EARTH SCIENCES RESEARCH JOURNAL Earth Sci. Res. J. Vol. 20, No. 4 (December, 2016): A1 -A8 GEODYNAMICS Deep physical structure and geotectonic implications of the eastern margin of the Qinghai–Tibet Plateau Jun Lia,b*, Xuben Wang a,b, Qingyan Qin c, Gang Zhang d, Dahu Lie, Jun Zhou a,b a Key Lab. of Geo-Detection & Information Techniques of Ministry of Education, Chengdu, China b College of Geophysics, Chengdu University of Technology, Chengdu, China c College of Resources and Environmental Engineering, Guizhou Institute of Technology, Guiyang, China d School of Environment and Resource, Southwest University of Science and Technology, Mianyang, China e Sichuan Earthquake Administration, Chengdu, China *Corresponding author:
[email protected] ABSTRACT Keywords: Eastern margin of Qinghai–Tibet The eastern margin of the Qinghai–Tibet Plateau (QTP) is the focus of studies on eastward lateral extrusion of the latter’s crustal Plateau, Bouguer gravity, Long period material. This study aims to explore the structural response of the QTP’s eastern crust–mantle to the extrusion, and the basis for magnetotellurics, Crustal fluid, Apparent density the latter’s geological structure. Data on the long-period magnetotelluric sounding of cross-tectonic units and Bouguer gravity were used to determine the physical structure of the crust–mantle at the plateau’s eastern margin. The findings are as follows: (i) the apparent density structure indicates the large presence of a low-density material in the middle–lower crusts of the Songpan and Sichuan–Yunnan blocks at the QTP’s eastern margin. On the other hand, the Yangtze cratonic block (Sichuan Basin) contains a material with a significantly higher density.