地质学报2017，Vol.91Issue(3)：499-509,11.
青藏高原东北缘新近纪盆地内旋转-平推式滑坡聚集规律与机理研究
The Accumulation Characteristics and Mechanism of Rotational-Translational Landslides in the Neogene Basins on the Northeastern Margin of Tibet Plateau
摘要
Abstract
The rotational-translational landslides occur widely within the Neogene basins throughout the world because of their high risk.Based on field survey,this paper summarized the distribution features and geometric strain models of rotational-translational landslide to analyze the dynamic mechanism of nearly horizontal sliding band transformation using the experiment and numerical simulation calculation.The study yields the following understanding.(1) The rotational-translational landslides mainly occur in the Pliocene mudstone basins on the northeastern margin of Tibet Plateau.The activity intensity of these landslides is mainly affected by the uplift process of Tibet Plateau,with the volume gradually reducing from the hinterland of the Plateau to the marginal basin.The giant landslides concentrate in the upstream areas of the Yellow River system,while the large ones distributed respectively in the downstream areas.(2) The slide mass of rotational-translational landslide are all composed of Pliocene mudstones with high clay contents and over-consolidation features.Under the environment of nearly horizontal shear stress of slide mass,which is controlled by water flow erosion,clay grains of over-consolidated mudstones within shear stress zones,with internal friction angle below 10,tend to directional alignment and present ductile and brittle deformation.(3) The sliding surfaces extend along weak layers with high clay content and low calcium content due to the deformation of creep and crack.This process is also accelerated with increasing content of pore water and the rheology of sliding zone.Therefore,the macro movement of sliding mass was determined by creep and glutinous flow of clay minerals in sliding zones,which is one of the driving factors of landslip deformation.关键词
青藏高原/新近纪盆地/旋转-平推式滑坡/聚集规律,机理Key words
Tibet Plateau/the Neogene basins/rotational-translational landslides/accumulation characteristics/mechanism引用本文复制引用
辛鹏,董晓娟,吴树仁,石菊松,王涛,梁昌玉..青藏高原东北缘新近纪盆地内旋转-平推式滑坡聚集规律与机理研究[J].地质学报,2017,91(3):499-509,11.基金项目
本文为中国地质调查局项目(编号1212011220088)与国家自然科学基金项目(编号41402281)联合资助的成果. （编号1212011220088）
