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中国西南四川省宝兴河上有一大型岩质滑坡,大约发生在3～5万年的B.P时期,形成堰塞湖,沉积了的厚40多m的湖相地层。由于滑坡体巨大,顺江宽度达500m,滑体组成物质密实度高,估计密度P>2t/m~3,孔隙率低,再者上游来水量不足,洪水量小,塞湖衰亡时未能将滑坡体冲溃恢复原河道,故现滑坡体下掩埋着约500m长一段故河道,其冲积物厚度约60m。新河床系沿滑体前缘与岸坡接触带冲蚀下切,为基岩锓蚀河床,基岩岸坡坡度达60°,河谷甚窄,水面宽不足10m,水流湍急,平面上河段呈弧形。在滑坡体上游200多m河床进行钻探,钻孔揭示出河床覆盖层厚度近120
There is a large-scale rocky-landslide on the Baoxing River in southwest China’s Sichuan Province, which occurred in B.P. period of 3 to 50000 years to form a barrier lake and a sedimentary lacustrine formation more than 40 m thick. Due to the huge landslide, the river width of 500m along the river, the material composition of the slide body is high, the density is estimated to be 2t / m ~ 3, the porosity is low, and there is not enough water flow in the upper reaches and the flooding is small. The landslide body will be recovered and restored to the original river course. Therefore, a river course of about 500m in length is buried beneath the existing landslide body and the alluvial sediment thickness is about 60m. The new river bed along the slippery front and the slope contact with the erosion undercut, bedrock corrode the riverbed, bedrock slope slope of 60 °, the valley is very narrow, the water is less than 10m wide, rapid current, the river plane arc shape. Drilling at more than 200 m upstream of the landslide reveals that the thickness of the river bed cover is nearly 120