First,the Indian plate subduction to Asia,resulting in rapid uplift of the Qinghai-Tibet Plateau.Slowly east plateau of material flows on the plateau along the eastern edge of the Longmen Shan belt eastward extrusion,rigid block under the Sichuan Basin,encountered stubborn blocked,resulting in a long-term accumulation of tectonic stress energy,culminating in Longmenshan Beichuan - Ying show the sudden release of the region.
Second,the thrust,D,squeeze-type fault earthquake.Seismogenic structure is the central Longmen Shan fault belt,in the extrusion under stress from the southwest to north east thrust movement; the earthquake rupture earthquakes belonging to a one-way,from southwest to north east migration,causing aftershocks north the East to the expansion; compressional thrust-fault earthquakes in the main shock,the stress propagation and release process is relatively slow,and may lead to greater intensity of aftershocks,continuing a long time.
The third is shallow earthquakes.Wenchuan earthquake does not belong to the deep effect of plate boundaries,occurred in the crust brittle - ductile transition zone,focal depth of 10 km - 20 km,so a huge destructive.