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本区主要发育北东向构造,其北缘弧形构造的存在;逆掩断层、推覆体普遍发育;构造变形自西北至东南出现明显的分带性,成为主要的构造特征。综合研究区内的构造特征及其形成的构造背景后,作者认为主要构造是重力滑的产物。晚三叠世、东南的“江南隆起”、昆嘉大背斜较大幅度地上升,西北的下扬子大向斜相对下降,形成沉积盖层向北西倾斜的产状,为印支期重力滑动提供重要的坡度条件。在其他地质因素配合下,重力驱使岩石层沿斜面由东南向西北滑动。滑动岩石层的前锋在长江一带受阻发生强烈挤压,产生紧闭褶皱、逆掩断层,并构成弧形构造;尾端,由于拉张作用而在浙北地区形成北东向的张性断裂和构造剥蚀带。燕山期,基底断裂发育,块断升降造成岩块的抬升、掀斜为这个时期的重力滑动提供了新的坡度条件,导致了推覆体的发育。重力滑动塑造的构造在空间上有规律的布局为本区寻找油气藏提供了构造依据。
The area is mainly developed in the north-east direction, with the northern arc-shaped structure existing in it. The overthrust and the nappe generally develop. The tectonic deformation has obvious zonation from the northwest to the southeast and becomes the main tectonic feature. After comprehensively studying the tectonic features in the study area and the tectonic setting of the tectonic setting, the author believes that the main structure is the product of gravity slip. In the Late Triassic, the southeastern “uplifted Jiangnan”, the Kunjia anticline risen sharply and the Lower Yangtze subtropical syncline relatively decreased. The sedimentary caprock tilted toward the northwest and formed the Indosinian gravitational slip Provides important grade conditions. In cooperation with other geologic factors, gravity forces the rock layer to slide along the slope from southeast to northwest. The front of the sliding rock layer was strongly crushed in the hinterland of the Yangtze River, resulting in tight folds, overthrusting the fault and forming an arc structure. At the tail end, the northeastern Zhang-Zhang fault was formed due to the tension effect Construction of denudation zone. During the Yanshanian period, the basement faults developed and the blocks lifted and caused the rock block to lift. The tilting provided a new gradient condition for the gravity sliding during this period, which led to the development of the nappe. The structure of gravity sliding mode provides a structural basis for finding the oil and gas reservoir in this area in a spatial and regular layout.