The M 8.0 Wenchuan earthquake of 12 May

2008 generated three surface rupture zones along the Longmenshan fault zone.The complex rupture process generated various phenomena which proved multiple faults have joined in.The Xiaoyudong surface rupture zone and the intersection area of the other two surface rupture zones are investigated in this paper

and the characteristics and distribution of Xiaoyudong surface rupture zone are summarized.The Xiaoyudong surface rupture zone is located near the Xiaoyudong town

Pengzhou city.It is a coseismic surface rupture zone in the M 8.0 Wenchuan earthquake

characterized as NW-thrust fault with sinistral strike-slip displacement.Our research shows that the Xiaoyudong surface rupture zone has different characteristics in each segment: The maximal horizontal and vertical displacement is located in the middle segment in the Xiaoyudong town;The horizontal and vertical displacement of south segment is gradually diminishing towards the southeast of Xiaoyudong town;The north segment

in the mountains to the northwest of Xiaoyudong town

mainly demonstrates thrust activity.