Surface Rupture and Co‐seismic Displacement Produced by the Ms 8.0 Wenchuan Earthquake of May 12th, 2008, Sichuan, China: Eastwards Growth of the Qinghai‐Tibet Plateau

An earthquake of Ms 8 struck Wenchuan County, western Sichuan, China, on May 12(th)., 2008 and resulted in long surface ruptures (>300 km). The first-hand observations about the surface ruptures produced by the earthquake in the worst-hit areas of Yingxiu, Beichuan and Qingchuan, ascertained that the causative structure of the earthquake was in the central. fault zones of the Longmenshan tectonic belt. Average co-seismic vertical displacements along the individual fault of the Yingxiu-Beichuan rupture zone reach 2.5-4 in and the cumulative vertical displacements across the central and frontal Longmenshan fault belt is about 5-6 m. The surface rupture strength was reduced front north of Beichuan to Qingchuan County and shows 2-3 in dextral strike-slip component. The Wenchuan thrust-faulting earthquake is a manifestation of eastward growth of the Tibetan Plateau tinder the action of continuous convergence of the Indian and Eurasian continents.