The Longmen Mountains thrust belt is located in the western margin of Sichuan Basin in China and the collision belt between the Yangtze plate and Songpan-Ganzi fold belt. The northern end of which connects with the EW-trending Qi-Qin-Kun tectonic belt and the southern end connects with the Kang-Dian NS-trending tectonic belt. The thrust belt is one of the most important earthquake zones of China and where many huge earthquakes occurred in history. 26 destructive earthquakes and more than 20 earthquakes which are over 6 magnitude have taken place since 1169 in all. The M8.0 Wenchuan earthquake, which occurred on May 12, 2008, showed that the Longmen Mountains thrust belt is still an active tectonic zone. An in-depth study on the Longmen Mountains is necessary in order to achieve the purpose of earthquake prevention and disaster reduction. The traditional structural analysis, which combined with the thought of the structural belt, is applied in this paper.
