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中国东部海域(东海、黄海、渤海)濒临西太平洋,绝大部分为水深小于200米的浅海陆架区,只东南部冲绳海槽为水深2000多米的半深海区。 一、中国东部海域的构造分区 渤海,黄海坐落于中朝古陆陆壳内部,海区基底为前古生代变质岩系,大致相当于陆上的泰山群、朐山群和朝鲜的太白群。中生代构造断裂活动使陆壳解体成块状结构,各块体的差异性运动,形成分割的沉降盆地,其基底最大埋藏深度达7—9公里。其上沉积了巨厚的中、新生代地层,主要是陆相碎屑岩,夹海相层,更新世为海陆交互相沉积。玉木冰期后,海平面上升,海水全面覆盖渤海、黄海区,为浅海相沉积。因此,渤海和黄海乃是欧亚板块内部由断陷形成的海区,称之为陆陷海区。 东海可分为两部分,一部分是陆架浅海区,另一部分是冲绳海槽半深海区。陆架浅海区水深在200米以内,地形平坦,是中国大陆向东海的自然延伸。其磁场特征与相邻的
The eastern waters of China (the East China Sea, the Yellow Sea and the Bohai Sea) are close to the western Pacific Ocean, with the vast majority of shallow sea shelf areas of less than 200 meters in depth. The southeastern part of the Okinawa Trough is a semi-deep sea area of more than 2,000 meters. First, the structural division of eastern China Sea Bohai Sea, the Yellow Sea is located in the Sino-Northwestern continental crust, the basement of the former Paleozoic metamorphic rocks, roughly equivalent to the onshore Taishan, Dangshan and North Korea Taibai. The Mesozoic tectonic faulting led to the disintegration of the continental crust into a massive structure and the differential movement of various blocks to form a divided subsidence basin with a maximum buried depth of 7-9 km. On the deposition of a huge thick Mesozoic and Cenozoic strata, mainly continental clastic rocks, the folder of the marine phase, the Pleistocene for the sea-land interaction facies deposition. Tamaki ice period, the sea level rise, the sea water coverage of the Bohai Sea, the Yellow Sea, shallow marine sediments. Therefore, the Bohai Sea and the Yellow Sea are the sea areas formed by the fault depression in the Eurasian Plate, which is called the land-locked sea area. The East China Sea can be divided into two parts, one part is the shallow shelf on the shelf and the other is the semi-deep sea on the Okinawa Trough. Shallow shallow water depths within 200 meters, flat terrain, is the natural extension of the Chinese mainland to the East China Sea. Its magnetic field characteristics and the adjacent