Details Title: Earthquakes USC Geol 240x Description: For Professor Dolan's Eq class at USC Total Flash Cards: 94 Created: 12/10/2006 14:16:38		New Users: To study from this flashcard set, or to create your own your own study flash cards, REGISTER HERE. Existing Users: CLICK HERE. Additional Geology Flashcards
Cards in this set: Term Wadati Benioff Zone: Definition Around 700km below the surface Term Mass Definition Density X Volume Term Basalt Definition Dark Greay or black; the typical lava of oceanic volcanoes; low viscosity; dense Term atlantic ocean Definition getting wider by 2cm a year Term polymorphic phase transformations Definition 400km olivine --> spinel 670km spinel --> perovstite Term convergent boundary volcanoes Definition erupt andesite Term Age of hawaiian emperor seamount chain Definition 45m years old Term Alfred WEgener Definition German meteorologist idea of pangea 300m years ago distribution or distinctive rocks, ancient mountain belts, fossil types, glacier paths, ancient deserts, and equatorial swamps; was not beleived because of lame driving mechanisms Term Sir harold jeffries Definition disproved the driving mechanisms Term arthur holmes Definition discovered paleogamentism; wasn't beleived until 1960's when mid-atlantic ridge data was published Term magnetic north pole Definition south of geographic north pole; in canada or greenland; reversed from 700,000-2,500,000 years ago Term age of the earth and oldest rocks Definition earth = 4.6 billion oldest rocks = 3.8billion (in greenland) Term equation of force Definition mass X acceleration Term equation and types of stress Definition force/area over which force is acting isotropic - even all around tectonic - caused by motion of the earth sheer - causes movement normal - prevents movement Term when last seismic activity occured in salt lake Definition 2000 years ago Term last major eq on southern part of san andreas fault Definition 1609 Term length of seismic lull in Los Angeles Urban Faults Definition 1000 years Term first earthquake in which the elastic rebound theory was studied Definition 1906 san fernando eq Term how much closer we are getting to pasadena each year due to the big bend Definition 5mm Term temp at which quarts gets squishy Definition 300 centigrade Term rate tsunamis travel at Definition 800km/hr Term equation of stress Definition elastic constant X strain (hooke's law) Term What Snell's Law explains Definition total internal reflection and non-linearity of seismic ray paths Term Moho Definition 30km below surface the interface between the crust and the mantle Term Continental Crust Composition and Thickness Definition quarts and feldspar 15-90km thick Term Oceanic Crust composition and density Definition iron and magnesium - basalt denser than continental Term Mantle composition Definition olivine and pyrosene Term Lithosphere depth Definition 0-100km Term asthenosphere depth Definition 100-200km Term landers eq magnitude and significance Definition 7.3 magnitude all energy went north, away from populus Term Crust depth Definition 0-35km Term Mantle Depth Definition 35-2900km Term Asthenosphere Depth Definition 100-200km Term Outer Core Depth Definition 2900-5200km Term Inner Core Depth Definition 5200-6400km Term Xerolyts Definition Chunks of rock wall that come up with magma Term Ophiolites Definition pieces of oceanic lithosphere that have been raised to land Term Carbonaceous Chondrite Definition meteorites that have never been heated past 100 degress Term Oldest Rock Definition 3.8billion years odl Term Age of the earth Definition 4.6 billion years Term Oldest mineral Definition 4.2billion Term 1940 imperial eq magnitude and significance Definition magnitude 7.0 el centro record which was the first on scale recording of how strong the ground could shake next to the epicenter Term 1 mile = ?km Definition 1.6km Term how many degrees the dip usually is from the maximum principle stress direction Definition 30 degrees (anderson's theory of faulting) Term San Andreas Fault Facts: Definition accomodates for 3.5cm or 70% North America' Compression a year Has a creeping section around teh san luis resivior created the april 18th 1906 san francisco and 1857 earthquakes Term Garlock Fault Facts: Definition one of the biggest faults in CA Created the San Gabriel and Santa Monica Mountans Term Cascadia Subduction Megathrust Zone Facts Definition 1000km long where the juan del fuca plate is subducting under the north american plate offshore of oregon and washington created teh cascade mountain range Term Puente Hills Fault Facts: Definition reaches to 3km below the surface under USC Caused the whittier narros eq in 1987 which broke 10% of the fault starts at the san gabriel mountains at about 15km Term Wasatch Fault Zone Facts: Definition Normal Faulting Stretches Across Utah Has yellowstone national park home of the 1959 hebgen lake eq Term North Anatolian Fault location and type: Definition Turkey Right-Lateral Strikeslip Term Inglewood/newport fault type and eq caused: Definition Right-lateral strikeslip cause dthe longbeach eq in 1933 Term Cascadia eq year and facts: Definition 1700 on the Cascadia subduction megathrust fault Caused a tsunami in japan 2 meters high Term p-wave movement Definition parallel to ray paths Term Sheer wave movement Definition perpendicular to ray paths - like a snake Term Raleigh wave movement Definition counter-clockwise vertical movement along ray path Term concrete buildings started to be built better (ductile) in what year?: Definition 1972 Term Mount Everest is Made of: Definition Limestone Term 1 inch = ? cm 1 km = ? miles Definition 2.5cm .6 miles Term Formula for Moment Magnitude(Mw): Definition sheer modulus (mu) X area X displacement Term How many meters of slip are in a M5, M7, M8, and M9 Eqs? Definition M5:a few cm's M7: a couple meters M8: 5-10 meters M9: 10's of meters Term Building Codes: Definition 1933: brick - for fire resistance 1940: non-ductile concrete - assumed eq resistant (no eqs to test on during this time) 1971: ductile concrete - because of san fernando eq 1994: steel non-ductile and ductile concrete buildings compse 85% of la buildings Term what is dilatency Definition a diffusion hypothesis that proved false which stated that you could predict an earthquake by listening for cracks Term Coulomb Failure Function Change Definition 3d stress changes due to tectonic loading and other eqs Term Unreinforced Masonry Definition can be built up to 70% of code through retrofit of inserting steel rebar through drilled holes on each floor and bolt the ends Term Turkey Failures: Definition Building codes not enforced Sand not washed not enough rebar built on loose sediments Term Kobe Failures Definition 6000 dead caused by soft first floors (shops, parking structures) Term Significance of Northridge and Loma Prieta Eqs Definition made people realize the need to increase the confinement around teh columns Term Turkey Eq Magnitudes Definition Mw7.5 Ms7.8 mD6.7 - used by the kandilli seismological institute in turkey Term 1692 Port Royal, Jamaica Eq Facts: Definition Liquifaction on the caribbean Plte Term Foreshocks Facts: Definition shallow eqs almost always have foreshocks is a function of increasing normal stress acting on a fault most normal fault eqs have foreshocks 10% sideslip faults have foreshocks reverse faults almost never have foreshocks Term aftershocks facts: Definition omori's law: the number of aftershocks a day varies inversely with the time since the mainshock almost all M>6 eqs have aftershocks Term Dead sea fault location and fault type Definition 3km behind jericho left lateral strike slip Term 1933 Long beach eq magnitude and significance Definition mw6.4 ruptured 15km lead to the very first building codes for eqs Term 1985 Michocan eq magnitude and significance: Definition mw8.5 showed how the meixco city basin had disasterous effects Term Magnitude Scales: Definition Richter Magnitude (Ml): exponential, measure of amplitude of ground motion; Surface Wave Magnitude (Ms): used to measure large eqs, measure of amplitude of ground motion, exponential; Seismic Moment Magnitude (MW): measures energy release, 32X increase each unit increase, 2X increase for every .2 unit increase; Japanese Magnitude scale (Mj): used in 1995 Kobe by media to overhype; Duration Magnitude (MD): based on how long the ground shakes; Term 1857 For Tejon Magnitude and Significance Definition MW7.9 last big eq in parkfield Term 1960 Chile Magnitude and Significance Definition mw9.5 biggest recorded eq in modern time Term 2004 Sumatra magnitude and significance Definition mw9.3 second biggest we have measured created a tsunami Term magnitude diameters: Definition mw3: 100m mw5: 1km mw6: 100km Term 1872 Owens Valley Eq magnitude and significance Definition m7.6 third largest eq recorded in CA Term January 23rd 1556 eq significance Definition most catastrophic eq recorded from chinese catalogue dating back to 78bc killed 830,000 Term 1857 Fort Tejon significance Definition one of the first indications of a rupture on the San Andreas Fault Term intermediate focus eqs depths Definition 70km-300km deep Term deep focus focus eqs depth Definition below 300km Term Moonquakes? Definition crust: 60km mantle: 1000km dense core: softer but not liquid Term List of most widely damaging eqs: Definition 2002 Denali 1999 Kocaeli 1995 Chi-Chi 1976 Tangshan, China 1906 San Francisco 1891 Mino-Owari, Japan Term December 8th 1912 San Juan Capistrano Magnitude and Significance Definition M7.5 Killed 40 people in a church was thought to be on the ingelwood fault but was later found to be on the San Andreas because of a bunch of pine trees that died on the fault at that same year Term Richter Scale facts: Definition created in 1933 as the first magnitude scale had physical limits on haw big and small the earthquake could be due to instrument limitations frequently called "local magnitude" because it is fairly accurate at measuring local eqs it cannot effectively measure large eqs Term San Francisco Eq 1868 Magnitude and Significance Definition M7.0 first large recorded eq in sf Term Locating Earthquakes Definition 1: locate surface rupture 2: locate area of maximum damage 3: arrival times of seismic waves 4: aftershock locations Term Core composition Definition Iron and Nickle Term radius of earth Definition 6371km Term Eastern Caliofirna Sheer Zone Facts: Definition near jashua tree has half a dozen faults 20% of north american's engery (1cm/yr) is released Term the earths motions: Definition displacement: micrometers to meters velocity: up to several meters/second acceleration: up to more than one g