内蒙南部林西县至正镶白旗林西—正镶白旗地区晚二叠世地层中, 发现类型繁多的同生变形构造.除前人报道的滑卷层理、滑塌褶皱、滑塌砾岩和浊积砂砾岩以外, 还有本文首次发现的大量球状体, 包括滚动纺锤体、叠加滑卷球核、砾核滚动球、砂质滚动球和泥质滚动球.形态结构、成分组成和地层分布研究表明, 这些构造形体均属重力成因和形成在陆棚—斜坡上.不同类型的构造形体可以组成来源演变序列, 显示重力作用的加强, 如滑卷层理通过"叠加滑卷"变成滑卷叠加球核, 再通过"滚动粘结"变成滚动球体.它们形成和保存都受特定环境因素控制, 因此各自具有特殊指相意义.大量同生变形构造出现, 反映沿华北板块北缘出现陆棚、斜坡和深水海槽环境, 证明晚二叠世兴—蒙海槽再次裂开, 并形成"林西—九台裂陷带".%Various Late Permian syngenetic deformation structures were found in the Linxi-Zhengxiangbai Banner area, southern Inner Mongolia. In addition to convolute beddings, slump folds and slump breccia reported by previous researchers, a lot of roll spheroids were firstly discovered by the authors, which included roll spindles, over-convolute cores, spheroids with breccia cores, sandy spheroids and muddy spheroids. A study of shapes, textures, compositions and strato-spreading shows that these structures were all formed under the gravitation on land-shelf and slop. In addition, individuals of different kinds could make up the same original series that reflects strengthening of gravity activities, e.g., convolute beddings changed to over-convolute cores through'over-convoluting', and then to roll spheroids by 'roll-pasting'. Due to their formation, rolling and stop are all controlled by specified conditions, so each kind of them serves as excellent facies-indicating marks. The existence of many syngenetic deformation structures prove that the Xingan-Inner Mongolia sea-trough experienced breakup again in the Late Permian, and land-shelf, steep-slop and deep-trough occurred along the north margin of Huabei Platform, where the Linxi-Jiutai faulted depression zone was formed.
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