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正断层作用和盐构造作用对北海中生代和第三纪地层的沉积及随后的变形起着重要的控制作用。除了先前证明了的盐撤离、溶解和差异沉积负裁等机理之外,还认识到了倾斜盐层上重力驱动薄皮拉伸对北海盆地的发育起着重要的作用。工业用剖面复原软件被用来简化由中北海西部的一个解释过的区域数据库所选择的地震剖面的深度转换、复原和脱压实,并能改善解释精度,用图示并定量地描述与盐有关的拉伸。本研究的结果表明:蔡希斯坦群蒸发岩是于二叠纪时期沉积在一个浅凹盆地中的。二叠系透镜体是由蒸发岩之上的向斜盆地和地堑中的局部沉积作用形成的。当可流动的盐充填到背斜核中时,层状的盐发生褶皱。自早侏罗世以来,与裂谷期后沉降有关的区域性掀斜和沉积负荷的增加,致使异地的中生代和第三纪地层因流动盐层之上的重力扩张而拉伸,它使得异地岩体与下伏原地的晚古生界岩体之间产生滑离。上凹的铲状正断层向下消失在盐层中,向上伸展到上覆盖层层序中,并且在各个地质时代活动,造成异体岩体内地层变厚和褶皱。反向和同向正断层发育,生成复杂的向上分支的断层体系。从图上看,铲状断层呈曲线雁行状排列,由转换冲断层连接。断层一般宽3～7km,厚2～3km,长7～10km。侏罗纪—第三纪期间,盐运动是由盖层的活动性拉伸驱动的,导致盐充填到由断块旋转所产生的可能空间中。因此,盐隆起就出现在拉伸位置的下方。铲状断层的倾向通常与盐底面的倾向相同,尽管还有一些较大的反向区域性断层。在拉伸期间,区域倾斜增加到5°左右。它对盐层上的动力驱动拉伸来说是足够了。已出现了约6%的总拉伸。中北海西部已证实的重力驱动的薄皮拉伸是一种在北海盆地别的地方也能识别出的一种现象,并可与安哥拉近海、巴西、Nova Scotia和墨西哥湾已证实的类似现象相对比。
Normal faulting and salt tectonics play an important role in controlling the sedimentation and subsequent deformation of the Mesozoic and Tertiary strata in the North Sea. In addition to previously proven mechanisms of salt evacuation, dissolution and differential deposition, it is also recognized that gravitationally-induced thin-skinned stretching on inclined salt beds plays an important role in the development of the North Sea basin. Industrial Profile Recovery Software was used to simplify the depth conversion, restoration and deselection of seismic profiles selected by an interpreted regional database in the western North China Sea and to improve interpretation accuracy by using graphic and quantitative descriptions Related to stretching. The results of this study show that the Zeiss steatite evaporites were deposited in a dimple basin during the Permian period. Permian lenses are formed by local sedimentation in synclinal basins and graben deposits above evaporites. When the flowable salt is filled into the anticline core, the layered salt folds. Since the Early Jurassic, the increased regional tilting and sedimentation load associated with post-Rift settlement have led to the extension of Mesozoic and Tertiary strata in different places due to the gravity expansion above the flowing salt layer, Slipping off between the rock mass and the underlying Paleozoic pluton in situ. The concave, shoal-like normal faulting disappears downward in the salt layer and extends upward into the upper overburden sequence, and is active during various geologic epochs, causing thickening and folding of the formation within the heterogeneous rock mass. Reverse and co-normal faulting develop into complex up-branched fault systems. From the figure, the shoal-like fault curves in the shape of geese arranged by conversion thrust fault connection. The fault is generally 3 ~ 7km wide, 2 ~ 3km thick and 7 ~ 10km long. During the Jurassic-Tertiary period, salt movement was driven by the active stretching of the caprock, causing the salt to fill up into the possible space created by the rotation of the fault block. As a result, the salt uplift appears below the stretching position. The tendency of shoal-like faults to tend to be the same as that of the bottom of the salt, although there are some larger reverse-direction regional faults. During stretching, the area is tilted to about 5 °. It is enough for the power-driven stretching on the salt layer. Approximately 6% of the total stretch has occurred. Gravity-driven thin-skin stretching, which has been demonstrated in the western North China Sea, is a phenomenon that is also identifiable elsewhere in the North Sea basin and is comparable to the similar phenomena that have been confirmed in offshore Angola, Brazil, Nova Scotia and the Gulf of Mexico .