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东海陆架盆地位于欧亚板块、太平洋板块及菲律宾海板块的会聚交接带,是研究全球性构造体制转化事件的关键区域之一。通过物理砂箱实验方法模拟了东海陆架盆地南部瓯江凹陷、雁荡低凸起、闽江凹陷、台北低凸起及基隆凹陷几个构造单元中生代组合关系与演化过程。研究发现东海陆架盆地中生代的成盆过程及属性与中生代时期依泽奈崎板块的俯冲过程和与之相关的滨海大断裂的运动学性质是密切相关的,即瓯江凹陷的构造演化及成盆过程受滨海大断裂的运动学性质控制,表现出张扭型盆地的特征。而距离滨海大断裂较远的闽江凹陷和基隆凹陷则主要受俯冲带后撤导致的拉伸作用的影响,具有伸展型盆地的特征。中生代盆地的演化过程如下:在晚侏罗世,滨海大断裂表现为右行压扭性质,由于受到俯冲作用的影响,整个盆地在该期应属于压扭性的盆地;晚侏罗世—早白垩世早期,滨海大断裂由晚侏罗世的右行走滑转换为左行走滑,诱导出NW—SE向的拉伸力,同时,瓯江凹陷与闽江、基隆凹陷的性质产生分异;早白垩世晚期—晚白垩世,滨海大断裂再次转换为右行张扭,由此瓯江凹陷在原右阶雁列式排列的两个洼陷基础上,形成了3个左阶雁列式排列的次级洼陷,同时,受断层控制的雁荡低凸起逐渐形成,并被一条NW—SE走向的断层分割,使得雁荡低凸起呈雁列式不连续分布。
The convergence of the East China Sea Shelf Basin in the Eurasian Plate, the Pacific Plate and the Philippine Sea Plate is one of the key areas for studying the transformation of the global structural system. The Mesozoic combination and evolution process of several tectonic units in Oujiang Sag, Yandang Low Protuberance, Minjiang Sag, Taipei Low Protuberance and Keelung Depression in the southern East China Sea Shelf Basin were simulated by physical sandbox experiment. It is found that the Mesozoic process and properties of the Mesozoic in the East China Sea Shelf Basin are closely related to the subduction process of the Isenginazaki plate in the Mesozoic Era and the kinematical properties of the major coastal faults related to it, that is, tectonic evolution and basin formation in the Oujiang Sag The process is governed by the kinematic properties of the major coastal faults and shows the characteristics of the Zhangshui basin. While the Minjiang sag and Keelung sag far away from the large coastal fault are mainly affected by the stretching caused by the subduction zone retreat and have the characteristics of extensional basins. The evolution of the Mesozoic basin is as follows: In the Late Jurassic, the large margin of the coast is characterized by right-lateral compressive-torsional deformation. Due to the subduction, the whole basin should belong to the pressure-stress basin during this period. Late Jurassic- In the early Cretaceous, the large coastal fault changed from the right-lateral slip to the left-slip in the Late Jurassic to induce the NW-SE tensile force. At the same time, the nature of the Oujiang Depression and the Minjiang River and the Keelung Depression were differentiated. From the Early Early Cretaceous to the Late Cretaceous, the large coastal fault again transforms to a right-lateral twist. Based on the two depressions of the original right-order geese in the Oujiang Sag, three left- At the same time, the Yandang low bump controlled by the fault gradually formed and was divided by an NW-SE fault to make the low-lying YanDang bursts appear in an echelon discontiguous distribution.