The <answer>Longmen Shan Fault System</answer> is situated in the eastern border of the Tibetan Plateau and contains several faults. This earthquake ruptured at least two imbricate structures in <answer>Longmen Shan Fault System</answer>, i.e. the Beichuan Fault and the Guanxian–Anxian Fault. In the epicentral area, the average slip in Beichuan Fault was about 3.5 metres (11 ft) vertical, 3.5 metres (11 ft) horizontal-parallel to the fault, and 4.8 metres (16 ft) horizontal-perpendicular to the fault. In the area about 30 kilometres (19 mi) northeast of the epicenter, the surface slip on Beichuan Fault was almost purely dextral strike-slip up to about 3 metres (9.8 ft), while the average slip in Guanxian–Anxian Fault was about 2 metres (6 ft 7 in) vertical and 2.3 metres (7 ft 7 in) horizontal.
Where are the Beichuan and Guanxian-Anxian Faults?
Longmen Shan Fault System