LOCAL EARTHQUAKE TOMOGRAPHY IN THE BROADER AREA OF WESTERN CORINTH GULF


Published: Jul 27, 2016
Keywords:
Local earthquake Tomography velocity models Salt tectonics Greece
A. Karakonstantis
P. Papadimitriou
Abstract

In this study, we applied Local Earthquake Tomography in order to investigate the detailed 3-D structure within and around the broader region of Western Corinth Gulf which is one of the most seismically active regions in the world. We use data from the 2012-2014 time-period, selecting about 2,000 seismic events recorded by the local seismic stations of Hellenic Unified Seismological Network (HUSN) and the Corinth Rift Laboratory Network (CRLN). Applying Tomographic Inversion, we produce and interpret 3-D models of Vp, Vs and Vp/Vs ratio in the study area. The obtained results shows several distinct structures, namely areas of high and low Vp/Vs ratio correlating the hypocenter distribution with changes in lithology or fluid concentration. In the area of Patraikos Gulf, an ascending velocity volume was traced that could possibly be connected to salt tectonics in the alpine basement, effecting the fluid circulation as well as the behavior of local faults.

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  • Geophysics and Seismology
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