earthquakes and the san andreas fault

8/7/2019 EARTHQUAKES AND THE SAN ANDREAS FAULT

1/32

1And Jesus went out, and departed from the temple: and his disciples came tohim for to shew him the buildings of the temple.

2And Jesus said unto them, See ye not all these things? verily I say unto you,There shall not be left here one stone upon another, that shall not be thrown

down.

3And as he sat upon the mount of Olives, the disciples came unto himprivately, saying, Tell us, when shall these things be? and what shall be the signof thy coming, and of the end of the world?

4And Jesus answered and said unto them, Take heed that no man deceive you.5For many shall come in my name, saying, I am Christ; and shall deceive many.

6And ye shall hear of wars and rumours of wars: see that ye be not troubled:for all these things must come to pass, but the end is not yet.

7For nation shall rise against nation, and kingdom against kingdom: and thereshall be famines, and pestilences, and earthquakes, in divers places.

8All these are the beginning of sorrows.


2/32

David K. Lynch, PhD, geology.com

QUOTE : ......The San Andreas Fault is the sliding boundarybetween the Pacific Plate and the North American Plate. It slices

California in two from Cape Mendocino to the Mexican border.San Diego, Los Angeles and Big Sur are on the Pacific Plate. SanFrancisco, Sacramento and the Sierra Nevada are on the NorthAmerican Plate. And despite San Franciscos legendary 1906earthquake, the San Andreas Fault does not go through the city.

But communities like Desert Hot Springs, San Bernardino,Wrightwood, Palmdale, Gorman, Frazier Park, Daly City. PointReyes Station and Bodega Bay lie squarely on the fault and aresitting ducks. ......UNQUOTE.

http://geology.com/articles/san-andreas-fault.shtml


3/32

David K. Lynch, PhD, geology.com :

QUOTE : .... The hallmark of the San Andreas Fault is the different rockson either side of it. Being about 28 million years old, rock from greatdistances have been juxtaposed against rocks from very differentlocations and origins. The Salinian block of granite in central andnorthern California originated in Southern California, and some even saynorthern Mexico. Pinnacles National Monument in Monterey County isonly half of a volcanic complex, the other part being 200 miles southeastin Los Angeles County and is known as the Neenach Volcanics.

There are many myths and legends about the San Andreas Fault, thebiggest being that it will one day crack and California will slide into the

sea. WRONG! It wont happen and it cant happen. Nor is there any thingsuch as earthquake weather or preferred times of day whenearthquakes hit......UNQUOTE.

http://geology.com/articles/san-andreas-fault.shtml


4/32

Sandra S. Schulz and Robert E. Wallace ,USGS :

QUOTE: .... The presence of the San Andreas fault was

brought dramatically to world attention on April 18,1906, when sudden displacement along the faultproduced the great San Francisco earthquake and fire.This earthquake, however, was but one of many thathave resulted from episodic displacement along thefault throughout its life of about 15-20 millionyears......UNQUOTE.

http://pubs.usgs.gov/gip/earthq3/safaultgip.html


5/32


QUOTE : .... Scientists have learned that the Earth's crust is fracturedinto a series of "plates" that have been moving very slowly over theEarth's surface for millions of years. Two of these moving plates meet inwestern California; the boundary between them is the San Andreas fault.The Pacific Plate (on the west) moves northwestward relative to theNorth American Plate (on the east), causing earthquakes along the fault.The San Andreas is the "master" fault of an intricate fault network thatcuts through rocks of the California coastal region. The entire SanAndreas fault system is more than 800 miles long and extends to depthsof at least 10 miles within the Earth. In detail, the fault is a complex zoneof crushed and broken rock from a few hundred feet to a mile wide.

Many smaller faults branch from and join the San Andreas fault zone.Almost any road cut in the zone shows a myriad of small fractures, faultgouge (pulverized rock), and a few solid pieces of rock......UNQUOTE.



6/32


QUOTE : .... Along the Earth's plate boundaries, such as the San Andreasfault, segments exist where no large earthquakes have occurred for long

intervals of time. Scientists term these segments "seismic gaps" and, ingeneral, have been successful in forecasting the time when some of theseismic gaps will produce large earthquakes. Geologic studies show thatover the past 1,400 to 1,500 years large earthquakes have occurred atabout 150-year intervals on the southern San Andreas fault. As the lastlarge earthquake on the southern San Andreas occurred in 1857, thatsection of the fault is considered a likely location for an earthquake withinthe next few decades. The San Francisco Bay area has a slightly lower

potential for a great earthquake, as less than 100 years have passed sincethe great 1906 earthquake; however, moderate-sized, potentiallydamaging earthquakes could occur in this area at any time......UNQUOTE.



7/32


QUOTE: ...A great earthquake very possibly will not occur unannounced. Such anearthquake may be preceded by an increase in seismicity for several years, possiblyincluding several foreshocks of about magnitude 5 along the fault. Before the next

large earthquake, seismologists also expect to record changes in the Earth's surface,such as a shortening of survey lines across the fault, changes in elevation, andeffects on strainmeters in wells. A key area for research on methods of earthquakeprediction is the section of the San Andreas fault near Parkfield in centralCalifornia, where a moderate-size earthquake has occurred on the average of every20-22 years for about the last 100 years. Since the last sizeable earthquake occurredin 1966, Parkfield has a high probability for a magnitude 5-6 earthquake before theend of this century and possibly one may occur within a few years of 1988. TheU.S. Geological Survey has placed an array of instruments in the Parkfield area and

is carefully studying the data being collected, attempting to learn what changesmight precede an earthquake of about that size..... .UNQUOTE.



8/32


QUOTE: ... A major program aimed at learninghow to predict earthquakes and to assess and

minimize their hazards was initiated following theEarthquake Hazards Reduction Act of 1977 and isbeing carried out by the U.S. Geological Survey,other Federal Agencies, universities, and private

groups......UNQUOTE.



9/32

QUOTE: .... The Congress finds and declares the following : (1) All 50 States are vulnerable to the hazards of earthquakes, and at least 39 of

them are subject to major or moderate seismic risk, including Alaska, California,Hawaii, Illinois, Massachusetts, Missouri, Montana, Nevada, New Jersey, NewYork, South Carolina, Utah, and Washington. A large portion of the population ofthe United States lives in areas vulnerable to earthquake hazards.(2) Earthquakes have caused, and can cause in the future, enormous loss of life,

injury, destruction of property, and economic and social disruption. With respect tofuture earthquakes, such loss, destruction, and disruption can be substantiallyreduced through the development and implementation of earthquake hazardsreduction measures, including (A) improved design and construction methods andpractices, (B) land-use controls and redevelopment, (C) prediction techniques andearly-warning systems, (D) coordinated emergency preparedness plans, and (E)public education and involvement programs.

(3) An expertly staffed and adequately financed earthquake hazards reductionprograms, based on Federal, State, local, and private research, planning,decisionmaking, and contributions would reduce the risk of such loss, destruction,and disruption in seismic areas by an amount far greater than the cost of suchprogram.......UNQUOTE.



10/32

QUOTE : ... Before the 1964 Alaska earthquake, there was littleawareness of the earthquake hazard in the United States. A $2million proposal to study the San Andreas Fault Zone in the early1960's got nowhere. However, some important earthquakeresearch and publications were done by several USGS authors

beginning in the late 1880s. After the 1964 Alaska earthquake, manyUSGS scientistsparticipated in investigations, and the USGS produced 30+ articlesinUSGS series and outside journals. Two types of reports wereproduced - those that reported on the earthquake itself, and thosethat recommended federal responses to potential futureearthquakes. TheU.S. Coast and Geodetic Survey, which was to

eventually become the USGS, produced a report on theearthquake also, which led to follow-up proposals, whicheventually led to the National Earthquake Hazards Reduction(NEHR) Act of 1977....UNQUOTE.

http://earthquake.usgs.gov/aboutus/history.php


11/32

QUOTE :.... in 1977 the National Earthquake Hazard Reduction Act waspassed, and now an implementation plan had to be written, which wascompleted in 1978, and the NEHRP was finally underway. After eachmajor urban earthquake, big policy changes still take place.

During the 1950s, the USGS participated in a program using the seismicsignals from underground explosions, Soviet nuclear tests, to learn of the

Earth's crust. This knowledge was important in the interpretation of theunderground explosion signals. This successful project was phased outand the study of natural seismic events, earthquakes, was phased in. TheDenver group involved in the previous project moved to Menlo Park, CA,a location in a state with plentiful earthquakes, where the National Centerfor Earthquake Research began. The name was changed to the Office ofEarthquake Studies, and currently, the National Earthquake HazardsProgram.

TheUSGS Earthquake Hazard Program is funded by the NEHRP moneyand also from other sources. NEHRP began with about $60-70 millioneach year (and inflation has slowly eaten away at it), about half of thatgoing to theUSGS......UNQUOTE.

http://earthquake.usgs.gov/aboutus/history.php


12/32

By Katharine Gammon ,30TH March,2011, Our Amazing Planet :

... New data from a deep borehole that crosses the San Andreas Faultshows that the monster earthquake-maker has a soft center and it'smade of clay. This is the first time researchers have been able to rule outother reasons for the San Andreas' unusual behavior in part of California.

At the north and south, the San Andreas Fault is locked up prone toearthquakes near San Francisco and Los Angeles. However, nearParkfield, Calif., about 200 miles northwest of Los Angeles, the fault iscreeping, or moving slowly.

"This is a special part of the San Andreas Fault," said U.S. GeologicalSurvey scientist David Lockner, an author of a new study on the fault. "Itseems weak enough that it slides slowly and continuously, rather than in

a jerky motion.....UNQUOTE.

http://www.ouramazingplanet.com/san-andreas-fault-weakness-found-clays-1311/


13/32

By Katharine Gammon ,30TH March,2011, Our Amazing Planet :

QUOTE : .... The stuff the researchers brought up from below the groundconfirmed that the area was indeed a weak spot in the fault.

Lockner said that there are many mechanisms that can cause weakness frompore fluid pressure that lubricates rock to frictional heating (the warming thatoccurs when material rubs together) to slippery materials. The reason for weakness

on this part of the San Andreas? Weak clays, especially a magnesium-rich claymineral called saponite.

Using the clays they found in the San Andreas, the researchers were able to re-create in the lab the constant sliding that goes on in the weak part of the fault.

Lockner said this new research, detailed online March 23 in the journal Nature, isjust part of a large, international effort to better understand the mechanisms thatcause earthquakes.

"This is one part of a broad effort to understand the properties of the San Andreassystem. While we're concentrating on the lab measurements, there are othersworking on field measurements," he said. All of the information will helpseismologists better grasp what is controlling earthquakes, from the inside out.....UNQUOTE.

http://www.ouramazingplanet.com/san-andreas-fault-weakness-found-clays-1311/


14/32

LiveScience Staff Date: 09 March 2010 Time: 05:15 AM ET

QUOTE : .... Earth has been more seismologically active in thepast 15 years or so, says Stephen S. Gao, a geophysicist at MissouriUniversity of Science & Technology. Not all seismologist agree,however.

.... San Francisco is moving toward Los Angeles at the rate ofabout 2 inches per year the same pace as the growth of yourfingernails as the two sides of the San Andreas fault slip past

one another. The cities will meet in several million years.However, this north-south movement also means that despitefears, California won't fall into the sea...... UNQUOTE.

http://www.livescience.com/6187-13-crazy-earthquake-facts.html


15/32

LiveScience Staff Date: 09 March 2010 Time: 05:15 AM ET

QUOTE :... There are about 500,000 earthquakes a year around theworld, as detected by sensitive instruments. About 100,000 of those can be

felt, and 100 or so cause damage each year. Each year the southernCalifornia area alone experiences about 10,000 earthquakes, most of themnot felt by people.

... The sun and moon cause tremors. It's long been known that theycreate tides in the planet's crust, very minor versions of ocean tides. Nowresearchers say the tug of the sun and moon on the San Andreas Faultstimulates tremors deep underground.

... A city in Chile moved 10 feet in the massive 8.8 magnitude earthquakeFeb. 27, 2010. The rip in Earth's crust shifted the city of Concepcin thatmuch to the west. The quake is also thought to have changed the planet'srotation slightly and shortened Earth's day........UNQUOTE.



16/32

QUOTE : ... Earth's bulge was trimmed a little by the 2004 Indonesianearthquake, the 9.0+ temblor that generated the deadly tsunami on Dec. 26 thatyear. Earth's midsection bulges in relation to the measurement from pole-to-pole,and the catastrophic land displacement caused a small reduction in the bulge,

making the planet more round. ... The Pacific Ring of Fire is the most geologically active region of Earth. It circles

the Pacific Ocean, touching the coasts North and South America, Japan, China andRussia. It's where the majority of Earth's major quakes occur as major plateboundaries collide.

... Oil extraction can cause minor earthquakes. These are not the quakes you readabout. Rather, because oil generally is found in soft and squishy sediment, when

oil is removed other rock moves in to fill the void, creating "mini-seismic events"that are not noticeable to humans.

....The largest earthquake ever recorded was a magnitude 9.5 in Chile on May 22,1960.



17/32

QUOTE : ..... ScienceDaily (Nov. 9, 2007) The Yellowstone"supervolcano" rose at a record rate since mid-2004, likely because a LosAngeles-sized, pancake-shaped blob of molten rock was injected 6 milesbeneath the slumbering giant, University of Utah scientists report in thejournal Science.

"There is no evidence of an imminent volcanic eruption or hydrothermal

explosion. That's the bottom line," says seismologist Robert B. Smith, leadauthor of the study and professor of geophysics at the University of Utah."A lot of calderas [giant volcanic craters] worldwide go up and downover decades without erupting."

The upward movement of the Yellowstone caldera floor -- almost 3 inches(7 centimeters) per year for the past three years -- is more than three timesgreater than ever observed since such measurements began in 1923, says

the study in the Nov. 9 issue of Science by Smith, geophysics postdoctoralassociate Wu-Lung Chang and colleagues......UNQUOTE.

http://www.sciencedaily.com/releases/2007/11/071108141612.htm


18/32

QUOTE :... October 1, 2007 Seismologists investigatingundersea earthquakes have found that molten rocklubricates faults. This decreases the amount of frictionbetween sides of the fault and decreases the intensity ofearthquakes. They also found that the fragmentation of fault

lines along the seafloor contributes an earthquake-dampening effect...In December 2004, an underwater earthquake triggered a string

of tsunamis along the Indian Ocean with devastating effects.Now, scientists have found ways nature is preventing somedeep ocean earthquakes and save lives. Strong underwater

earthquakes start off silent -- until their tsunami waves roaron shore, destroying property and lives..... UNQUOTE.

http://www.sciencedaily.com/videos/2007/1007-underwater_earthquakes.htm


19/32

QUOTE : .... Molten rock -- or magma -- from under-sea volcanoes lubricates thefault, reducing the amount of friction that could cause another earthquake. Byanalyzing data collected by sea vessels, they discovered volcanic activity may beweakening fault lines. The hot rock could be serving as a geological lubricant,making the fault line more malleable. Less friction means less of a quake. "So, thescale of the earthquake is smaller because the volcanism warms up the fault lineand makes it more difficult to break rocks," Gregg says.

"Our ultimate purpose is to forecast earthquakes on land because earthquakescause so much damage and kill so many people," says Jian Lin, Ph.D., seniorscientist in the Department of Geology & Geophysics at Woods HoleOceanographic Institution.

By understanding what happens below the Earth's surface, geophysicists are

hoping to be able to send a warning to those above-ground. The researchers say itis easier to study fault lines below sea level. They are simple in their geology andhistory. Fault lines on land have layers of history that make it harder to understandthe physics of how they began....UNQUOTE.

http://www.sciencedaily.com/videos/2007/1007-underwater_earthquakes.htm


20/32

QUOTE : .... ScienceDaily (Dec. 7, 2009) Most earthquakesoccur along fault lines, which form boundaries between twotectonic plates. As the relative speed of the plates around a faultincreases, is there a corresponding increase in the number ofearthquakes produced along the fault? According to this studypublished in the December issue of BSSA, the answer dependsupon the type of tectonic boundary. On certain types of boundary,the efficiency of earthquake production actually depends on thefault slip rate...... Seismic hazard assessments consider many factors, includingrelative plate velocity. It is important to understand whether thereis a linear relationship between relative plate velocity along a fault

and the production of earthquakes in order to estimate risk topopulations and manmade structures from seismic activity. ...UNQUOTE.



21/32

QUOTE : ... 31 December 2004by Richard Conan-Davies

So what was happening to cause that massive tsunami that has causedso much damage and loss of life?

It was an undersea earthquake that measured 9.0 on the richter scalewhich makes it the 4th largest earthquake to be recorded.

The size of the area that actually shook had maximum length of 1200 --1300 km parallel to the Sunda trench and a width of over 100 km . Thefault line was estimated to have move some.

Dr Cvetan Sinadinovski, Duty Seismologist with Geoscience Australiaexplained that "This is the largest earthquake in the world for fortyyears, and the fifth largest in the world since 1900,"

Earthquakes this large tend to cause tiny changes in the Earth's rotationby change in length of day: -2.676 microseconds which is not reallymeasurable.

This earthquake is also described as a megathrust earthquake becauseit is the result of one of earth's tectonic plates sliding under another.This builds up pressure over along time but eventually the pressure istoo great for the rock and the whole fault line shifts......UNQUOTE.


22/32

QUOTE : ... ScienceDaily (Feb. 12, 2005) EVANSTON, Ill. ---NorthwesternUniversity seismologists have determined that the Dec. 26Sumatra earthquake that set off a deadly tsunami throughout the IndianOcean was three times larger than originally thought, making it thesecond largest earthquake ever instrumentally recorded and explainingwhy the tsunami was so destructive...

By analyzing seismograms from the earthquake, Seth Stein and EmileOkal, both professors of geological sciences in Northwestern's WeinbergCollege of Arts and Sciences, calculated that the earthquake's magnitudemeasured 9.3, not 9.0, and thus was three times larger. These results haveimplications for why Sri Lanka suffered such a great impact and alsoindicate that the chances of similar large tsumanis occurring in the samearea are reduced.

"The rupture zone was much larger than previously thought," said Stein."The initial calculations that it was a 9.0 earthquake did not take intoaccount what we call slow slip, where the fault, delineated by aftershocks,shifted more slowly. The additional energy released by slow slip alongthe 1,200-kilometer long fault played a key role in generating thedevastating tsunami......UNQUOTE.



23/32

QUOTE : ..... ScienceDaily (Jan. 12, 2010) The January 12, 2010, Haitiearthquake occurred in the boundary region separating the Caribbeanplate and the North America plate. This plate boundary is dominated byleft-lateral strike slip motion and compression, and accommodates about20 mm/y slip, with the Caribbean plate moving eastward with respect tothe North America plate.

Haiti occupies the western part of the island of Hispaniola, one of theGreater Antilles islands, situated between Puerto Rico and Cuba. At thelongitude of the January 12 earthquake, motion between the Caribbeanand North American plates is partitioned between two major east-westtrending, strike-slip fault systems -- the Septentrional fault system innorthern Haiti and the Enriquillo-Plantain Garden fault system insouthern Haiti.

The location and focal mechanism of the earthquake are consistent withthe event having occurred as left-lateral strike slip faulting on theEnriquillo-Plantain Garden fault system. This fault system accommodatesabout 7 mm/y, nearly half the overall motion between the Caribbeanplate and North America plate.....UNQUOTE .



24/32

QUOTE : .... ScienceDaily (Mar. 15, 2011) The magnitude 9.0earthquake that struck Japan March 11, 2011 may have slightlyshortened the length of each Earth day and shifted its axis.

...Using a United States Geological Survey estimate for how thefault responsible for the earthquake slipped, research scientist

Richard Gross of NASA's Jet Propulsion Laboratory, Pasadena,Calif., applied a complex model to perform a preliminarytheoretical calculation of how the Japan earthquake -- the fifthlargest since 1900 -- affected Earth's rotation. His calculationsindicate that by changing the distribution of Earth's mass, theJapanese earthquake should have caused Earth to rotate a bitfaster, shortening the length of the day by about 1.8 microseconds

(a microsecond is one millionth of a second).....UNQUOTE.



25/32

QUOTE :.... The calculations also show the Japan quake should haveshifted the position of Earth's figure axis (the axis about which Earth'smass is balanced) by about 17 centimeters (6.5 inches), towards 133degrees east longitude. Earth's figure axis should not be confused with itsnorth-south axis; they are offset by about 10 meters (about 33 feet). Thisshift in Earth's figure axis will cause Earth to wobble a bit differently as it

rotates, but it will not cause a shift of Earth's axis in space -- only externalforces such as the gravitational attraction of the sun, moon and planetscan do that.

Both calculations will likely change as data on the quake are furtherrefined.

In comparison, following last year's magnitude 8.8 earthquake in Chile,Gross estimated the Chile quake should have shortened the length of day

by about 1.26 microseconds and shifted Earth's figure axis by about 8centimeters (3 inches). A similar calculation performed after the 2004magnitude 9.1 Sumatran earthquake revealed it should have shortenedthe length of day by 6.8 microseconds and shifted Earth's figure axis byabout 7 centimeters, or 2.76 inches. How an individual earthquake affectsEarth's rotation depends on its size (magnitude), location and the detailsof how the fault slipped......



26/32

QUOTE : .... ScienceDaily (Feb. 10, 2011) A chronology of 1,000 yearsof earthquakes at the southern end of the San Andreas Fault nixes theidea that lake changes in the now-dry region caused past quakes.However, researchers say, the timeline pulled from sediment in threedeep trenches confirms that this portion of the fault is long past theexpected time for a major temblor that would strongly shake the Los

Angeles Basin. The new study, appearing in the February issue of the Bulletin of the

Seismological Society ofAmerica, doesn't change existing thinking about thethreat of a major quake -- potentially measuring 7.0 to 8.0 on the Richterscale -- for southern California. It does, however, provide the firstpublished documentation of much-discussed data that have emerged inthe last three decades from an area that is now rapidly being built up andpopulated, just north of the Salton Sea

Projections of such a quake in recent years led to the nation's largest-everdrill, the Great Southern California ShakeOut, last year. The 2011ShakeOut is set for Oct. 20. There's even a video projection of the quake'sprobable route created by the Southern California Earthquake Center. Thelast earthquake to originate from the area occurred in about 1690......UNQUOTE.



27/32

QUOTE : ...The new study, appearing in the February issue of the Bulletin of the SeismologicalSociety ofAmerica, doesn't change existing thinking about the threat of a major quake --potentially measuring 7.0 to 8.0 on the Richter scale -- for southern California. It does, however,provide the first published documentation of much-discussed data that have emerged in thelast three decades from an area that is now rapidly being built up and populated, just north ofthe Salton Sea.

Projections of such a quake in recent years led to the nation's largest-ever drill, the GreatSouthern California ShakeOut, last year. The 2011 ShakeOut is set for Oct. 20. There's even a

video projection of the quake's probable route created by the Southern California EarthquakeCenter. The last earthquake to originate from the area occurred in about 1690. The new study, said co-author Ray Weldon, professor and head of the department of

geological sciences at the University of Oregon, documents that the south end of the SanAndreas fault has gone perhaps 140 years longer than the average 180 years between quakes.

"We have dated the last five to seven prehistoric earthquakes of the southernmost 100kilometers (about 60 miles) of the San Andreas Fault, which is the only piece of the fault thathasn't ruptured in historical times," Weldon said. "If you were there in about 1690, when thelast earthquake occurred, the odds of getting to 2010 without an earthquake would have been

20 percent or less." Weldon stopped short of concluding that a major earthquake is due or overdue, saying that

data from this study and other recent work may just as well point to unknowns in currentearthquake-modeling techniques.

The seven earthquake events, including the two possible temblors, were placed between 905-961 AD, 959-1015 (possible), 1090-1152, 1275-1347, 1320-1489 (possible), 1588-1662 and 1657-1713, based on analyses of seismic structures preserved in the sediment in the three trenchesand 82 radiocarbon dates drawn from 61 samples of organic material...... UNQUOTE.



28/32

QUOTE : ... Weldon and co-authors -- formerUO graduatestudent Belle Philibosian, now pursuing a doctorate at theCalifornia Institute of Technology (Cal Tech), and Thomas Fumalof the U.S. Geological Survey, who died in December -- concludedthere is a high probability of rupture in the fault because of alikely buildup of tectonic stress.

The study area is in the dry bed of prehistoric Lake Cahuilla atCoachella, Calif. The lake has been dry since about 1715, accordingto timelines found in early travelers' descriptions of the area.Researchers found that the lakebed was full of water six times inthe study period.

"We now have the best chronology of these lakes that has ever

existed," said Weldon, who knows the area well from previouswork.



29/32

QUOTE : .... earthquakes have at times shifted the Colorado River'spathway into or away from Lake Cahuilla's bed, perhaps by shakendriven lateral spreading and collapse of its riverbanks

Seismic activity has been common in the Imperial Valley south of theSalton Sea, which is the continuation of the plate boundary to the southbut not part of the actual fault, Weldon noted.

"At some point, this area will get kicked by shaking from one of the manyquakes that happen south of the San Andreas Fault," he said. "It willrupture northward along the fault. When it comes into the SanBernardino Valley, seismic energy will be directed by a series of basins,including the Los Angeles Basin, into the most highly populated part ofSouthern California."

TheU.S. Geological Survey supported the research. A National Science

Foundation Graduate Research Fellowship also supported Philibosian,who was the study's lead author.....UNQUOTE.



30/32

June 3, 2010 A new catalog of earthquake locations and focalmechanisms for the California Central Coast underscores the faultcomplexity of the region and identifies newly observed features offshorenear San ...

The Central Coast is bounded on the east by the San Andreas Fault, themajor plate boundary fault, and lies between the greater San Francisco

and Los Angeles areas. This coastal region is not as densely instrumentedor as tectonically well understood as the San Andreas Fault or the majorurban areas.

The identification of new faults, and the reinterpretation of known faults,suggests that further work is necessary to better constrain the seismichazards of the Central Coast. While the locations and focal mechanisms(the direction of slip in an earthquake and the orientation of the fault on

which it occurs) for aftershocks of the 2003 M6.5 San Simeon and 2004M6.0 Parkfield earthquakes are similar to those found in previousaftershock studies, the seismicity features in the offshore region near SanLuis Obispo are sharpened considerably by this study......UNQUOTE.



31/32

QUOTE : ... The most prominent newly-observed feature is the ShorelineFault, a ~25 km-long vertical strike-slip fault running parallel to thecoastline just offshore of Point Buchon. Several smaller strike-slipseismicity lineations are also observed in Estero Bay, along with a deepreverse structure at the depth of the top of the remnant subducted slab.Strike-slip faulting is observed along the Hosgri-San Simeon Fault

system, up to ~10-15 km inland from the Hosgri Fault in Estero Bay andnear Point Buchon, and on the onshore Rinconada and West HuasnaFaults.

The Shoreline Fault in particular requires further study to better constrainits geometry, how it may connect to the Hosgri Fault or other faults to itseast, its slip rate and whether it has produced large earthquakes in thepast.

This research was recently published in theBu

lletin of theS

eismologicalSociety ofAmerica (BSSA).....UNQUOTE.



32/32

QUOTE : ....And Jesus went out, and departed from the temple: and hisdisciples came to him for to shew him the buildings of the temple.

2And Jesus said unto them, See ye not all these things? verily I say untoyou, There shall not be left here one stone upon another, that shall not be

thrown down.

3And as he sat upon the mount of Olives, the disciples came unto himprivately, saying, Tell us, when shall these things be? and what shall bethe sign of thy coming, and of the end of the world?

4And Jesus answered and said unto them, Take heed that no man deceiveyou.

5For many shall come in my name, saying, I am Christ; and shall deceive

many.

6And ye shall hear of wars and rumours of wars: see that ye be nottroubled: for all these things must come to pass, but the end is not yet.

7For nation shall rise against nation, and kingdom against kingdom: andthere shall be famines, and pestilences, and earthquakes, in divers places.

8All these are the beginning of sorrows.......UNQUOTE.

earthquakes and the san andreas fault

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