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Overlapping sedimentary rocks

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Friar Broccoli

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May 17, 2013, 12:45:08 PM5/17/13
to

Near my home are Cambrian sedimentary rocks.

Yesterday I noticed a distinct layer with overlapping segments. At
first I thought it was a unique anomalous feature, but then (about 50
vertical feet up - 300 feet farther along/downstream) I saw another
layer that had been laid down at a later time with exactly the same
overlapping characteristics.

(There is a third, less distinct, layer between the two shown)

Here are photos of the two locations:

https://picasaweb.google.com/107817774238317597615/Temp_images?noredirect=1

or

http://goo.gl/qK0Fp


Can anyone suggest how these overlaps might have formed? I have no
clue.

--
Friar Broccoli (Robert Keith Elias), Quebec Canada
I consider ALL arguments in support of my views

Thrinaxodon

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May 17, 2013, 12:50:53 PM5/17/13
to
On May 17, 12:45�pm, Friar Broccoli <elia...@gmail.com> wrote:
> Near my home are Cambrian sedimentary rocks.
>
> Yesterday I noticed a distinct layer with overlapping segments. �At
> first I thought it was a unique anomalous feature, but then (about 50
> vertical feet up - 300 feet farther along/downstream) I saw another
> layer that had been laid down at a later time with exactly the same
> overlapping characteristics.
>
> (There is a third, less distinct, layer between the two shown)
>
> Here are photos of the two locations:
>
> https://picasaweb.google.com/107817774238317597615/Temp_images?noredi...
>
> or
>
> http://goo.gl/qK0Fp
>
> Can anyone suggest how these overlaps might have formed? �I have no
> clue.
>
> --
> � Friar Broccoli (Robert Keith Elias), Quebec Canada
> � �I consider ALL arguments in support of my views

I forget, the name of the process. but, I recall, two plates collide,
and it causes two sedimentary layers, to "turn over on each other".

walksalone

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May 17, 2013, 1:14:33 PM5/17/13
to
Friar Broccoli <eli...@gmail.com> wrote in
news:jnmcp81j6msnd5enj...@4ax.com:

>
> Near my home are Cambrian sedimentary rocks.
>
> Yesterday I noticed a distinct layer with overlapping segments. At
> first I thought it was a unique anomalous feature, but then (about 50

snip

> https://picasaweb.google.com/107817774238317597615/Temp_images?noredire
> ct=1

snip

> Can anyone suggest how these overlaps might have formed? I have no
> clue.

It seems to me, & I am no geologist, what you are seeing is a very small
upheaval. Almost as if a hot spot was trying to become a volcano.
As always, YMWV.


walksalone who could possibly run that down. But I suspect there are many
here much better qualified than I ever will be.


Keep away from people who try to belittle your ambitions. Small people
always do that, but the really great make you feel that you, too, can
become great.
Mark Twain, U.S. Author (1835-1910)

eridanus

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May 17, 2013, 2:03:43 PM5/17/13
to
El viernes, 17 de mayo de 2013 17:45:08 UTC+1, Friar Broccoli escribi�:
beautiful pictures
Eridanus

alias Ernest Major

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May 17, 2013, 2:27:11 PM5/17/13
to
I was about to suggest that you ask in sci.geo.geology, but that appears
to be well and truly dead, with nothing but spam.

My guess is that the beds have been laterally compressed. The main body
of the rocks has deformed, but the layers you photographed were more
rigid, and broke instead. Once broken the compressive forces can slide
the segments along each other.

--
alias Ernest Major

Don Cates

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May 17, 2013, 6:10:48 PM5/17/13
to
My daughter the geologist just arrived for a visit. She says it is a
nice example of a low angle reverse fault. The regional rock was
compressed and the layers slide past themselves in some locations. Above
and below that distinct (probably sandstone) layer is a softer shale.
There would be similar overlaps there but would be difficult to see.

--
--
Don Cates ("he's a cunning rascal" PN)

Friar Broccoli

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May 17, 2013, 6:51:47 PM5/17/13
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On Fri, 17 May 2013 17:10:48 -0500, Don Cates <caHOR...@mts.net>
wrote:

>On 17/05/2013 11:45 AM, Friar Broccoli wrote:
>>
>> Near my home are Cambrian sedimentary rocks.
>>
>> Yesterday I noticed a distinct layer with overlapping segments. At
>> first I thought it was a unique anomalous feature, but then (about 50
>> vertical feet up - 300 feet farther along/downstream) I saw another
>> layer that had been laid down at a later time with exactly the same
>> overlapping characteristics.
>>
>> (There is a third, less distinct, layer between the two shown)
>>
>> Here are photos of the two locations:
>>
>> https://picasaweb.google.com/107817774238317597615/Temp_images?noredirect=1
>>
>> or
>>
>> http://goo.gl/qK0Fp
>>
>>
>> Can anyone suggest how these overlaps might have formed? I have no
>> clue.

.


>My daughter the geologist just arrived for a visit. She says it is a
>nice example of a low angle reverse fault. The regional rock was
>compressed and the layers slide past themselves in some locations. Above
>and below that distinct (probably sandstone) layer is a softer shale.
>There would be similar overlaps there but would be difficult to see.

That could explain why all the shale in the area is so extremely
fragile.

Thanks

Friar Broccoli

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May 17, 2013, 7:03:30 PM5/17/13
to
On Fri, 17 May 2013 11:03:43 -0700 (PDT), eridanus
<leopoldo...@gmail.com> wrote:

>El viernes, 17 de mayo de 2013 17:45:08 UTC+1, Friar Broccoli escribi�:
>> Near my home are Cambrian sedimentary rocks.
>>
>>
>>
>> Yesterday I noticed a distinct layer with overlapping segments. At
>>
>> first I thought it was a unique anomalous feature, but then (about 50
>>
>> vertical feet up - 300 feet farther along/downstream) I saw another
>>
>> layer that had been laid down at a later time with exactly the same
>>
>> overlapping characteristics.
>>
>>
>>
>> (There is a third, less distinct, layer between the two shown)
>>
>>
>>
>> Here are photos of the two locations:
>>
>>
>>
>> https://picasaweb.google.com/107817774238317597615/Temp_images?noredirect=1
>>
>>
>>
>> or
>>
>>
>>
>> http://goo.gl/qK0Fp
>>
>>
>>
>>
>>
>> Can anyone suggest how these overlaps might have formed? I have no
>>
>> clue.
>>

.

>beautiful pictures

A truly idiot proof camera given to me for Christmas by my son's
girlfriend. All I have to do is touch the display and the camera
focuses on that and shoots.

Yesterday I was shooting a hawk in the sky. I touched in another part
of the sky and the camera didn't shoot until I had pointed the lens so
the bird was in the selected display area.

The camera will not autofocus on insects - for that I will need to read
the documentation, which, knowing me I may never do.

Ron O

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May 19, 2013, 6:49:40 AM5/19/13
to
On May 17, 11:45�am, Friar Broccoli <elia...@gmail.com> wrote:
> Near my home are Cambrian sedimentary rocks.
>
> Yesterday I noticed a distinct layer with overlapping segments. �At
> first I thought it was a unique anomalous feature, but then (about 50
> vertical feet up - 300 feet farther along/downstream) I saw another
> layer that had been laid down at a later time with exactly the same
> overlapping characteristics.
>
> (There is a third, less distinct, layer between the two shown)
>
> Here are photos of the two locations:
>
> https://picasaweb.google.com/107817774238317597615/Temp_images?noredi...
>
> or
>
> http://goo.gl/qK0Fp
>
> Can anyone suggest how these overlaps might have formed? �I have no
> clue.
>
> --
> � Friar Broccoli (Robert Keith Elias), Quebec Canada
> � �I consider ALL arguments in support of my views

It looks like you've discovered rocks evolving sexual reproduction.
Just one more way to account for all those pesky layers of rock
supposedly put down by the flood.

Ron Okimoto

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