Coseismic reverse- and oblique-slip surface faulting generated by the 2008 Mw 7.9 Wenchuan earthquake, China.
Shaw, John H.
Date of Issue2009
School of Physical and Mathematical Sciences
The Mw 7.9 Wenchuan, China, earthquake ruptured two large thrust faults along the Longmenshan thrust belt at the eastern margin of the Tibetan Plateau. This earthquake generated a 240-km-long surface rupture zone along the Beichuan fault and an additional 72-km-long surface rupture zone along the Pengguan fault. Maximum vertical and horizontal offsets of 6.5 m and 4.9 m, respectively, were measured along the Bei chuan fault. A maximum vertical offset of 3.5 m was measured along the Pengguan fault. Coseismic surface ruptures, integrated with aftershocks and industry seismic profiles, show that two imbricate structures have ruptured simultaneously, resulting in the largest continental thrust event ever documented. Large oblique thrusting observed during this earthquake indicates that crustal shortening is an important process responsible for the high topography in the region, as everywhere along the edge of Tibetan Plateau.
DRNTU::Science::Geology::Volcanoes and earthquakes
© 2009 Geological Society of America.