Matches in SemOpenAlex for { <https://semopenalex.org/work/W2476803575> ?p ?o ?g. }
- W2476803575 endingPage "323" @default.
- W2476803575 startingPage "307" @default.
- W2476803575 abstract "Abstract Shear-wave splitting with 20 to 120 msec time separation is observed on 3-component seismograms from earthquakes occurring at depths of 5 to 18 km in the crystalline basement beneath the Los Angeles basin. Shallow events that occur in the basement at the base of the 5-km-thick sedimentary section exhibit little splitting, while deeper events show progressively greater splitting with depth. The polarization direction of the fast shear wave is N-S, independent of the azimuth of ray path between the event and station. We interpret that the shear-wave splitting occurs mainly in the crystalline basement and is the result of vertical crustal microcracks aligned in N-S direction. Under the assumption that the alignment of microcracks is due to the subsurface stress regime, the results from the shear-wave splitting data yield a maximum principal stress direction of N-S ± 15° at depth beneath the northern Los Angeles basin, consistent with results from geological mapping and fault-plane solutions. Ray trace modeling indicates that the observations of shear-wave splitting can be explained in terms of an anisotropic basement containing vertical microcracks aligned in the N-S direction and with a crack density of ∼0.04, overlain by a weakly anisotropic sedimentary section with a crack density less than 0.02. During the last 4 yr, three major earthquakes occurred in the Los Angeles basin area. They are the M 4.6 and M 4.4 Montebello double earthquakes of 1989, the M 5.5 Upland earthquake of 1990, and the M 5.8 Sierra Madre earthquake of 1991, with epicenters of 10, 55, and 40 km away from the recorder site SCS located in the northern Los Angeles basin, respectively. We did not observe significant variations of shear-wave splitting at SCS before and after the Upland and Sierra Madre earthquakes. However, we found fairly rapid variations of shear-wave splitting following the Montebello events. The time separation between the split shear waves sharply decreased from 70 msec to less than 20 msec after the mainshock and then returned to the average level gradually. This rapid decrease in shear-wave splitting may be a temporal variation or a result of location variations of the Montebello events that were located approximately where the line singularity is expected." @default.
- W2476803575 created "2016-08-23" @default.
- W2476803575 creator A5029587382 @default.
- W2476803575 creator A5036879018 @default.
- W2476803575 creator A5080777065 @default.
- W2476803575 date "1994-04-01" @default.
- W2476803575 modified "2023-09-28" @default.
- W2476803575 title "Shear-wave splitting observations in the northern Los Angeles basin, Southern California" @default.
- W2476803575 cites W1608824372 @default.
- W2476803575 cites W1966410883 @default.
- W2476803575 cites W1979922251 @default.
- W2476803575 cites W1985751998 @default.
- W2476803575 cites W1986579295 @default.
- W2476803575 cites W1987007071 @default.
- W2476803575 cites W1988462334 @default.
- W2476803575 cites W1990868660 @default.
- W2476803575 cites W2004273542 @default.
- W2476803575 cites W2006730264 @default.
- W2476803575 cites W2006963925 @default.
- W2476803575 cites W2013110590 @default.
- W2476803575 cites W2016103475 @default.
- W2476803575 cites W2034644511 @default.
- W2476803575 cites W2041158022 @default.
- W2476803575 cites W2042449523 @default.
- W2476803575 cites W2055563758 @default.
- W2476803575 cites W2062503107 @default.
- W2476803575 cites W2066257818 @default.
- W2476803575 cites W2066808192 @default.
- W2476803575 cites W2069898886 @default.
- W2476803575 cites W2071407214 @default.
- W2476803575 cites W2076635761 @default.
- W2476803575 cites W2086595659 @default.
- W2476803575 cites W2087215540 @default.
- W2476803575 cites W2088395555 @default.
- W2476803575 cites W2092125588 @default.
- W2476803575 cites W2098361644 @default.
- W2476803575 cites W2100423981 @default.
- W2476803575 cites W2105325334 @default.
- W2476803575 cites W2106081362 @default.
- W2476803575 cites W2119300386 @default.
- W2476803575 cites W2122815024 @default.
- W2476803575 cites W2134374797 @default.
- W2476803575 cites W2136246829 @default.
- W2476803575 cites W2142173963 @default.
- W2476803575 cites W2152988800 @default.
- W2476803575 cites W2162169366 @default.
- W2476803575 cites W2162590174 @default.
- W2476803575 cites W2163035644 @default.
- W2476803575 cites W2165411621 @default.
- W2476803575 cites W2170573689 @default.
- W2476803575 cites W2318586775 @default.
- W2476803575 cites W3121560237 @default.
- W2476803575 cites W1751682257 @default.
- W2476803575 cites W2799120805 @default.
- W2476803575 doi "https://doi.org/10.1785/bssa0840020307" @default.
- W2476803575 hasPublicationYear "1994" @default.
- W2476803575 type Work @default.
- W2476803575 sameAs 2476803575 @default.
- W2476803575 citedByCount "6" @default.
- W2476803575 countsByYear W24768035752012 @default.
- W2476803575 crossrefType "journal-article" @default.
- W2476803575 hasAuthorship W2476803575A5029587382 @default.
- W2476803575 hasAuthorship W2476803575A5036879018 @default.
- W2476803575 hasAuthorship W2476803575A5080777065 @default.
- W2476803575 hasConcept C109007969 @default.
- W2476803575 hasConcept C114793014 @default.
- W2476803575 hasConcept C120665830 @default.
- W2476803575 hasConcept C121332964 @default.
- W2476803575 hasConcept C127313418 @default.
- W2476803575 hasConcept C127413603 @default.
- W2476803575 hasConcept C147176958 @default.
- W2476803575 hasConcept C151730666 @default.
- W2476803575 hasConcept C159737794 @default.
- W2476803575 hasConcept C165205528 @default.
- W2476803575 hasConcept C169744125 @default.
- W2476803575 hasConcept C200646496 @default.
- W2476803575 hasConcept C22512106 @default.
- W2476803575 hasConcept C2524010 @default.
- W2476803575 hasConcept C2779438780 @default.
- W2476803575 hasConcept C2781297371 @default.
- W2476803575 hasConcept C33923547 @default.
- W2476803575 hasConcept C5900021 @default.
- W2476803575 hasConcept C6494504 @default.
- W2476803575 hasConcept C77928131 @default.
- W2476803575 hasConcept C85725439 @default.
- W2476803575 hasConcept C96035792 @default.
- W2476803575 hasConceptScore W2476803575C109007969 @default.
- W2476803575 hasConceptScore W2476803575C114793014 @default.
- W2476803575 hasConceptScore W2476803575C120665830 @default.
- W2476803575 hasConceptScore W2476803575C121332964 @default.
- W2476803575 hasConceptScore W2476803575C127313418 @default.
- W2476803575 hasConceptScore W2476803575C127413603 @default.
- W2476803575 hasConceptScore W2476803575C147176958 @default.
- W2476803575 hasConceptScore W2476803575C151730666 @default.
- W2476803575 hasConceptScore W2476803575C159737794 @default.
- W2476803575 hasConceptScore W2476803575C165205528 @default.
- W2476803575 hasConceptScore W2476803575C169744125 @default.
- W2476803575 hasConceptScore W2476803575C200646496 @default.