In reflection seismology , a seismic attribute is a quantity extracted or derived from seismic data that can be analysed in order to enhance information that might be more subtle in a traditional seismic .... ref http www.slb.com services software geo petrel seismicseismic multitrace attributes.aspx Schlumberger Seismic Attribute Analysis ref Examples of seismic attributes can include measured time, amplitude , frequency and attenuation , in addition to combinations of these. Most seismic attributes ... papers AVO 20Analysis 20Demystified.pdf ref They can be measured along a single seismic trace or across multiple traces within a defined window. The first attributes developed were related to the 1D seismic trace complex seismic trace and included envelope amplitude, instantaneous phase, instantaneous frequency, and apparent polarity. Acoustic impedance obtained from seismic inversion can also be considered ... versus offset AVO , and spectral decomposition. A seismic attribute that can indicate the presence ... Amplitude attributes use the seismic signal amplitude as the basis for their computation. Mean amplitude ... for their computation, the variation in amplitude of a seismic reflection with varying offset ... attenuation factor or Q is a seismic attribute that can be determined from seismic reflection data for both petroleum reservoir reservoir characterisation and advanced seismic processing . Time Horizon attributes Coherence A post stack attribute that measures the continuity between seismic traces in a specified ... seismic events within each trace based on their frequency content. The application of these attributes ... domain, a bandpass filter can be applied to view the amplitudes of seismic data at any frequency or range ... an attribute. The seismic data is usually filtered at various frequency ranges in order to show ... relationship between the thickness of a rock layer and the corresponding peak frequency of its seismic ... book author1 S. Chopra author2 K.J. Marfurt title Seismic Attributes for Prospect ID and Reservoir ... more details
Seismic hazard refers to the study of expected earthquake ground motions at the earth s surface, and its ... the results of such studies are published as seismic hazard maps, which identify the relative ... hazard zoning haz e.php Natural Resources Canada page on Seismic Hazard Calculations ref With hazards thus determined, seismic risk their risks are assessed and included in such areas as building ... and determining insurance rates. The seismic hazard studies also may generate two standard measures ... seismic hazard were first formulated by C. Allin Cornell in 1968 ref http www.geoscienceworld.org cgi georef 1968056524 Cornell, C.A. 1968, Engineering seismic risk analysis, Bulletin of the Seismological ... McGuire 20PSHA 20History.pdf McGuire, R. 2008, Probabilistic seismic hazard analysis Early history .... A longer term seismic history can be obtained through paleoseismology . The results may be in the form of a ground response spectrum for use in seismic analysis . More elaborate variations on the theme ... note on seismic microzonation in the central United States, J. Earth Syst. Sci. 117, S2 ... than your neighbour on solid rock. The standard seismic hazard calculations become adjusted upwards ... In a normal seismic hazard analyses intended for the public, that of a maximum considered earthquake ... library glossary M Maximum design earthquake ref US seismic hazard maps Some maps released by the USGS ... in Metre per second squared . For parts of the US, the National Seismic Hazard Mapping Project in 2008 resulted in seismic hazard maps showing peak acceleration as a percentage of gravity with a 2 probability of exceedance in 50 years. See also C. Allin Cornell Earthquake engineering Mitigation of seismic motion Neotectonics Seismic performance Vibration control References Reflist External links U.S. Geological Survey National Seismic Hazard Maps http earthquake.usgs.gov research hazmaps The Global Seismic Hazard map http www.seismo.ethz.ch GSHAP http www.inrisk.ubc.ca Infrastructure Risk Research ... more details
Orphan date February 2009 Seismic Handler SH is an interactive analysis program for preferably continuous waveform data. It was developed at the Seismological Observatory Gr fenberg and is in use there for daily routine analysis of local and global seismic events. In original form Seismic Handler was command line based, but now an interactive version is available. Main features Reading traces from continuous data streams in Steim compressed MiniSEED files. Additionally supported formats are event data from GSE, AH and Q private format of SH files. Zoom in and out traces in time and amplitude. Application of a set of standard filters simulation filters and Butterworth filter s on broadband input traces. Reading phases on original or preprocessed traces. Determination of signal noise ratio Computation of teleseismic beam traces using array beamforming or FK algorithm, determination of slowness and back azimuth of an incoming wavefront. Location of teleseismic events using global travel time tables based on array methods or relative travel times, determination of focal depth using depth phases Location of regional and local events using LocSAT program, flexible interface provided for integration of own location programs. Integration of an own external programs e.g. map display, phase diagrams . Displaying theoretical travel times. Determination of amplitudes and magnitude mathematics magnitude s ml or mb and Ms . Saving analysis results into an output text file for further processing. Supported operating systems Sun Microsystems Solaris Operating System Solaris and Linux Additional features Rotation of 3 component seismogram s Particle motion diagrams Vespagram like trace summation Trace spectrum display External links http www.szgrf.bgr.de sh doc index.html Seismic Handler official home page SHM http www.seismic handler.org portal Seismic Handler development site http www.szgrf.bgr.de Seismological Observatory Gr fenberg SZGRF Category Science software Category Seismology ... more details
Seismic anisotropy is a term used in seismology to describe the directional dependence of seismic wavespeed in a medium rock geology rock within the Earth . Crustal Anisotropy In the Earth s crust, anisotropy may be caused by preferentially aligned joints or microcracks, by layered bedding in sedimentary formations, or by highly foliated metamorphic rocks. Crustal anisotropy resulting from aligned cracks can be used to determine the state of stress in the crust, since in many cases, cracks are preferentially aligned with their flat faces oriented in the direction of minimum compressive stress. In active tectonic areas, such as near faults and volcanoes, anisotropy can be used to look for changes in preferred orientation of cracks that may indicate a rotation of the stress field. Both seismic P waves and S waves may exhibit anisotropy. For both, the anisotropy may appear as a continuous dependence of velocity upon the direction of propagation. For S waves, it may also appear as a discrete dependence of velocity upon the direction of polarization. For a given direction of propagation in any homogeneous medium, only two polarization directions are allowed, with other polarizations decomposing trigonometrically into these two. Hence, shear waves naturally split into separate arrivals with these two polarizations in optics this is called birefringence . Crustal anisotropy is very important in the production of oil reservoirs, as the seismically fast directions can indicate preferred directions of fluid flow. In crustal geophysics, the anisotropy is usually weak this enables a simplification of the expressions for seismic velocities and reflectivities, as functions of propagation and polarization direction. In the simplest geophysically plausible case, that of linear elasticity Anisotropic homogeneous media polar anisotropy , the analysis is most conveniently done in terms of Thomsen Parameters . Mantle anisotropy In the mantle, anisotropy is normally associated with crystals ... more details
s 2nd law in this situation gives the homogeneous equation of motion for seismicwave propagation math ... gives the seismicwave equation in homogeneous media math rho ddot boldsymbol u left lambda ... S wave propagation. Taking the divergence of seismicwave equation in homogeneous media instead ...for the lowest energy electronic wavefunction in atomic physics atomic orbital for the S wave on an electrocardiogram ... Onde cisaillement impulsion 1d 30 petit.gif thumb 305px Plane shear wave Image Ondes cisaillement 2d 20 petit.gif thumb 305px Propagation of a spherical S wave in a 2d grid empirical model A type of Linear elasticity Elastic wave elastic wave , the S wave , secondary wave , or shear wave sometimes called an elastic S wave is one of the two main types of elastic body wave seismology body wave s, so named because they move through the body of an object, unlike surface wave s. The S wave moves as a shear or transverse wave , so motion is perpendicular to the direction of wave propagation S waves are like waves in a rope, as opposed to waves moving through a slinky , the P wave . The wave moves ... Image Earthquake wave shadow zone.svg thumb 150px The shadow zone of a P wave . S waves don t penetrate ... seismogram , after the compressional wave compressional primary wave, or P wave, because S waves travel slower in rock. Unlike the P wave, the S wave cannot travel through the molten outer core of the Earth ... appear in the solid inner core when a P wave strikes the boundary of molten and solid cores, called ... plane, they are classified as SV waves. When an S or P wave strikes an interface at an angle other than ... solid media, mode conversion results. If a P wave strikes an interface, four propagation modes may result reflected and transmitted P and reflected and transmitted SV. Similarly, if an SV wave strikes ... are described by the Zoeppritz equations , which in turn are solutions to the wave equation ... 2 frac partial 2 nabla times boldsymbol u partial t 2 0 math which is simply the wave equation applied ... more details
Refimprove date May 2008 main Earthquake engineering Seismic retrofitting is the modification of existing built environment structures to make them more resistant to seismology seismic activity , ground motion, or soil failure due to earthquake s. With better understanding of seismic demand on structures and with our recent experiences with large earthquakes near urban centers, the need of seismic retrofitting is well acknowledged. Prior to the introduction of built environment modern seismic codes ... and reinforcement for seismic protection. In view of the imminent problem, various research work has been carried out. Furthermore, state of the art technical guidelines for seismic assessment, retrofit ... practice of seismic retrofitting is predominantly concerned with structural improvements to reduce the seismic hazard of using the structures, it is similarly essential to reduce the hazards and losses ... as an earthquake proof structure, although seismic performance can be greatly enhanced through proper ... approach adopted in seismic retrofit rehabilitation technical guidelines such as FEMA356,ASCE SEI 41, EC8 3, NZSEE etc etc Strategies Seismic retrofit or rehabilitation strategies have been developed in the past few decades following the introduction of new seismic provisions and the availability ... 20Retrofit.pdf Moehle, J. 2000 State of Research on Seismic Retrofit ref Retrofit strategies are different ... of cross braces or new structural walls. Reduction of the seismic demand by means of supplementary .... Performance objectives In the past, seismic retrofit was primarily applied to achieve public ... exited. Under severe seismic conditions the structure may be a total economic write off, requiring ... structures of high cultural significance. Techniques Common seismic retrofitting techniques fall ... been developed in the past decade. Under the PRESS Precast Seismic Structural Systems , ref http fire.nist.gov bfrlpubs build94 art069.html 1994 Building Publications Status of the U.S. Precast Seismic ... more details
about waves in the scientific sense other uses of wave or waves Wave disambiguation File 2006 01 14 Surface waves.jpg thumb right 300px Surface wave s in water In physics , a wave is a disturbance or oscillation that travels through spacetime , accompanied by a transfer of energy . Wave motion transfers ... around almost fixed locations. Waves are described by a wave equation which sets out how ... of wave. There are two main types of waves. Mechanical wave s propagate through a medium, and the substance ... . This keeps the molecules from continuing to travel in the direction of the wave. The second type of wave, electromagnetic wave s, do not require a medium. Instead, they consist of periodic oscillations ... a vacuum . These types of waves vary in wavelength, and include radio wave s, infrared radiation , visible light , ultraviolet radiation , X ray s, and gamma ray s. A wave can be transverse wave transverse or longitudinal wave longitudinal depending on the direction of its oscillation. Transverse ... definition for the term wave is not straightforward. A vibration can be defined as a back and forth motion around a reference value. However, a vibration is not necessarily a wave. An attempt to define the necessary and sufficient characteristics that qualify a phenomenon to be called a wave results in a fuzzy border line. The term wave is often intuitively understood as referring to a transport ... as a whole. In a wave, the energy of a vibration is moving away from the source in the form of a disturbance ... for a standing wave for example, a wave on a string , where energy is moving in both directions equally ... and interaction with a target is the key to wave detection and practical applications. There are water ... wave phenomena. It may appear that the description of waves is closely related to their physical origin for each specific instance of a wave process. For example, acoustics is distinguished from optics in that sound waves are related to a mechanical rather than an electromagnetic wave transfer caused ... more details
The Wave may refer to The Wave TV special The Wave TV special , a made for TV movie based on the experiment The Wave novel The Wave novel , a 1981 young adult novel by Todd Strasser The Wave 2008 film The Wave 2008 film , a German film adapted from the novel The Wave building , a residential skyscraper on the Gold Coast, Australia The Wave, Arizona , a sandstone formation The Wave , English title of Redes film Redes , a Mexican film The Wave of Long Island , a newspaper The Wave in Vejle , a residential building complex in Vejle, Denmark The Great Wave off Kanagawa , a woodblock print by 19th century Japanese artist Hokusai The Third Wave , a 1967 high school experiment inspired by Nazism Wave audience , an occurrence at sporting events A painting by William Adolphe Bouguereau A type of caster board Radio stations The Wave 96.4 FM , in Swansea, Wales CHWV FM , in Saint John, New Brunswick CJLS FM , in Yarmouth, Nova Scotia CKWV FM , in Nanaimo, British Columbia WNWV , in Cleveland, Ohio KTWV , Smooth Jazz staton in Los Angeles CIWV FM , Canadian Smooth Jazz Station The Wave German radio , radio station of RTL Group from Berlin, Germany See also Wave disambiguation The Waves , a novel Stop Climate Chaos The Wave The Wave protest , a Climate Change protest in London and Glasgow held on the 5th December 2009 disambig de The Wave ja The wave ... more details
The term T wave may refer to In medicine T wave , a portion of the recording of a heartbeat in an electrocardiogram In physics Terahertz radiation , electromagnetic radiation in the microwave band. disambig ... more details
Orphan date October 2010 cleanup date October 2010 File WAVe.png thumb WAVe logo WAVe stands for Web Analysis of the Variome is a next generation web based bioinformatics tool for the Human Variome Project human variome research domain. Availability WAVe is available for public usage at http bioinformatics.ua.pt WAVe and enables gene centric navigation over miscellaneous resources in a modern and agile web interface. Funding WAVe is being developed for the GEN2PHEN European GEN2PHEN Project by the http bioinformatics.ua.pt UA.PT Bioinformatics and Computational Biology group at the Aveiro University University of Aveiro . Architecture WAVe is based on a lightweight integration architecture ref http issuu.com pedrolopes docs linkintegrator ref and uses Arabella web crawler ref http issuu.com pedrolopes docs arabella ref combined with a Java based data gathering engine to aggregate multiple resources in a centralized database. References Reflist External links http bioinformatics.ua.pt WAVeWAVe Categories Category Bioinformatics Bioinformatics stub ... more details
Merge from No Wave Cinema discuss Talk No Wave Merger proposal date December 2011 Multiple issues refimprove ... No Wave bgcolor crimson color white stylistic origins Punk rock br Avant garde music Avant garde ref ... of punk rock New Wave music New wave Post punk No Wave was a short lived but influential underground ... 1970s in New York City . ref name romanowski The term No Wave is in part satirical word play rejecting the commercial elements of the then popular New Wave music New Wave genre . The term originates from a 1981 show, New York New Wave , curated by artist Diego Cortez. ref Alison Pearlman, Unpackaging ... March 2010 No Wave is not a clearly definable musical genre with consistent features. Various groups ... music experimental . There are, however, some elements common to most No Wave music ... all books no wave.html No Wave , with a foreword by Weasel Walter London Black Dog Publishing, 2007 .... ref No Wave had a notable influence on noise and Industrial music industrial bands which followed ... in reference to a bunch of nihilists, I do feel fond of the No Wave people. James Chance s music actually ... No Wave inspired the Speed Trials noise rock series organized by Live Skull members in May 1983 at White ... ref Other No Wave musicians Do not add musicians here who are discussed previously in the article. In addition ... No Wave ref name WW archive cite web last Walter first Weasel title New York No Wave Archive url http nowave.pair.com no wave nycnowave index.html work New York No Wave Archive accessdate 27 January ... The Static Ut band Ut Von LMO Y Pants div col end No Wave Cinema No Wave Cinema was an underground ... to the Cinema of Transgression and work by Nick Zedd and Richard Kern . No Wave visual artists ... David Wojnarowicz div col end No Wave Afterlife In a foreword to the book No Wave , Weasel Walter ... movement known as No Wave were found in many other archetypes before and just as many afterwards, but for a few ... hot focus. ref name Masters Masters, Marc. 2007 No Wave London, UK Black Dog Publishing ref blockquote ... more details
cleanup linkrot date August 2011 Infobox album See Wikipedia WikiProject Albums Name Wave on Wave Type studio Longtype Artist Pat Green Cover Pat Green Wave on Wave.jpg Released Start date 2003 07 15 Recorded 2002 3 at Pedernales Studio, Spicewood, Texas Wave on Wave recorded at Cartee Day Studio, Nashville, Tennessee ref name Wave Genre Country music Country Length 54 02 Label Universal Records Universal ... , Don Gehman , Doug Morris Last album Three Days album Three Days br 2001 This album Wave on Wave br 2003 Next album Lucky Ones Pat Green album Lucky Ones br 2004 Misc Singles Name Wave on Wave Type studio Single 1 Wave on Wave song Wave on Wave Single 1 date May 26, 2003 Single 2 Guy Like Me Single ... class album id r649332 pure url yes title Wave on Wave review last Jurek first Thom work Allmusic accessdate July 4, 2011 ref noprose yes Wave on Wave is the seventh studio album released by American ... charting single, peaking at No. 3 on the country charts, while A Guy Like Me reached No. 31. Wave on Wave ... guitar line from Wave on Wave closely resembles the guitar line from Mike and the Mechanics The Living ... Wilkins length2 4 03 title3 Wrapped writer3 Green, Wilkins length3 3 28 title4 Wave on Wave song Wave on Wave writer4 Green, Neuhauser, Justin Pollard length4 4 04 title5 California writer5 Green length5 ... As listed in liner notes. ref name Wave cite album notes title Wave on Wave bandname Pat Green year ... guitar Special guest appearances John Carroll electric guitar on Elvis Chad Cromwell drums on Wave on Wave Mike Daly steel guitar , dobro John Jarvis piano on Wave on Wave Sasha Ostrovsky steel guitar on Wave on Wave Waylon Payne acoustic guitar on Elvis , harmony vocals Brent Rowan electric guitar on Wave on Wave Walt Wilkins acoustic guitar on Wrapped , harmony vocals Curtis Wright background vocals on Wave on Wave Chart performance Album class wikitable Chart 2003 Peak br position U.S. Billboard ... size smaller width 45 Hot Country Songs US Country width 45 Billboard Hot 100 US 2003 align left Wave ... more details
acute myocardial infarction is sometimes the hyperacute T wave , which can be distinguished from ... left bundle branch block is present, the T wave should be deflected opposite the terminal deflection of the QRS complex. This is known as appropriate T wave discordance . Frequency of inverted T waves ... more details
In geophysics , Vertical Seismic Profile VSP is a technique of seismic measurements used for correlation with surface seismic data. The defining characteristic of a VSP of which there are many types is that either the energy source, or the detectors or sometimes both are in a borehole. In the most common type of VSP, Hydrophone s, or more often geophone s or accelerometers , in the borehole record reflected seismic energy originating from a seismic source at the surface. A class of borehole seismic measurements used for correlation with surface seismic data, for obtaining images of higher resolution than surface seismic images and for looking ahead of the drill bit also called a VSP. Purely defined, VSP refers to measurements made in a vertical wellbore using geophones inside the wellbore and a source at the surface near the well. In the more general context, VSPs vary in the well configuration, the number and location of sources and geophones, and how they are deployed. Most VSPs use a surface seismic source, which is commonly a vibrator on land and an air gun in offshore or marine environments. VSPs include the zero offset VSP, offset VSP, walkaway VSP, walk above VSP, salt proximity VSP, shear wave VSP, and drill noise or seismic while drilling VSP. A VSP is a much more detailed survey than a check shot survey because the geophones are more closely spaced, typically on the order of 25 m 82 ft , whereas a check shot survey might include measurements of intervals hundreds of meters apart. Also, a VSP uses the reflected energy contained in the recorded trace at each receiver ... the direct path traveltime. In addition to tying well data to seismic data, the vertical seismic profile also enables converting seismic data to zero phase data and distinguishing primary reflections from multiples. There are numerous methods for acquiring a vertical seismic profile VSP . Zero offset ... rig. Drill noise VSPs F , also known as seismic while drilling SWD VSPs, use the noise of the drill ... more details
Body wave may refer to one of the following Body wave seismology , a type of seismicwave s Body wave dance move Body wave hair style Body wave locomotion Body Wave novel , a 2003 novel by Nancy J. Cohen Nancy Cohen Body Wave Inversion Bench , exercise equipment Body Waves , a 1992 comedy film disambig ... more details
The Environmental Seismic Intensity scale ESI 2007 is a seismic scale used for measuring the intensity of an earthquake on the basis of the effects of the earthquake on the natural environment . The international effort to develop a new scale of macroseismic intensity that would focus exclusively on environmental effects of earthquakes has began in the early 1990s and was sponsored by the International Union for Quaternary Research INQUA . After the final draft of the scale was approved by INQUA at its XVII Congress in Cairns , Australia , in 2007, the scale became officially known as ESI 2007 . ref cite book last Clague first John J. title http www.isprambiente.gov.it site files Progetti INQUA ESI 2007 ratification from INQUA.pdf Letter to Prof. Leonello Serva year 2007 month August 3, ref Like many other Seismic scale Seismic intensity scales intensity scales , ESI 2007 uses the basic structure of twelve degrees of seismic intensity and is designed for application during field surveys immediately after the seismic event. However, the definitions of intensity degrees in ESI 2007 are based on the observation of distribution and size of environmental effects produced by an earthquake. This approach makes ESI 2007 a unique diagnostic tool for the assessment of seismic intensity levels X to XII in sparsely populated and uninhibited areas where earthquake effects on people and built environment may not be easily observed. ref The definitions of traditional intensity scales are based primarily on the observation of effects on human s and animal s as well as damages to building s and Nonbuilding structure structures . Therefore they are difficult to apply in earthquake affected areas where such objects of observation are absent or scarce the problem, which the Environmental Seismic ... Seismic scale Other seismic scales br External links http www.isprambiente.gov.it site files Pubblicazioni ... References Reflist Seismic scales Category Seismic scales earthquake stub ... more details
image1 NMSZBig.gif width1 210 caption1 Reelfoot Rift and the New Madrid Seismic Zone in a 3D ... Rift The New Madrid Seismic Zone pronounced IPAc en nj u m d r d , sometimes called the New Madrid Fault Line , is a major seismic zone and a prolific source of intraplate earthquakes earthquakes ... of Memphis ref Earthquakes that occur in the New Madrid Seismic Zone potentially threaten ..., Tennessee Dyersburg . Most of the seismic ity is located between convert 3 and 15 mi km beneath ... without dramatically altering the local topography, studies have concluded that the seismic activity ... tpratt SRL94.pdf title How old is the New Madrid Seismic Zone? last Pratt first Thomas L ... of the New Madrid Seismic Zone first Martitia P. last Tuttle first2 Eugene S. last2 Schweig coauthors .... ref Cite journal title Very Large Earthquakes Centered Southwest of the New Madrid Seismic Zone ... the New Madrid seismic zone and implications for paleoseismicity first RB last Van Arsdale first2 ... nine intensity. A seismic seiche propagated upriver and Little Prairie was destroyed by liquefaction ... Bend , created a wave that propagated upstream and caused the formation of Reelfoot Lake . ref name adsabs.harvard.edu File New Madrid Seismic Zone activity 1974 2011.svg thumb 250px More than 4000 earthquake ... in 1974 to closely monitor seismic activity. Since then, more than 4,000 earthquakes have been ... structure of Reelfoot Rift The New Madrid Seismic Zone is made up of reactivated Geological ..., ref Cite journal title Did deglaciation trigger intraplate seismicity in the New Madrid seismic ... Mafic Body in a Reactivated Lower Crust A Mechanism for Stress Concentration at the New Madrid Seismic .... last2 Zoback year 1997 title Lithospheric strength and intraplate seismicity in the New Madrid seismic ... localized mantle flow below the New Madrid seismic zone last Forte first A. M. first2 J. X. last2 ... seizmic zones USGS.png thumb right 267px Earthquakes in the New Madrid and Wabash Valley seismic zones ... more details
The Northern Applachians Seismic Zone is an active seismic zone in the Appalachian Mountains of eastern North America , extending from New Brunswick southwards into New England and Boston . ref cite web url http earthquakescanada.nrcan.gc.ca zones eastcan eng.php title Earthquake zones in Eastern Canada publisher Natural Resources Canada date 2009 10 13 accessdate 2010 06 24 ref References reflist coord missing United States Category Earthquakes in the United States Category Geology of New Brunswick Category Seismic zones of Canada Category Seismic zones of the United States Canada earthquake stub US earthquake stub ... more details
Unreferenced date May 2008 main Earthquake engineering Mitigation of seismic motion is an important factor in earthquake engineering and construction in earthquake prone areas. The destabilizing action of an earthquake on constructions may be direct seismic motion of the ground or indirect earthquake induced landslide s, soil liquefaction liquefaction of the foundation soils and waves of tsunami . Knowledge of local Amplifier amplification of the seismic motion from the bedrock is very important in order to choose the suitable design solutions. Local amplification can be anticipated from the presence of particular stratigraphic conditions, such as soft soil overlapping the bedrock , or where morphological settings e.g. crest zones, steep slopes, valleys, or endorheic basins may produce focalization of the seismic event. The identification of the areas potentially affected by earthquake induced landslides and by soil liquefaction can be made by geological survey and by analysis of historical documents. Even quiescent and stabilized landslide areas may be reactivated by severe earthquake. Young soil may be particularly susceptible to liquefaction. See also Base isolation Seismic hazard Seismic performance Tuned mass damper Vibration control Crash testing Category Construction terminology Category Earthquake and seismic risk mitigation ja ... more details
The Brawley Seismic Zone BSZ , also known as the Brawley fault zone , is a predominantly extensional tectonic zone that connects the southern terminus of the San Andreas Fault with the Imperial Fault in Southern California . ref name USGS The BSZ is named for the nearby town of Brawley, California Brawley in Imperial County, California . Geology The Brawley seismic zone represents the northernmost extension of the spreading center axis associated with the East Pacific Rise which runs up the axis of the Gulf of California and is in the process of rifting the Baja California Peninsula away from the mainland of Mexico . The Salton Buttes on the south shore of the Salton Sea are on the north margin of the Brawley Seismic Zone and are linked to volcanic and geothermal activity within the zone. The Brawley Seismic Zone has been interpreted as an onshore spreading center which runs diagonally across the Salton Trough . ref name USGS http 3dparks.wr.usgs.gov pp1515 chapter8 fig8 7.jpg Fuis, Cary S. and Walter D. Mooney, Salton Trough Lithospheric Structure and Tectonics from Seismic Refraction and Other Data in USGS Professional Paper 1515 ref References Reflist http adsabs.harvard.edu abs 2006AGUFM.T41D1599B American Geophysical Union, Fall Meeting 2006 California Faults Category Seismic faults of California Category Seismic faults Category Geology of Mexico Category Gulf of California Category Geography of Imperial County, California Category Natural history of Baja California tectonics stub ... more details
hatnote This article is on the type of seismicwave. For the term used in electrocardiography, see P wave electrocardiography . P wave can also refer to a type of electronic wavefunction in atomic physics see atomic orbital . Image Onde compression impulsion 1d 30 petit.gif thumb 305px Plane P wave Image Ondes compression 2d 20 petit.gif thumb 305px Representation of the propagation of a P wave on a 2d grid empirical shape P waves are a type of Linear elasticity Elastic wave elastic wave , called seismic waves in seismology, that can travel through a Continuum mechanics continuum . If the continuum ... by earthquakes and recorded by seismometer seismographs . The name P wave is often said to stand either for primary wave , as it has the highest velocity and is therefore the first to be recorded or pressure wave , ref name John cite book last Milsom first J. title Field Geophysics publisher ... url http books.google.com ?id T7CKj8bqVlwC&pg PA179&dq 22P wave 22 pressure wave geophysics&cd ... of a P wave is always Longitudinal wave longitudinal thus, the particles in the solid have vibrations along or parallel to the travel Direction geometry direction of the wave energy. Velocity The velocity ... through which the wave propagates, and math lambda math is the first Lam parameters Lam parameter ... moduli P wave modulus , math M math , is defined so that math M K 4 mu 3 math and thereby math v p sqrt M rho . math Typical values for P wave velocity in earthquakes are in the range 5 to 8 ... 2009 10 27 accessdate 2011 12 14 ref Seismic waves in the Earth See also Core mantle boundary Mohorovi i discontinuity Low velocity zone Lehmann discontinuity File Speeds of seismic waves.PNG thumb 300px Velocity of seismic waves in the Earth versus depth. ref name Helffrich cite journal journal ... 9.pdf publisher Macmillan Magazines doi 10.1038 35087500 ref The negligible S wave velocity in the outer core occurs because it is liquid, while in the solid inner core the S wave velocity ... more details
The Charlevoix Seismic Zone is a seismically active area in the Charlevoix region of northeastern Quebec , Canada . It is also known as the Charlevoix Kamouraska Seismic Zone because earthquakes occur in Kamouraska Country where the land expression of the seismic zone is separated by the Saint Lawrence River . ref name SI cite web url http earthquakescanada.nrcan.gc.ca zones eastcan eng.php title Earthquake zones in Eastern Canada publisher Natural Resources Canada date 2009 10 13 accessdate 2010 06 24 ref Much seismic activity takes place under the river. ref name SI With over 200 small earthquake s occurring each year, the Charlevoix Seismic Zone is one of the most active seismic zones in Canada. Since 1663, five damaging earthquakes have occurred in the area, including a 1663 Charlevoix earthquake magnitude 7.0 event in 1663 , a magnitude 7.0 event in 1791, a magnitude 6.0 event in 1860, a magnitude 6.5 event in 1870 and a 1925 Charlevoix Kamouraska earthquake magnitude 6.2 event in 1925 . Because of these concerns, the Charlevoix Seismic Zone is considered to be a highly hazardous earthquake zone and it is comparable to those in British Columbia where earthquakes are due to movement of the Earth s plate tectonics tectonic plates . In contrast, the Charlevoix Seismic Zone lies in the interior of the North American Plate and its origin is not well known. ref http www.cseg.ca publications recorder 2004 10oct 10oct earthquakes.pdf Earthquakes of the Charlevoix Seismic Zone, Quebec ref See also Saint Lawrence rift system References reflist coord missing Quebec Category Earthquakes in Quebec Category Saint Lawrence River Category Seismic zones of Canada Canada earthquake stub Canada geology stub Quebec stub ... more details
Wave propagation is any of the ways in which wave physics wave s travel. With respect to the direction ... wave and transverse wave s. For electromagnetic wave s, propagation may occur in a vacuum as well as in a material medium. Most other wave types cannot propagate through vacuum and need a transmission medium to exist. Another useful parameter for describing the propagation is the wave velocity that mostly depends on some kind of density of the medium. Wave velocity see phase velocity group velocity signal velocity Image Seismicwave prop mine.gif thumb 400px right Seismicwave propagation in 2D modelled using FDTD method in the presence of a landmine Wave velocity is a general concept, of various kinds of wave velocities, for a wave s phase waves phase and speed concerning energy and information ... a point of constant phase waves phase of the wave will travel for a discrete frequency. The angular ... . For instance electromagnetic wave s in vacuum are non dispersive. In case of other forms of the dispersion ... which the waves propagate and on the type of waves for instance electromagnetic wave electromagnetic , sound wave sound or ocean surface wave water waves . For sound waves, the denser a medium is, the faster ... among them at a greater rate. The speed at which a resultant wave packet from a narrow range of frequencies ... relation math v g frac partial omega partial k math In almost all cases, a wave is mainly a movement ... Scattering Wave References cite book author A.E.H. Love title A Treatise on The Mathematical Theory ... Weisstein url http scienceworld.wolfram.com physics WaveVelocity.html title Wave velocity work ScienceWorld year accessdate 2009 05 30 External links http www.kuleuven.be bwm edt A matlab toolbox for seismicwave propagation at Katholieke Universiteit Leuven http math.ucr.edu jdp Relativity EM Propagation.html Animation How an electromagnetic wave propagates through a vacuum http www.acoustics.salford.ac.uk feschools waves propagation.htm Propagation of sound waves Category Wave mechanics af ... more details
math r math represents the distance the wave has traveled from the earthquake. Surface waves therefore ... University accessdate 2009 07 28 ref See also Longitudinal wave P wave S wave Rayleigh wave References ... of seismic waves references Category Geophysics Category Waves Category Seismology and earthquake ... more details
The Seismic Hazard Mapping Act The Act was enacted by the California legislature in 1990 following the Loma Prieta earthquake of 1989. The Act requires the California State Geologist to create maps delineating zones where data suggest amplified ground shaking, liquefaction , or earthquake induced landsliding may occur seismic hazard zones . The Act requires responsible agencies to approve only projects within seismic hazard zones following a site specific investigation to determine if the hazard is present and inclusion of appropriate mitigation s if so. The Act also requires disclosure by real estate sellers and agents at the time of sale if a property is within one of the designated seismic hazard zones. The Act called for the creation of an advisory board to the State Mining and Geology Board to advise on the Act s implementation. In a 2004 update to the seismic hazard zone mapping guidelines, this advisory body concluded the amplified ground motion hazard was already sufficiently addressed by the 2001 California Building Code. Consequently, zones for this hazard are not being mapped by the State Geologist. External links http law.justia.com california codes prc 2690 2699.6.html Seismic Hazards Mapping Act Category 1989 in law Category Disaster preparedness in the United States Category Legal articles without infoboxes disaster stub ... more details
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