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Download Gta San Andreas Additional File \/\/FREE\\\\

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Jan 25, 2024, 7:19:38 PMJan 25
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<div>I hope this workflow helps you as much as it helped me and several people i showed it too - If you want please tweet this article. And also feel free to hit me up on twitter if you have any further questions or suggestions how to improve my workflow: andreasklinger</div><div></div><div></div><div>The San Andreas Faultby Sandra S. Schulz and Robert E. Wallace</div><div></div><div></div><div></div><div> The presence of the San Andreas fault was broughtdramatically to world attention on April 18, 1906, when suddendisplacement along the fault produced the great San Franciscoearthquake and fire. This earthquake, however, was but one ofmany that have resulted from episodic displacement along thefault throughout its life of about 15-20 million years. What Is It? Scientists have learned that the Earth's crust is fracturedinto a series of "plates" that have been moving very slowly overthe Earth's surface for millions of years. Two of these moving plates meet in western California; theboundary between them is the San Andreas fault. The PacificPlate (on the west) moves northwestward relative to the NorthAmerican Plate (on the east), causing earthquakes along thefault. The San Andreas is the "master" fault of an intricatefault network that cuts through rocks of the California coastalregion. The entire San Andreas fault system is more than 800miles long and extends to depths of at least 10 miles within theEarth. In detail, the fault is a complex zone of crushed andbroken rock from a few hundred feet to a mile wide. Many smallerfaults branch from and join the San Andreas fault zone. Almostany road cut in the zone shows a myriad of small fractures, faultgouge (pulverized rock), and a few solid pieces of rock.Where Is It? The San Andreas fault forms a continuous narrow break in theEarth's crust that extends from northern California southward toCajon Pass near San Bernardino. Southeastward from Cajon Passseveral branching faults, including the San Jacinto and Banningfaults, share the movement of the crustal plates. In thisstretch of the fault zone, the name "San Andreas" generally is applied to the northeastern most branch.What Surface Features Characterize It? Over much of its length, a linear trough reveals thepresence of the San Andreas fault; from the air, the lineararrangement of lakes, bays, and valleys in this trough isstriking. Viewed from the ground, however, the features are moresubtle. For example, many people driving near Crystal SpringsReservoir, near San Francisco, or along Tomales Bay, or throughCajon or Tejon Passes may not realize that they are within theSan Andreas fault zone. On the ground, the fault can berecognized by carefully inspecting the landscape. The fault zoneis marked by distinctive landforms that include long straightescarpments, narrow ridges, and small undrained ponds formed bythe settling of small blocks within the zone. Many streamchannels characteristically jog sharply to the right where theycross the fault.What Kind of Movement Has Occurred Along theFault? Blocks on opposite sides of the San Andreas fault movehorizontally. If a person stood on one side of the fault andlooked across it, the block on the opposite side would appear tohave moved to the right. Geologists refer to this type faultdisplacement as right-lateral strike-slip. During the 1906 earthquake in the San Francisco region,roads, fences, and rows of trees and bushes that crossed thefault were offset several yards, and the road across the head ofTomales Bay was offset almost 21 feet, the maximum offsetrecorded. In each case, the ground west of the fault movedrelatively northward. Sudden offset that initiates a great earthquake occurs ononly one section of the fault at a time. Total offsetaccumulates through time in an uneven fashion, primarily bymovement on first one, and then another section of the fault. The sections that produce great earthquakes remain "locked" andquiet over a hundred or more years while strain builds up; then,in great lurches, the strain is released, producing greatearthquakes. Other stretches of the fault, however, apparentlyaccommodate movement more by constant creep than by suddenoffsets that generate great earthquakes. In historical times,these creeping sections have not generated earthquakes of themagnitude seen on the "locked" sections. Geologists believe that the total accumulated displacementfrom earthquakes and creep is at least 350 miles along the SanAndreas fault since it came into being about 15-20 million yearsago. Studies of a segment of the fault between Tejon Pass andthe Salton Sea revealed geologically similar terranes on oppositesides of the fault now separated by 150 miles, and some crustalblocks may have moved through more than 20 degrees oflatitude. Although it is difficult to imagine this great amount ofshifting of the Earth's crust, the rate represented by theseancient offsets is consistent with the rate measured inhistorical time. Surveying shows a drift at the rate of as muchas 2 inches per year.What Is an Earthquake? The crustal plates of the Earth are being deformed bystresses from deep within the Earth. The ground first bends,then, upon reaching a certain limit, breaks and "snaps" to a newposition. In the process of breaking or "faulting," vibrationsare set up that are the earthquakes. Some of the vibrations areof very low frequency, with many seconds between waves, whereasother vibrations are of high enough frequency to be in theaudible range. The vibrations are of two basic types, compression waves andtransverse or shear waves. Since the compression waves travelfaster through the Earth, they arrive first at a distant point;they are known as primary or "P" waves. The transverse wavesarriving later are referred to as shear or "S" waves. In anearthquake, people may note first a sharp thud, or blast-likeshock, that marks the arrival of the P wave. A few secondslater, they may feel a swaying or rolling motion that marks thearrival of the S wave.What Do Earthquake "Magnitude" and "Intensity"Mean? Magnitude is a measure of the size of an earthquake. TheRichter Scale, named after Charles F. Richter of the CaliforniaInstitute of Technology, is the best known scale for themeasuring of magnitude (M) of earthquakes. The scale islogarithmic; a recording of 7, for example, signifies adisturbance with ground motion 10 times as large as a recordingof 6. The energy released by an earthquake of M 7, however, isapproximately 30 times that released by an earthquake of M 6; anearthquake of M 8 releases 900 times (30x30) the energy of anearthquake of M 6. An earthquake of magnitude 2 is the smallestearthquake normally felt by humans. Earthquakes with a Richtervalue of 5 or higher are potentially damaging. Some of theworld's largest recorded earthquakes--on January 31, 1906, offthe coast of Colombia and Ecuador, and on March 2, 1933, off theeast coast of Honshu, Japan--had magnitudes of 8.9 on this scale,which is open ended. As the Richter scale does not adequately differentiatebetween the largest earthquakes, a new "moment magnitude" scaleis being used by seismologists to provide a better measure. Onthe moment magnitude scale, the San Francisco earthquake isestimated at magnitude 7.7 compared to an estimated Richtermagnitude of 8.3. Intensity is a measure of the strength of shakingexperienced in an earthquake. The Modified Mercalli Scalerepresents the local effect or damage caused by an earthquake;the "intensity" reported at different points generally decreasesaway from the earthquake epicenter. The intensity range, from I -XII, is expressed in Roman numerals. For example, an earthquakeof intensity II barely would be felt by people favorablysituated, while intensity X would produce heavy damage,especially to unreinforced masonry. Local geologic conditionsstrongly influence the intensity of an earthquake. Commonly,sites on soft ground or alluvium have intensities 2 to 3 unitshigher than sites on bedrock.Earthquakes Along the Fault Literally thousands of small earthquakes occur in Californiaeach year, providing scientists with clear indications of placeswhere faults cut the Earth's crust. The largest historicalearthquakes that occurred along the San Andreas fault were thosein 1857 and 1906. The earthquake of January 9, 1857, in southern Californiaapparently was about the same magnitude as the San Franciscoearthquake of 1906. According to newspaper accounts, groundmovement in both cases was roughly the same type. An account ofthe 1857 earthquake describes a sheep corral cut by the faultthat was changed from a circle to an "S"-shape--movement clearlyrepresentative of right-lateral strike-slip. Studies of offsetstream channels indicate that as much as 29 feet of movementoccurred in 1857. The San Francisco earthquake and fire of April 18, 1906,took about 700 lives and caused millions of dollars worth ofdamage in California from Eureka southward to Salinas and beyond.The earthquake was felt as far away as Oregon and central Nevada.The 1906 earthquake, which has been estimated at a magnitude 8.3on the Richter Scale, caused intensities as high as XI on theModified Mercalli Scale. Surface offsets occurred along a 250-mile length of the fault from San Juan Bautista north past PointArena and offshore to Cape Mendocino. On May 18, 1940, an earthquake of magnitude 7.1 occurredalong a previously unrecognized fault in the Imperial Valley. Similar movement on the Imperial fault occurred during anearthquake in November 1979. The greatest surface displacementwas 17 feet of right-lateral strike-slip in the 1940 earthquake. Clearly, this fault is part of the San Andreas system. Otherearthquakes of probable magnitudes of 7 or larger occurred on theHayward fault in 1836 and 1868 and on the San Andreas fault in1838.When Could the Next Large Earthquake Occur Alongthe San Andreas Fault? Along the Earth's plate boundaries, such as the San Andreasfault, segments exist where no large earthquakes have occurredfor long intervals of time. Scientists term these segments"seismic gaps" and, in general, have been successful inforecasting the time when some of the seismic gaps will producelarge earthquakes. Geologic studies show that over the past1,400 to 1,500 years large earthquakes have occurred at about150-year intervals on the southern San Andreas fault. As thelast large earthquake on the southern San Andreas occurred in1857, that section of the fault is considered a likely locationfor an earthquake within the next few decades. The San FranciscoBay area has a slightly lower potential for a great earthquake,as less than 100 years have passed since the great 1906earthquake; however, moderate-sized, potentially damagingearthquakes could occur in this area at any time. A great earthquake very possibly will not occur unannounced.Such an earthquake may be preceded by an increase in seismicityfor several years, possibly including several foreshocks of aboutmagnitude 5 along the fault. Before the next large earthquake,seismologists also expect to record changes in the Earth'ssurface, such as a shortening of survey lines across the fault,changes in elevation, and effects on strainmeters in wells. Akey area for research on methods of earthquake prediction is thesection of the San Andreas fault near Parkfield in centralCalifornia, where a moderate-size earthquake has occurred on theaverage of every 20-22 years for about the last 100 years. Sincethe last sizeable earthquake occurred in 1966, Parkfield has ahigh probability for a magnitude 5-6 earthquake before the end ofthis century and possibly one may occur within a few years of1988. The U.S. Geological Survey has placed an array ofinstruments in the Parkfield area and is carefully studying thedata being collected, attempting to learn what changes mightprecede an earthquake of about that size.What Can Be Done About the Faults andEarthquakes? Even though people cannot stop earthquakes from happening,they can learn to live with the problems caused by earthquakes. Three major lines of defense against earthquake hazards are beingdeveloped. Buildings in earthquake-prone areas should bedesigned and constructed to resist earthquake shaking. Buildingcodes that require attention to earthquake shaking have beenimproving in recent decades and constitute a first line ofdefense. In some cities, programs are underway to strengthen ortear down older buildings most likely to collapse duringearthquakes. A second line of defense involves the selective useof land to minimize the effects of hazardous ground. High-occupancy or critical structures, for example, should not beplaced astride the San Andreas fault or on landslide-prone areas.The third line of defense will be the accurate prediction ofearthquakes. When such prediction becomes possible, it willpermit timely evacuation of the most hazardous buildings. Amajor program aimed at learning how to predict earthquakes and toassess and minimize their hazards was initiated following theEarthquake Hazards Reduction Act of 1977 and is being carriedout by the U.S. Geological Survey, other Federal Agencies,universities, and private groups. This publication is one of a series of general interestpublications prepared by the U.S. Geological Survey to provideinformation about the earth sciences, natural resources, and theenvironment. To obtain a catalog of additional titles in theseries "General Interest Publications of the U.S. GeologicalSurvey," write: U.S. Geological Survey</div><div></div><div> Information Services</div><div></div><div> P.O. Box 25286</div><div></div><div> Denver, CO 80225</div><div></div><div> As the Nation's principal conservation agency, theDepartment of the Interior has responsibility for most of ournationally owned public lands and natural resources. Thisincludes fostering the wisest use of our land and waterresources, protecting our fish and wildlife, preserving theenvironmental and cultural values of our national parks andhistorical places, and providing for the enjoyment of lifethrough outdoor recreation. The Department assesses our energyand mineral resources and works to assure that their developmentis in the best interests of all our people. The Department alsohas a major responsibility for American Indian reservationcommunities and for people who live in Island Territories underU.S. administration.</div><div></div><div> Accessibility FOIA Privacy Policies and Notices</div><div></div><div></div><div></div><div></div><div></div><div>download gta san andreas additional file</div><div></div><div>Download File: https://t.co/LhE0W8UC1s </div><div></div><div> dafc88bca6</div>
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