Shear Wave Splitting in the Caucasus Mountains

Session: Advances in Seismic Imaging of Earth’s Mantle and Core and Implications for Convective Processes [Poster]
Type: Poster
Date: 4/29/2020
Time: 08:00 AM
Room: Ballroom
Description: 

The Caucasus Mountains are one of the best places to study early stages of mountain formation and mechanisms, as most of the uplift and volcanism has occurred in the recent geologic past. To study this, we have determined shear wave splitting parameters from the Caucasus Seismic Network (CNET). CNET is a network of 116 broadband seismic stations distributed as a linear transect and 2-D array through the countries of Georgia, Armenia, Azerbaijan, and Russia. Our results show that fast polarization directions are generally NE-SW throughout the Lesser Caucasus, with average lag times of 0.8 s and similar to previous studies investigating Turkey. Closer to the Greater Caucasus, fast polarization directions rotate and become parallel to the Greater Caucasus Range and rotate clockwise towards Azerbaijan in the Kura Basin, with average lag times of 1.4 s, and 1.0 s, respectively. These results coincide with other studies done in the East Anatolian Plateau and the Kura Basin. The azimuthal variation in these preliminary results is uncertain, as the lag times from events coming from similar azimuths vary more than expected. This work is in progress and will be supplemented with results from local networks to increase the resolution of anisotropy in the region. These results give us insight into the upper mantle strain fabrics and anisotropy of the region, and can help us understand the mechanisms and geodynamics under the Caucasus Mountains.

Presenting Author: Luis B. Martinetti

Authors