| At 2:28 p.m. on May 12, 2008, a Ms8.0 occurred in Yingxiu town of Wenchuan County in Sichuan Provence. With all the world shocked, the earthquake caused heavy casualties and economic losses. The earthquake caused catastrophic and widespread damage not only near the epicenter and surrounding areas, but also in Sichuan province and neighboring provinces, even the impact is spread to most areas of the country. The Wenchuan Earthquake is the most severely disaster since the establishment of new China in 1949. More than 100,000 km2 had been affected, with both the geographic scope and the heavy loss occurred rarely in many years.The fault which caused the earthquake was the Longmen Shan fault zone, and it is constituted of 3 sets of faults, many strong earthquakes had happened around this area in the history, moreover, it remains active nowadays. The Longmen Shan mountain gorge has strongly cutting terrain, complex geological structure and faults, so it always been a high-incidence area with many kinds of mountain disasters. The earthquake can caused not only direct damage to buildings, roads, facilities, but also a large number of secondary disasters:such as landslides, debris flows, blocked lake.etc. Those secondary disasters destroyed roads, filling rivers, destruction and buried settlements, causing enormous loss of life and property. After the earthquake, the geological environment turned more fragile, combined with the seismic aftershocks, new mountain hazards could easily be triggered if there has heavy rain conditions. So, the local people would be threatened in a long time. Therefore, the prevention and reduction work of the mountain hazards still has a long way to go.The writer has collected basis geographical data and remote sensing data of the study area, through processing and interpretation the high resolution remote sensing image such as SPOT-5, IKONOS, aerial photograph.etc, the mountain disasters after the earthquake of the study area in remote sensing information extraction and verification was completed. Combined with topographic maps and geological maps, as well as by way of combining RS and GIS, the existing data was preliminary processed, so that the mountain hazards and it's relationship between the various affecting factors can get a more comprehensive detailed analysis with the help of geology and geographic characteristics.As a whole, this article write about the density of disaster point distribution and various influencing factors on the development of the mountain hazards, complete the growth law analysis of the earthquake-induced mountain hazards in Beichuan County from the aspects such as elevation, slope aspect, seismic intensity, aftershocks, geological structure, lithology, the upper and lower plate effect, development density, hydrological conditions. After all, it reached a distribution low of mountain disasters and provided a basis for the risk assessment of geological disasters.
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