Crustal Rheology and Links to Possible Uplift Mechanisms Revealed by Lg-Wave Attenuation Tomography in the Anatolia Plateau

Session: Advances in Upper Crustal Geophysical Characterization [Poster]
Type: Poster
Date: 4/29/2020
Time: 08:00 AM
Room: Ballroom
Description: 

Located in the Alpine-Himalayan orogenic belt, the Anatolian plate is experiencing the westward extrusion withstanding the Arabia-Eurasia collision in the east and oceanic subduction along Hellenic-Cypean Trench in the west (Schidgen et al., 2014). Several geodynamic mechanisms, such as slab break-off, lithospheric delamination and dripping, were invoked to explain the uplift of the entire Anatolian plateau (Delph et al., 2017; Göğüş et al., 2017). In the purpose of investigating the rheological properties of crustal materials influenced by the deeper uplift mechanisms, we utilize the joint tomography method (Zhao et al., 2010, 2013) to obtain a Lg-wave attenuation model (1°×1°) for the Anatolian plateau and surrounding regions. The Lg-wave attenuation results reveal strong lateral variations which correspond well with regional tectonics. Specifically, our Lg-wave Q model shows the large-scale low region beneath eastern Anatolia and a low zone parallel to the strike of Eastern Anatolian Fault Zone (EAFZ). These low regions correspond well with the zones of low seismic velocity and low resistivity may indicate the lateral crust flow, which is due to hot mantle upwelling following slab break-off and subsequent tectonic escape of the Anatolia plate. In addition, two low regions, which are separately distributed in the north and south of the central Anatolian plateau, corresponding to where Neogene volcanics are developed, may represent the very places where the partial melting exists due to dripping-derived mantle upwelling. This style of thermal heating from asthenospheric materials intrusion on the crust support that lithospheric dripping may cause the uplift over the entire central Anatolia.This research is supported by the National Natural Science Foundation of China (grants 41630210, 41674060) and the Special Fund of China Seismic Experimental Site (2019CSES0103)

Presenting Author: Weimou Zhu

Authors