some
unknown reason, I haven't overemphasized the differences
between the living species, Latimeria chaumnae, and the
fossilized species. Forey (1998) presents both data and
number of observations that demonstrated that Mr. Pitman
is quite wrong about my statement being misleading. If
anything, Mr. Pitman's use of Forey (1998), below, to
support his position extremely misleading.
-
>The fact of the matter is that the skeleton of Macropoma
>lewesiensis, which is known from the upper Cretaceous,
>is virtually identical to that of the coelacanths caught
>off Sodwana Bay, , and differs little from the skeleton
>of most Devonian coelacanths. (Forey, P. 1998. History
>of the Coelacanth Fishes. Chapman & Hall.)
-
The fact of the matter is that Forey (1998) provides
explicit detail about the distinctive differences
between Macropoma lewesiensis and Latimeria chalumnae.
There is a picture of both Macropoma and Latimeria at:
http://www.scienceinafrica.co.za/2002/february/coela2.htm
Looking at the picture, a person can see substantial
differences in the fins, tail, lobe fin, and drastic
changes in the structure of head. Mistaking Macropoma
and Latimeria the same animal is like mistaking
Chimpanzees and Baboons for the same animals. Neither
of these genera are virtually identical to each other
as significant differences does exist between the two.
-
>There seems to be a tendency to place very similar
>fossils in different categories based primarily on the
>fact that they obviously lived so far apart in time that
>they can't possible be members of the same species.
>This practice seems to be the rule rather than the
>exception.
-
Mr. Pitman is wrong again in his rather imaginative and
wildly inaccurate understanding of paleontology. The
degree to which different fossils live apart in time has
nothing to with how fossils are classified. If he and
other Young Earth creationists would look objectively at
fossils like Macropoma lewesiensis and living animals
like Latimeria chalumnae, they would find there do exist
significant differences and that these differences are
significant enough to prove that they are different
animals. Their similarities only show that they are very
closely related with Latimeria chalumnae likely having a
coelacanth very much like Macropoma lewesiensis as its
ancestor. The main difference between coelacanths and
main other orders is that they have evolved at a much
slower rate than them. There is nothing in the various
models of evolution that require that different orders
must evolve all at the same rate. However, Young Earth
creationists, as far as "living fossils" simply deny
that obvious differences exist and engage in
postulating all sort of fiction about how conventional
paleontologists defines species and genera in order to
deny that these differences do exits.
A brief explanation of how fossil are named can be found
in page 3 of the "Fossil Record by Clifford A. Cuffey at:
http://www.gcssepm.org/special/cuffey_03.htm
Part of problem is that popular articles about the
coelacanth tend to be very careless about how they
discuss the coelacanths. To catch the attention the
attention of the reading public, such articles over-
exaggerate and hype the "living fossils" angle and end
up over-exaggeration the similarities between living and
fossil coelacanths. As a result, when people get most of
their information about coelacanths form popular
articles, instead of bothering to read and understand
what has been published in the technical literature,
they end up with wildly wrong-headed ideas of what they
are talking about.
-
>So, to say that the L. chaumnae species has never been
>found in the fossil record seems to me to be stretching
>it a bit since this species classification is based
>on very minor morphologic differences that are clearly
>within the range of intra-species variation if the two
>fish were swimming side by side today. It's kinda like
>putting the French and Italians in different genus
>categories.
-
The differences between Latimeria and Macropoma are not
"very minor morphologic differences that are clearly
within the range of intra-species variation" as was quite
incorrectly and laughably stated. The claim that
Latimeria and Macropoma are no different than French and
Italians is simply not substantiated by the
characteristics of these genera as is quite evident in
the picture at:
http://www.scienceinafrica.co.za/2002/february/coela2.htm
Looking at this picture, a person can see extensive
differences in the shape of skull and the bones that
compose it, the lobe fin, tail, and disappearance of
bones from the upper and lower fins. These differences
are why led Thompson (1991) stated:
"One point has to be emphasized; the living coelacanth
is not a living fossil in the very strict sense that
members of the species L. chaumnae itself have ever
been found as a fossil. In fact, no other species
assignable to the genus Latimeria have been found as
a fossil either. Latimeria and the Cretaceous fossil
genus, Macropoma are quite closely related, and we
could possibly include them in the same family. ..."
The fact there is some question about whether Macropoma
and Latimeria even belong to same family is indicative
that despite the similarities between these genera,
the differences between are real and significant enough
to exclude the possibility that they are either the same
species or genera as Mr. Pittman advocated.
References Cited:
Forey, P. L. (1998) History of the coelacanth fishes.
Chapman and Hall, London.
Thompson, K. S. (1991) Living Fossil: Story of the
Coelacanths. W. W> Norton And Company, NY
-
-
The fact of the matter is that there is an huge amount of
evidence out that demonstrates that subduction is a real
and ongoing process and large amounts of sediments and
ocean floor have been subducted back down into the mantle.
The process of subduction can be inferred from focal
mechanisms of earthqukes, seismic imaging of the Earth's
crust and mantle, and the use of global positioning and
satellite laser ranging systems. There are numerous web
pages about all of this to be found on the Internet.
1. Modern plate tectonics
http://earth.leeds.ac.uk/dynamicearth/plates_move/active_tectonics/index.htm
2. Subduction zones - Lecture by Rob van der Hilst
http://quake.mit.edu/hilstgroup/MantleConvection/310398_notes.html
>Evidence of significant subduction as a means for
>sediment removal seems to be rather lacking as far as
>I can tell.
Mr. Pitman is quite wrong about claiming that the
"Evidence of significant subduction as a means for
sediment removal seems to be rather lacking as far as
I can tell." For example using seismic tomography,
conventional geologists can map, in the subsurface, the
large slabs of oceanic sediments and crust that have been
subducted over the millions year into the mantle. The
volume of these slabs demonstrate that large volumes of
oceanic sediment and crust have been subducted into the
mantle. Some web pages illustrating this evidence are:
1. Subduction On Creationism & Plate Tectonics
http://www.tim-thompson.com/subduction.html
2. The Fate of Slabs Inferred from Seismic Tomography
and 130 Million Years of Subduction by Lianxing Wen and
Don L. Anderson.
http://www.gps.caltech.edu/~wen/Sub130Paper/sub130.html
3. Seismic Tomography
http://www.aeic.alaska.edu/Input/martin/physics212/seismictomo.html
In fact volcanic chains such as the Japanese Islands, the
Cascade Mountains, Indonesia, and many others consist
largely of the oceanic sediments and crust that was
subducted and partially melted to create the magma that
was extruded to form these volcanic mountains.
-
>There is even argument as to what forces might be stable
>enough to drive such prolonged subduction of huge
>portions of the earth's crust over the course of
>hundreds of millions of years.
-
Actually there a considerably number of papers, numbering
in the several hundreds. The overall consensus of
numerous attempts to model the process of subduction is
that it is indeed very stable and capable of prolonged
subduction of the Earth's crust over hundreds of millions
of years.
-
>In any case, there have been recent finds of coelacanths
>off the coast of the Comoro Islands in 1998 that do not
>live in very deep water (~200m) or in caves. How did
>these coelacanths survive without being fossilized over
>the course of 80 million years?
-
The fact of the matter is that the Comoro Islands are a
volcanic archipelago of four islands and several islets
located in the western Indian Ocean about 188 miles east
of Africa and 188 miles northwest of Madagascar at the
northern end of the Mozambique Channel that separates
Africa and Madagascar. The ocean surrounding the Comoro
Islands ranges in depth from 3,400 to 3,700 meters
(10,400 to 11,300 feet) (Department of Defense 1992,
1996). Therefore, by any standard, the ocean "off the
coast of the Comoro Islands" is very deep water that
completely falsifies Mr. Pitman's statement about the
coelacanths offshore of the Comoro Islands don't live in
very deep water.
Contrary to what Mr. Pitman stated above. Even if the
coelacanths live in the upper 100 to 300 meters (304 to
914 feet) of the ocean, when they die their remains will
eventually accumulate at the bottom of the Mozambique
Channel. Undoubtedly, the bones of coelacanths have
dropped of the bottom of the Mozambique Channel and
been buried and fossilized in these sediments. However,
it should be quite obvious that none of these
hypothetical coelacanths fossils are in a position to be
found by conventional geologists because of the lack of
outcrops of any of these sediments on land. Also, the
great depths precludes their recovery. Undoubtedly,
fossils of these coelacanths exist. However, they occur
in a position where it is impossible for Mr. Pitman to
expect that conventional paleontologists can recover
them. Whenever the Mozambique Channel closes in the far
geologic future, the sediment and Comoro Islands will
likely be either largely destroyed or intensively
metamorphosed to the point of destroying the vast
majority of coelacanth fossils that have accumulated at
the Mozambique Channel.
For a map showing the bathmetry of the ocean floor
around the Comoro Islands a person can go to:
http://oceancurrents.rsmas.miami.edu/atlantic/img_topo2/agulhas2.jpg
References Cited:
Department of Defense (1992) Comoros Islands, Indian
Ocean. bathmetric map, scale, 1:300,000. map number
61ACO61310
Department of Defense (1996) Tanjona Bobaomby to Nosy-Be.
bathmetric map, scale 1:300,000. map number 61ACO61410.
-
>>It is interesting. I would be very interested in why
>>Mr. Pitman expects paleontologists to be able to find
>>fossils in sediments that are either underwater and
>>buried beneath younger sediments or consist of badly
>>deformed even metamorphosed sediments. If this
>>argument is invalid, Mr. Pitman should have absolutely
>>no trouble at all pointing specific outcrops of
>>sedimentary strata where a person could look for the
>>remains of coelacanths.
>-
>The vast majority of sedimentary layers in the geologic
>column were formed underwater. I am rather surprised
>that anyone would argue this point.
-
Mr. Pitman seems to be unaware of the fact that because
sediment was deposited underwater fails miserably to
means that a person would have any chance of finding
in them any fossil coelacanths dating to the last 80
million years
Given that coelacanths disappeared from non-marine
environments, e.g. lakes and streams during the Jurassic-
Cretaceous, it is rather useless to look for fossils of
coelacanths dating to the last 80 million years in
underwater sediments deposited in lakes. For example,
the strata of the Green River Formation were deposited
underwater, but it would be rather silly for anyone to
argue that coelacanths should be found in these sediments
because they are formed underwater. Contrary to what Mr.
Pitman believes, it is rather hopeless, if not rather
laughable, for someone to look for coelacanths in
the deposits of a freshwater interior lake for fossils
of coelacanths that are 80 million years or less old.
The best chance that a person has for finding fossil
coelacanths would be in underwater sediments deposited in
ocean basins adjacent to coasts and oceanic islands that
that now outcrop onshore. The fact of the matter is that
such onshore outcrops of deep sea sediments dating to
the last 80 millions are quite rare. In addition, those
which exist, have often been so very badly mangled by
metamorphism and tectonics as to have destroyed any
fossils they might have contained. As a result, the
absence of fossils coelacanths for the last 80 million
years can easily be explained from the paucity of rocks
of the right age and sedimentary environment to contain
fossils.
-
>For example, it is thought that all of the layers in the
>Grand Canyon, save the Coconino Sandstone layer, was
>formed underwater.
-
Mr., Pitman is very incorrect "it is thought that all of
the layers in the Grand Canyon, save the Coconino
Sandstone layer, was formed underwater." Contrary to
what Mr. Pitman stated, conventional geologists have
argued that other strata exposed in the Grand Canyon in
addition to the Coconino Sandstone, are either in part
or completely of nonmarine origin. These other strata
are:
1. The Watahomigi Formation (30 to 90 meters (100 to
300 ft) thick) in the Supi Group contains mudstone
redbeds, which are regarded as terrestrial coastal
plain deposits, in addition to marine carbonates.
2. The Manakacha Formation (46 to 90 meters (150 to 300
ft) thick) in the Supai Group consists of red mudstones
and quartz sandstones that are, respectively, interpreted
to be either alluvial or coastal plain sediments and the
deposits of sand dunes.
3. The Wescogame Formation (30 to 61 meters (100 to 200
ft) thick) in the Supai Group is regarded as being much
of the origin as the Manakacha Formation. It interfingers
with marine carbonates.
4. The Esplande sandstone in Supai Group is regarded as
consisting of fresh water, lacustrine carbonates, eolian
sandstones, and terrestrial redbeds.
5. Hermit Shale (15 to 240 meters (50 to 800 ft thick )
is regarded to consist of sediments deposited in coastal
plain and alluvial flood plains.
6. In the eastern Grand Canyon, the Brady Canyon
member (85 meters (280 ft) thick) of the Toroweap
Formation is regarded as being of terrestrial origin,
eolian dunes, although it grades westward into marine
limestones.
As a person can read above and in Beus and Morales
(1990), There are several stratigraphic units, in
addition to the Coconino Sandstone, which conventional
geologists regard to be nonmarine in origin. The
statement "it is thought that all of the layers in the
Grand Canyon, save the Coconino Sandstone layer, was
formed underwater." is simply not true.
Reference Consulted
Beus, S. S., and M. Morlaes (1990) Grand Canyon Geology
Oxford University Press, New York.
-
>Yet, there it is for all to see, above water.
-
Yes, the strata exposed in the Grand Canyon is all above
water for all to see. However, it is completely useless
for finding fossils of coelacanths that are less than 80
million years old as Mr. Pitman clearly doesn't seem to
understand. First, even the marine strata of the Grand
Canyon is a hopeless place to look for the "missing"
fossil coelacanths of the last 80 million years. The
youngest strata exposed strata in the Grand Canyon is the
Kaibab Formation is regarded as being 250 to 350 million
years old. As a result, it is 170 to 270 million years
too old to contain any coelacanth fossils that would
fill in the 80 million year old gap in the fossil record
of coelacanths being discussing. Because it, and the
underlying marine strata are older than 80 million years,
a person might find some coelacanth fossils in the
shallow marine sediments. However, none of these fossils
will be of the right age to fill in the gap in the fossil
record of coelacanths from now to 80 million years ago.
There are sediments in the area of the Grand Canyon that
have accumulated over the last 80 million years. However,
the majority consist of sediments of nonmarine in origin.
Thus, it is obviously hopeless strata in which to look
for missing coelacanths. It might be possible to find
fossil coelacanths in the Mancos Shale. Unfortunately,
this unit dates to the beginning of the interval, for
which coelacanth fossils are lacking, and any fossils
from it would do nothing to close the gap. The only
conclusion that a geologist can come to is that Mr.
Pitman's proposal to look either the Grand Canyon
or Grand Canyon region for the remains of coelacanths
will do nothing to solve the problem. Maybe, Mr. Pitman
might be better off looking in the Paleocene of Denmark
where a bone, possibly from a coelacanth, has been
found by Orvig (1986).
---
Of course, if Mr. Pitman still believes that he can find
fossils of Latimeria chalumnae in the Grand Canyon, I
will not try dissuade him from making a fool of himself
and wasting money. (of course, when he comes back after
searching the area for five years and finding nothing,
I will post a loud and clear, "I told you so" to
talk.origins newsgroup.
The geological section that lies above the strata exposed
in the Grand Canyon is discussed in "Jurassic - Cenozoic
Strata of the Colorado Plateau" at:
http://www.geocities.com/earthhistory/grand2b.htm
and in "Triassic Strata of the Colorado Plateau" at:
http://www.geocities.com/earthhistory/grand2.htm
Reference Cited:
Orvig, T., (1986) Vertebrate bone from the Swedish
Paleocene. Geologiska Foreningens i Stockholm
Forhandingar. vol. 108, pp. 139-141.
-
>The coelacanths that are fossilized, also lived
>underwater once upon a time. The argument here is that
>their habitat was more conducive to fossilization than
>the habitat of the modern coelacanths. Conduciveness is
>a bit different from preservation potential however.
>Subduction arguments do not argue so much against
>conduciveness, but against preservation potential.
-
How does "Conduciveness" differ from "preservation
potential"? Since "Conduciveness" is totally dependant
on preservation potential, separating the two is rather
meaningless in this discussion. But I guess whatever
turns you on is OK with me. :-) :-) Still Mr. Pitman
doesn't make much sense here.
-
>However, we do have supposedly ancient deep sea
>sediments preserved in the fossil record.
-
This is true. The problem is that much of the deep sea
sediments, which survive destruction, are far too old
to contain coelacanth fossils from the 80 million year
gap in their fossil record. There are very few and very
restricted places where relatively undeformed deep sea
strata from the 0 to 80 million year period are exposed.
These outcrops are so restricted that it is entirely
possible for coelacanths to have lived off the coasts of
Indonesia, South Africa, and Comoros Islands for the past
80 million years and not find any evidence of them
because there are no onshore exposures of sedimentary
marine rocks containing their fossils in these regions.
-
>Somehow they managed to survive destruction by
>subduction.
-
If Mr. Pitman would bother read about the concepts he
trashes, he find that a small percentage of oceanic crust
and sediments, along with the tops of seamounts, is
scraped off during subduction and accreted to the
continental. The survival of small pieces of oceanic
strata is perfectly explained within the subduction
model. Thus, the "somehow" in this sentence is entirely
unnecessary.
-
>In any case, more populations of coelacanths have been
>found that live in shallower waters that are not
>protected by deep sea caves.
-
Obviously. Mr. Pitman means the coelacanths found in 60
meters (196 feet) of water off of the coast of St. Lucia
Wetland Park in South Africa. Still 196 feet is awfully
deep water that in which it virtually, if not actually,
impossible to any sort of fossil hunting in even if
outcrops of fossil bearing strata existed on ocean
bottom.
-
>Yet, these fishes somehow avoided fossilization as well.
-
Again, Mr. Pitman doesn't understand why coelacanth
fossils are not found in South Africa. It has nothing to
do with the coelacanths magically avoiding fossilization.
Undoubtedly, coelacanth die and sink to the bottom where,
at least, a percentage are buried, covered with
sediments, and are fossilized. The problem is that all of
this is occurring deep in the ocean. As a result, any
fossil South African coelacanths lie buried beneath water
and sediment where no paleontologist or geologist can
find them. The South African coelacanths live in
shallower waters than the others, 60 meters is still far
too deep for conventional geologists and paleontologists
to go fossil hunting in.
-
> This seems rather strange to me.
-
There is nothing strange about this. If there are no
outcrops where geologists and paleontologists can find
fossil coelacanths, no fossil coelacanths will be found.
An example of outcrops control what fossils geologists
and paleontologists find occurred in Louisiana
"recently". Prior to the middle 1990's vertebrate fossils
from the Miocene strata of Louisiana were unknown, except
for a fragment ancestral elephant tooth even after over
40 years of study of the Fleming Group. During the 1990's
erosion caused by military maneuvers and a fill dirt pit
open up five to six exposures on Fort Polk. In less than
five to six years of study of these exposures over 160
species of fossil animals were recovered from these
manmade outcrops. The Fleming Group contained numerous
fossils and many geologists and paleontologists studied
the Fleming Group. It is just that outcrops of fresh,
fossil bearing strata didn't exist. As in Louisiana, if
outcrops of strata containing the fossil coelacanths are
not available for geologists to look at, fossils of
coelacanths cannot and will be found.
-
>Of course, coelacanths are not the only ones to
>seemingly be raised up after tens of millions of years
>of extinction. There are a large number of other
>fossils to include entire orders of creatures that
>disappear from tens of millions of years, and then
>reappear suddenly in the fossil record. These examples
>are so common that they have been given the name,
>"Lazarus Taxa."
-
There is nothing puzzling or mysterious about all of
this. If strata containing fossils of these animals are
either not exposed or don't exist, then it is completely
ridiculous to expect fossils of these animals to be
found.
-
>>>Fossilization requires rapid burial or else decay will
>>>obliterate all traces.
>This is not completely true. Bones can survive for over
>a year before being buried.
-
>This depends upon the environment in which they are
>deposited as well as the size of the bones.
-
This is true. Far more important than rapid burial, the
location of where the remains of an animal come to rest
is likely the most important factor in determining
whether or not they are preserved. If preserved, it also
determined how well or how badly the remains will be
preserved
-
>Also, well preserved fossils of completely intact
>specimens, to include soft tissue impressions in fine
>detail, as is the case with many of the coelacanth
>fossils, requires rapid burial.
-
Rapid burial is a major, although not always a necessary
part of the preservation of completely intact specimens
including impressions of soft parts. However, Mr.
Pitman's is completely wrong that a global catastrophe,
e.g. the Noachian Flood, is needed for rapid burial.
In case of the Mazon Creek fossils, the animals and
plants were rapidly buried when periodic floods dumped
freshwater and sediment into a deltaic estuary / bay
(Baird 1990, pp. 279, 281, Baird et al. 1986). Once
buried, bacterial decay of these organisms caused the
precipitation of a siderite concretion that quickly
encased it and preserved its form (Baird 1990, Fig. 3).
The organism itself is not really fossilized, but left
as a phosphatic film or impression preserved by the
concretion as is characteristic of all of the soft-
bodied fossils found in these concretions including the
famous Tully monster. There are many non-catastrophic
processes that cause rapid burial of fossils.
References Cited:
Baird, G. C. (1990) Mazon Creek. In D. E. G. Briggs and
P. R. Crowther (ed.), Palaeobiology: A Synthesis. Oxford
Blackwell Scientific Publications, London, pp. 279-282.
Baird, G. C., S. D. Sroka, C. D. Shabica, and G. J. Kuecher
(1986) Taphonomy of Middle Pennsylvanian Mazon Creek area
fossil localities, Northeast Illinois: significance of
exceptional fossil preservation in syngenetic concretions.
Palios, vol. 1, pp. 271-285.
Web Pages:
Mazon Creek fossils at:
http://museum.state.il.us/exhibits/mazon_creek/index.html
http://museum.state.il.us/exhibits/mazon_creek/about_mazon_creek.html#HowFormed
Pictures of Mazon Creek Fossils can be found at:
1. http://museum.state.il.us/exhibits/mazon_creek/
about_mazon_creek.html#Animals
(The above URL needs to be reassembled to work)
2. http://search-desc.ebay.com/search/
search.dll?MfcISAPICommand=GetResult&query=%22mazon+creek%22&cgiurl=http%3A%2F%2
Fcgi.ebay.com%2Fws%2F&ht=1&from=R10&currdisp=2&itemtimedisp=1&st=2&SortProperty=
MetaEndSort&srchdesc=y&BasicSearch=
(The above URL needs to be reassembled to work)
-
>>In the case of shells, they can be washed around for
>>decades, even hundred of years, before they are finally
>>buried in the sediment to become fossils.
>
>This also depends upon the environment and the size of
>the shell. The fact of the matter is, even in the best
>of circumstances, even shells are degraded fairly rapidly
>in exposed environments. They do not last for hundreds
>of years of open exposure and weathering.
-
This not always true. Shell can, in fact, exist for
hundreds of years of lying on the ground and weathering.
Proof of this are beach ridges in the Louisiana chenier
plain and elsewhere that are composed of shell and which
have not weathered away after a couple of thousand years.
Addition proof consists of Native American shell middens
composed entirely of shell, which haven't weathered away
after thousands of years of weathering. The fact that
even after a thousand years or more, a person can still
find shell middens and shell beaches in Louisiana and all
over the world clearly refutes Mr. Pitman's argument that
shells do not last for hundreds of years in any situation
or location. However, the local environment does play a
major role in the durability of shell.
In marine environments, it is true that shells are not
continuously exposed at the surface. Rather as they "wash
around", they are periodically buried and unburied by
storms and the daily shifting of sand along the beach and
within the nearshore environment. The more time a shell
spends buried in the sand and the more solidly built a
shell is the more likely it will survive long enough to
be eventually buried and preserved as a fossil.
Finally, taphonomists have conducted studies with shells,
in which they placed shells on the bottom of specific
areas of the ocean. The locations were marked and tagged
so they could come back to the location and observed what
happened to the shells. One important finding was in
some areas characterized by mud bottoms where the shells
became buried without any sedimentation happening at all.
In this case, the churning of the ocean bottom by various
organisms was sufficient to bury anything left on it. In
addition, Behrensmeyer (1991:606) found on land that
bones could be rapidly buried by trampling. In certain
circumstances not only is a global catastrophe unneeded
for the rapid burial of shells and bones, but also the
deposition of any sediments is unnecessary for shells and
bones to be buried. Whether a bone or shell will buried
and how fast all depends on the local environment in
which it comes to rest.
References Cited:
Behrensmeyer, A. K. (1991) Vertebrate Paleoecology in a
Recent East African Ecosystem. In J. Gray, A. J. Boucot,
and W. B. N. Berry, eds., pp. 591-615, Communities of
the Past. Hutchinson Ross Publishing Co, Stroudsburg.
-
>In any case, we are not talking shells here, but fish
>that are preserved intact, often with delicate soft
>tissue impressions also preserved in fine detail.
-
However, intact fossil fish are a very rare, very small
percentage of all the fossils to be found. Shells,
including the tests of foraminifer and other
microfossils, and isolated bones likely comprise, I
would guess, about 99.999+ percent of the fossils to be
found. Complete and intact fossils of fish and other
vertebrates are an insignificant percentage all fossils
that can be found in the geologic column. The fossil fish
with soft delicate tissue preserved are likely only a
minority of all of fossil fish with intact skeletons that
are found. Although showy, eye-catching, and, thus, easy
to hype, intact fossil fish are completely
unrepresentative and atypical of fossils that are
normally found in sedimentary rocks.
To some extent the focus that Young Earth creationists
have on the exceptional intact fossil fish skeleton and
soft bodied fossils is in part a debating technique.
First, these fossils, unlike the average shell and
disarticulated bone, are for more showy and eye-catching.
They attract the attention of the general public to whom
they are trying convert to their point of view. Also, if
Young Earth creationists can also make the general public
falsely believe that soft-bodied fossils and articulated
fish and other vertebrate fossil are far more common and
abundant than they really are, they make the occurrence
of these fossils a matter far more mysterious than
it really is. Thus, it is important to emphasis that
intact fossil fish are in fact quite rare in respect to
the disarticulated bones of fish and articulated
skeletons are grossly atypical in terms of the state in
which fossils are normally preserved.
From just the very small percentages of intact fossil
fish found relative to disarticulated fish bones and
all other poorly preserved fossils, it is quite obvious
that the conditions under which intact fossil fish are
created are overall rare. In addition, the processes,
which create fossil fish are very limited in the area
over which they operate. This is not the signature of
a global catastrophe, but rather an limited area, e.g.
a very large or lagoon, and time during which the
conditions are just right for the fossilization of fish,
-
>This level of detail requires very rapid burial.
>Only in of the fossilization of soft parts is
>immediate burial required.
-
When soft tissue is fossilized, rapid fossilization and
eventual burial are general requirements. However, as
noted above, a global catastrophe is not required for
either rapid or eventual burial to take place. Even when
rapid burial occurs, it can be caused by any number of
non-catastrophic processes, such as a volcanic eruption,
landslide, undersea slump, single turbidity current,
river flood, diurnal tidal currents, hurricane, typhoon,
and so forth. Only someone completely uninformed about
these and similar geologic processes would argue that
only a catastrophic event, e.g. a mythical and
imaginary Noachian Flood to explain the rapid burial of
fossils.
Glen Morton discusses "Non-Catastrophic and Modern
Fossilization" at:
http://www.glenn.morton.btinternet.co.uk/fossilization.htm
In a brief review published research on how fossils are
made, Glenn documents numerous papers, which document
modern examples that refute Mr. Pitman's claim that a
world-wide catastrophe of any sort is needed for the
preservation of soft-bodied fossils.
-
>At least at this level, but also at the level of
>intact skeletons.
-
Rapid burial helps, but is not always absolutely needed
for the preservation of intact fossil fish skeletons.
Briggs et al. (1993) noted that the decay rate can be
inhibited by both temperature and salinity and the
process of fossilization may continue for weeks. Rapid
burial is a great asset in terms of preservation, but
fossilization can begin even before the fossil fish is
buried. In cases where either a fossils falls into
toxic anoxic or highly saline bottom waters that
preclude scavenging.
Again, a person needs to remember that the preservation
of intact skeletons, whether they be fossil fish or any
other vertebrates are quite rare events. The vast
majority of vertebrate fossils are not intact skeletons.
The vast majority, which lie in the 99.999+ range of
vertebrate fossil, are disarticulated fossils. Many of
these scattered bones, commonly show the effects of
weathering and having been gnawed on, which clearly
demonstrate that many fossils were not rapidly buried.
In fact the effects of weathering and animals on the
bones show that they lay exposed for an extended period
of time and were **not** the remains of animals killed
and rapidly buried by a global catastrophe. Of course,
Young earth creationists don't want to talk about these
fossils. Rather, they want to focus largely on the more
showy and attention getting intact fossils that are quite
unrepresentative of the typical fossil a person normally
finds in the field.
There is additional discussion in the web page on
"Non-Catastrophic and Modern Fossilization" at:
http://www.glenn.morton.btinternet.co.uk/fossilization.htm
-
>>This all has been documented by direct field
>>observation and other studies. Contrary to what Mr.
>>Pitman incorrectly claims, the hard part of animals
>>can persist for a significant period of time before
>>being finally buried.
>
>Generally not. Even "hard parts" weather fairly
>rapidly in open environments.
-
Contrary to what Mr. Pitman claims, bones does not always
weather rapidly in "open environments". If a person reads
through the published, a person finds that the rate at
which a fossil bone weathers all depends the location of
the bone in questions. On acidic soils and where there is
wide variation in temperature and moisture, the rates of
bone weathering can be quite rapid as Mr. Pitman states.
In other environments and on calcareous soils, bones can
last 8 to 15 years, which by my standard is not "fairly
rapidly" as documented by Behrensmeyer (1991). The is a
relatively long period of time during which at least a
few of these bones can be either buried by trampling,
wash into a nearby stream, or buried by river flood and
preserved and fossilized.
-
>Intact skeletons are especially prone to disarticulation.
-
This is true. However, this is why the vast majority of
vertebrate fossils found are disarticulated. Conventional
geologists and paleontologists would agree on this point.
-
>>In fact, the degree to which many fossil shells are
>>either encrusted or have been bored by other organisms
>>and bones show signs of either weathering or gnawing
>>demonstrates that they were not rapidly buried before
>>being fossilized.
-
>Encrustation and boring can occur very rapidly after
>death and even before the death of shelled creatures.
>Encrustation is quite commonly observed in living
>animals that walk along with entire colonies of
>other types of creatures living on their backs.
>Keeping a shell clean of critters is a constant battle
>for the owner of a shell.
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Encrustation and boring can occur "rapidly". However,
relative a global flood that lasts about an year, the
rates of encrustation and boring can be quite "slow".
It takes several weeks to a month for the degree of
boring seen in many fossil shells. At this rate, a bed
containing bored and encrusted shells represents a
period of several weeks during which no sedimentation
occurred. When a person finds dozens to hundreds of such
beds within thousands of feet of sediment allegedly
deposited during such a flood, the amount of time that
sediment wasn't being deposited, while the shells weren't
being bored, during the accumulation of this stack of
sediment far exceeds the amount of time that Noah's
Flood is alleged to have taken place. The time during
which encrustation and boring was taking place would
have required unbelievable and unrealistic rates of
sedimentation even when the time for the accumulation
of these sediments happened to be a positive number.
Mr. Pitman's comments about encrusting and boring "even
before the death of shelled creatures." fails miserably
as an explanation. The types of borings and encrustation
that are seen on many fossils are simply not the type
which are formed during the life of an animal. They are
the type which form after it dies. Some examples, are the
encrusting fossils found on the articulated skeleton of a
Basilosaurus found at Montgomery Landing in Louisiana
(Lancaster 1986) and the encrusted ammonites found in
Jurassic black shale deposits, known both as the
"Posidonienschiefer" and "Posidonia Shale" which occur
in southwestern Germany. Within marl beds, that lie
between beds of black shale, fossils of ammonites lying
on their site are abundant. These ammonites are always
encrusted and bored on the side facing upward indicating
that the encrustation and boring occurred after the
ammonite had died and its shell had settled flat on the
bottom of the sea floor. Such ammonites must have lay
on the bottom for months while other animals grew on it
and bored into it shell. The encrusting fossils show
that only after a period of many months or even years
was the ammonite finally buried (Kaufman 1981,
Wild 1990).
In the "Posidonienschiefer" and "Posidonia Shale",
Kaufman (1981) and Wild (1990) observed direct evidence
of "bacterial decay and scavenging" of ichthyosaur
fossils also indicating long period during which the
upper surface of their carcasses were exposed before
being buried. The evidence of decay in many ichthyosaur
skeletons, although still articulated, and the
scavenging indicate that these sediments did not
accumulate at a catastrophically rapid rate as claimed
by Young Earth creationists. They also indicate that these
and better preserved intact ichthyosaur skeletons are
not indicative of rapid burial associated with
catastrophic event.
References Cited
Kaufman, Erie G. (1981) Ecological reappraisal of the
German Posidonienschiefer. in J. Gray, A. J. Boucot, W. B.
N. Berry, eds., Communities of the Past. Huthchinson Ross
Publishing Company. Strousburg, PA.
Lancaster, W. C. (1986) The taphonomy of an archaeocete
skeleton and its associated fauna. In J. A. Schiebout
and W. van den Bold, eds., pp. 119-131, Montgomery
Landing Site, Marine Eocene (Jackson) of Central
Louisiana. Gulf Coast Association of Geological Societies.
Wild, R. (1990) Taphonomy; Taphonomy of fossil-
lagerstatten; Holzmaden. In Palaeobiology; a synthesis,
D. E. G. Briggs and P. R. Crowther, eds., pp. 282-28.
Blackwell Science Publications, Oxford, United Kingdom.
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>The fact that there are a significant percentage of
>fossilized shells preserved in pristine condition speaks
>in favor of their rather rapid burial, en mass.
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"Pristine condition" LOL :-) In the real world, there is
a big difference between what a person finds in outcrops
and what is illustrated in the carefully selected
figures that Young Earth creationists use to illustrate
their pamphlets and books. In the field a person would
find that the vast majority of fossils are not in anyway
anything approaching pristine condition. In addition,
the pictures found in scientific journals are biased
towards the well preserved / "pristine" specimens
because those are the specimens most useful for
describing new fossils, discussing taxonomy, and
interpreting the anatomy of fossils. Of course, the
readers of National Geographic and rock, mineral, and
fossil magazines expect to see gorgeous pictures of
fossils in the issues they pay for. The pictures of
fossils published in the religious, scientific, or
popular publications portray an extremely biased view
of the typical condition of the average fossil.
For any collection of pristine shells, there are bed
upon bed of fossil hash in the geologic record. For each
intact skeleton of a fish or any other vertebrate, there
are millions of isolated bones and bone fragment. The
reality of the fossil record is that "fossilized shells
preserved in "pristine condition" are only a very small
percentage of the fossils found in geologic record. The
the vast majority of fossils consists either of fossil /
shell hash or isolated, often broken, pieces of bone.
If "pristine fossils" were as common as Mr. Pitman
believes them to be, the law of supply and demand being
what it is, a person wouldn't find these fossils selling
for tens of dollars to thousands of dollars on Ebay. The
inexpensive fossils are typically either rather beat up,
poorly preserved, or fragments. For example, if there are
"billions and billions" of well-preserved fossil fish in
Old Red Sandstone, as claimed by Mr. Pitman, they should
be easy enough to find where they should sell for only a
few pennies each. Instead, prices for common fish fossils
from the Old Red Sandstone range from 40.00 to 70.00
dollars a fish to 125.00 to over a 1,000 dollars a fish
for the larger and less common varieties. There is no
cartel like DeBeers or OPEC controlling the price of
fossil fish from the Old Red Sandstone.
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>>t this time, enough research has been done by
>>geologists and paleontologists where the proposal that
>>fossilization is catastrophe dependent can easily be
>>demonstrated to be completely refuted.
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Glen Morton briefly reviews this research in "Non-
Catastrophic and Modern Fossilization" at:
http://www.glenn.morton.btinternet.co.uk/fossilization.htm
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When Young Earth creationists, including you, discuss
the topic of "fossilization is catastrophe dependent."
you don't limit yourself to fish fossils. If you are
talking only about fish fossils, you shouldn't use such
a broad, all-encompassing statement like "fossilization
is catastrophe dependent." Instead, you should indicate
that you are specifically discussing fish fossils by
making any statement more specific such as saying
"fossilization of fish is catastrophe dependent".
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