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| Titel |
Detecting and locating teleseismic events with using USArray as a big antenna |
| VerfasserIn |
Lise Retailleau, Nikolai Shapiro, Jocelyn Guilbert, Michel Campillo, Philippe Roux |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250091550
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| Publikation (Nr.) |
 EGU/EGU2014-5850.pdf |
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| Zusammenfassung |
| We design an earthquake detection and location algorithm that explores coherence and characteristic behavior of teleseismic waves recorded by a large-scale seismic network. The procedure consists of three steps. First, for every tested source location we construct a time-distance gather by computing great-circle distances to all stations of the network and aligning the signals respectively. Second, we use the constructed gather to compute a Tau-P transform. For waves emitted by teleseismic sources, the amplitude of this transform has a very characteristic behavior with maxima corresponding to different seismic phases. Relative location of these maxima on the time-slowness plane strongly depends on the distance to the earthquake. To explore this dependence, in a third step, we convolve the Tau-P amplitude with a time slowness-filter filter whose maxima are computed based on prediction of global travel-time calculator (Buland and Chapman, 1983). As a result of this three-step procedure, we obtain a function that characterizes a likelihood of occurrence of a seismic event in a given position in space and time. We test the developed algorithm by applying it to vertical-component records of USArray to locate a set of earthquakes distributed around the Globe with magnitudes between 6 and 8. |
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