Affiliation:
1. Institute of Geophysics ,Unversity of Tehran
Abstract
Abstract
In this study, we picked Moho reflected phases and used them to estimate the spatial variation of the Moho depth in northwestern Iran. Moho reflected phases are secondary phases which can be observed at the distance range between 60 and 200 km. We used earthquakes with depth shallower than 40 km that occurred from 1996 to 2017 and collected the approximate travel-time of 200 PmP and 150 SmS high quality phases recorded by 15 seismic stations. We used the differential travel-time of direct and Moho reflected phases to estimate the depth of Moho. The results of the reflected phases PmP and SmS are very similar in character. Although differences are also observed, especially in the northern part of the studied area where piercing points are not well distributed. The results of the inversion of P data are more reliable owing to the accuracy of the picking of P- compared to S- phases. According to the results, the depth of Moho is in order of 45 km in the south part of NorthTabriz Fault and shallower towards eastern part of the study area beneath the Talesh Mountains, 43.2 km. Moho increases from the north Tabriz fault to south of the study area and becomes approximately 45 km.
Publisher
Research Square Platform LLC
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