Recording of Local Earthquakes under the Udina Volcanoes (Kamchatka) by Regional and Temporary Seismic Stations. Refinement of the Ve-locity Model by Reversing the Travel-Time Curve from a Deep Sourceстатья
Информация о цитировании статьи получена из
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 8 сентября 2021 г.
Аннотация:Currently, the Udina volcanoes (Kamchatka, Klyuchevskaya Volcano Group) are consideredextinct. However, at the end of 2017, seismic activation was recorded for the first time since instrumentalobservations beneath them have been carried out at the middle−upper crustal level. To improve the accuracyin determining the coordinates of hypocenters in the vicinity Udina volcanoes, work was carried out to refinethe local velocity model for this area. The velocity structure of the setting was refined using proprietaryapproaches to determining the coordinates of earthquake hypocenters and reversing the travel-time curvesfrom deep sources. Seismic wave propagation velocities were obtained from data on earthquakes of the Udinaseismic activation 2017−2019. The results of the Kamchatka regional seismic network and four additionaltemporary stations installed specifically to study the Udina seismogenic region were used. A one-dimensionalvelocity model was obtained for depths up to 40 km: the set of layers in which the longitudinal wave velocityvaries linearly at a constant ratio VP/VS = 1.85. The model differs significantly from the generalized baselinecurve obtained for the northern part of the Klyuchevskaya Volcano Group based on DSS data DSS. The largestdifferences in velocities are observed in the upper crust (at a depth of up to 4 km) and in the region of the Conrad discontinuity at a depth of ∼20 km In the depth range of 20−25 km, a reduced-velocity layer wasrevealed.