东海及邻近地区岩石圈三维结构研究

文中首先对两条剖面的岩石圈结构进行了论述。以两条剖面的岩石圈结构作为约束,采用小波分解、全磁纬变倾角化极和地热场反演岩石圈底界等项技术,获取了研究区沉积基底面、莫霍面和岩石圈底界面在三维空间的展布以及岩浆岩的分布。在此基础上论述了岩石圈各层的展布及岩石圈三维结构单元的划分,认为东海陆架盆地的东部凹陷带为寻找油气最有利的地区,冲绳海槽为弧后盆地,钓鱼岛岩浆岩带为中酸性岩浆岩带,吐嘎喇火山带为当今火山弧,琉球岛弧为欧亚板块裂离部分,琉球岛弧东部斜坡为古东海大陆架的陆坡,位于此陆坡上的凹陷为弧前盆地。

A STUDY ON LITHOSPHERE 3D STRUCTURES IN THE EAST CHINA SEA AND ADJACENT REGIONS

Based on the geophysical data from two profiles, the lithosphere structures of the East China Sea and neighboring areas were discussed. Using wavelet analysis, reduction to pole about all magnetic? T anomalies by varied dips at any latitudes, lithosphere bottom inversion by the geothermal field etc., according as the structures of two profiles, 3d distribution of the sedimentary basement, Moho surface, the lithosphere bottom and distribution of magmatic rocks were obtained. On the basis, the distribution of stratum and partition of 3d lithosphere structural units were divided. The shelf of the East China Sea was a beneficial region for oil and gas exploration. The following opinions were emphasized in the paper: the Okinawa trough being a back-arc basin, the Tiaoyu Island magmatic belt consisting of inetrmediate-acidic magmatic rocks, the Tokara volcanic belt representing a modern island arc, the formerly called "Ryukyu Islands Arc" being a part drifted from the Eurasian plate, and the east slope of the "Ryukyu Islands Arc" being, correspondingly, a continental slope on paleo-shelf of the East China Sea, and the depressions on the slope being fore-arc basins.