| On May 12, 2008, in WenChuan SiChuan, 8.0 earthquake, resulted mountain broken into pieaces , the river changes, as well as a series of secondary landslide, landslides, debris flows, and other mountainous geological disasters. ,in particular, the landform and landscape of earthquake area were extremely changed. It is a serious threat to peoples' lives and property and socio-economic development. For a long time people are always affected passively in natural disasters.and It is very difficult to use traditional field survey methods. With the development of remote sensing technology, remote sensing technology is regarded as the most effective way in disaster warning and investigation of disasters with its rapid, mobile, observation from macroscopic to microcosmic conditions. and it rapidly displays its gigantic application potential.This paper takes WenChuan County hit severely by earthquake as the studying area , adopts remote sensing technique as a main means , takes aerial image and IKONOS with high space resolution as data source, with three-dimensional visualization techniques for supporting , implements the the man-machine interactive interpretation with multi-platform for remote sensing images, verifies the results of interpretation by field work and analysis of the results of regional geological environment characterized, explores the spatial distribution of geological disasters in the study area.The main results are shown as following:(1)The technology of 3D Visualization1 is adopted to superpose DEM with Remote-Sensing orthoimage of high-aeeuracy to bui??D remote-sensing model so as to provide real and visual images of ground landscape that can be used repeatedly and continuous animation, and assist the information extraction of geologieal disasters and macro-acquaintance for decision maker of the study area.(2) The study area covered by the scope of remote sensing images has been achieved with an area of 700.42 km~2. In the the scope of interpretation, Wenchuan County has 149 landslides, 3336 collapses, 25 landslides, the area of disasters is 94.37 km~2.(3) Explored the relationship of spatial distribution in the area between geological disasters (mainly landslides and avalanches) and lithology, landform (elevation and slope), water, fault.①Lithology and its combination relations not only control the development and distribution of the landslides, collapse, but aslo restricts the way and scale of its activities. In the granite region of Wenchuan County, geological disasters are developed to a big scale. the number of landslides is 1144. disaster area reaches 32.84 km~2.and the grey green-purplish red metabasic-medium acidic volcanics, clastic rocks, carbonate rocks are in the second.②From the distribution of development condition of geological disasters in defferent Elevation scopes, the favorable ones in Wenchuan County are 1400 ~ 1700m, 1100 ~ 1400m, 1700 ~ 2100m, > 2100m, followed by 800 ~ 1100m. As can be seen, geological disasters in the area is mainly distributed in valley. With large population density , well developed transportation, the construction of railways, highways, drainage and other unreasonable engineering and constructive projects damaging the surface vegetation, artificial transformation of natural landscapes break the structure and stability of the mountain.③In Wenchuan County area , ??advantageous slope sector for the geological disaster is 40~60°, then 25~40°,10~25°,60~90°,0~10°in turn. 40 ~ 60°interval can be the advantage slope angle for geological disasters. In the same Seismic stress condition, rock debris objects on the steep slope is more easily off from the mountain under the effects of gravity and the river scours the mountain on both sides, making the uncertainty increase.④Statistics of geological disasters near the water distribution in Wenchuan County shows that the more near from water , the greater the density of geological disasters; at 400m from the scope of water system, the number of geological disasters in Wenchuan County accounted for 70.47% of the total number of disasters, which determines the water the impact, up to 400m,.that is, from both sides of the 400m distance to the water system within the scope , the relationship between the geological disasters and the water is more closely. ⑤It is the region within 1000m from the faults that the geological disasters in Wenchuan County are spreading fast, then followed by > 3000m, 1000 ~ 2000m, 2000 ~ 3000m.The survey showed that remote sensing technologies, with the use of multi-platform, high space resolution remote sensing data for rapid survey geological disasters after the earthquake, can provide the very important basic data in time for monitor, disaster assessment, post-disaster reconstruction.
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