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肖荣久 《地球科学与环境学报》1991,(1)
横山滑坡是一个具有多层滑带且处于蠕滑挤压阶段的新生滑坡。研究表明,由于雨季降水和地表水渗入倾向(氵居)水河、倾角呈10°～15°的潜在多层滑带内,导致主滑带岩石泥化和软化并形成塑性蠕滑区段,滑体在自重压力作用下沿滑带蠕动,形成滑坡。降水和地表水渗入,造成滑带岩石泥化和软化,使岩石强度降低,是滑坡形成的主要原因;山坡超挖过陡和具有宽阔的临空地带等,是滑坡形成的重要因素和条件。而因煤层采空而形成的冒落,不是引起滑坡发生的原因。 相似文献
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基于剩余推力法的地震滑坡永久位移研究 总被引：5，自引：0，他引：5
基于剩余推力法思想 ,结合Newmark有限滑动位移法 ,考虑了由于动力作用造成的孔隙水压力变化 ,对一种最为常见的边坡灾害滑坡 ,提出了一种简便的估算地震动力永久位移的方法。对一实例用该法和快速拉格朗日元 (FLAC3D)进行对比计算 ,结果表明两者的结果基本接近 ,前者要保守一些。这就使得应用剩余推力法这一常规方法对滑坡进行真正意义上的动力时程分析成为可能. 相似文献
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滑坡坝及形成的堰塞湖在世界各国特别是山区一带广泛分布。它能够形成天然水库 ,在发生溃坝和洪水漫坝的情况下 ,造成的灾害损失很大。历史上产生过许多天然滑坡坝 ,有些很快发生溃坝 ,有些存在时间很长。存在时间较长的滑坡坝 ,它周围风景秀丽 ,成为旅游热点地区 ,同时也可开发其水资源。滑坡坝的形成有滑坡堵江、崩塌堵江和泥石流堵江 3种形式 ,它的形成机制对于滑坡坝的存在时间起了重要的作用。在开发和利用滑坡坝时 ,它的成因机制需要分析评价。本文对某滑坡坝的形成机制进行了研究 ,在研究某滑坡坝时发现 ,它由左右两岸的滑坡共同作用形成 ,这种形成模式在国内外报道很少 ,对类似工程也有一定的借鉴意义 相似文献
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《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(2):57-70
The Gauldal disaster of September, 1345, with 500 assumed killed, is the largest recorded in Norway. Contemporaneous written accounts, oral tradition and geological interpretations express divergent opinions about both its location and development. We show that, contrary to tradition, the river Gaula found its present course at Gaulfossen more than 2000 years before the disaster. Lakes in a small, elevated tributary valley, Langdalen, probably represented the 'lost lake' Hagevatnet of oral tradition, and the disaster apparently started with a flood from these lakes. Erosion of an old ice-front delta in the main valley induced a large slide from the eastern side of the valley, which dammed the river Gaula. Failure of the resulting sand and gravel dam would have developed very rapidly, compared to the clay dam postulated by previous workers, and would explain the dramatic results of the downstream deluge. Our data and interpretion fit oral tradition, accounts in the contemporaneous Icelandic Skålholt Annals, and the geological constraints better than previous models. 相似文献
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震源参数的构造物理方法分析结果和实际震例资料表明,断层错动速度Vsei与应力降△τsei成正比关系,而二者的比值Ω(=Vsei/△τsei)受主应力作用方向(以错动角θ表示)的影响。对于大量震例来说,比值Ω的频数分布近似于正态分布,其平均值约为0.092,相当于震源的优势错动角60—61°。Vsei与△τsei之间的正比关系进一步证明选用应力降作为震源突发失稳判别指标的合理性。Ω对θ的依存关系,则有可能为估计主应力方向提供一条新的途径 相似文献
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Morphological features observed in both swath bathymetry and seismic reflection data are not unique, which introduces uncertainty as to their origin. The origin of features observed in the Humboldt Slide has generated much controversy because the same features have been interpreted as a submarine failure deposit versus current-controlled sediment waves. It is important to resolve this controversy because similar structures are observed on many continental margins and the origin of these features needs to be understood. Anisotropy of magnetic susceptibility (AMS) measurements on sediment samples acquired from the Humboldt Slide reveal that the top 8 m have not experienced post-depositional deformation. This suggests that these features are formed by primary deposition associated with downslope currents. Using the same AMS technique on a core acquired north of the Humboldt Slide in a region with no geophysical evidence for post-depositional deformation, we were able to identify a 1 m thick deposit that appears to be a small slump. 相似文献