Study of overthrust nappe structure and its geodynamic mechanism along the southeastern margin of Nansha Trough

Abstract

On the basis of interpretation of comprehensive geophysical data and foreign data analysis, there existed a lot of overburden detachment shear thrust faults along the southeastern margin of Nansha Trough, which composed imbricated overthrust nappe structure. Thrust-faulted nappe structure pattern is determined in this area, which consists of frontal fault zone, thrust fault-folded zone and root zone structures, and presents regularly zonation on plane. The detail description of the structural geometrical characteristics is given in shallow thrust fault zone, and the kinematical mechanism of thrust fault nappe structure is furtherly discussed. Overthrust nappe structure in this area is resulted from island arc-continent collision and orogenic activities.