Estimation of the stress levels in the focal region before and after the 2001 M=8.1 Western Kunlun Mountain Pass earth-quake

Introduction A great earthquake of M=8.1 occurred at 17h26min14.7s (Beijing time) on November 14, 2001 on the eastern Kunlun fault, near Bukadaban mountain peak with an elevation of about 6 866 m in the Qinghai-Xizang (Tibetan) Plateau of western China. The micro-epicenter is at a site of 36.2°N, 90.9°E, and the macro-epicenter is at a site of 35.6°N, 94.1° E, about 300 km west to the Kunlun Mountain Pass.This event is the largest one since 1951 in China, and yet the first su-per-st…

Estimation of the stress levels in the focal region before and after the 2001 M=8.1 Western Kunlun Mountain Pass earthquake

A method estimating the stress level in the focal region of an earthquake is proposed here. Taking the 2001 M=8.1 Western Kunlun Mountain Pass earthquake as an example, we estimate its stress level in the focal region before and after it by this method. The results show that the stress level in the focal region just prior to the initiation of this event is approximately 6.3~8 MPa, and about 5~6.7 MPa remained in the focal region after its occurrence. The stress in the focal region decreased by roughly twenty percent after this event.