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综合地震层析成像与重磁数据的处理结果,选择26°N～36°N,120°E～130°E的范围作为研究区,讨论了黄、东海研究区的深部结构特点及其与周边各地质单元的相互关系,完成了研究区两条剖面的密度结构反演,认为东海陆架地区地壳厚度变化与大陆地区相比并不明显,显著减薄开始于冲绳海槽地区,中地壳消失;琉球岛弧处地壳厚度明显再度增加,特别是上地壳的厚度增加最大,推断其原因应与俯冲作用及俯冲带附近板块与地幔的运动速率之差有关.地球物理场“东西分带”是黄海—东海地区壳内结构从西向东变化的反映,但随着深度的增加,研究区的岩石层结构出现以近EW向为优势的构造格局.因此推断深部近EW向的异常是三叠纪时期南北板块碰撞、挤压所致,浅部的NE向条带异常是后期构造运动在岩石层较浅部位构造效应的反映.黄海—东海地区岩石层结构存在浅部与深部优势构造方向不协调的现象.层析成像结果证实了南黄海东缘断层的存在,还勾绘出绍兴—十万大山碰撞带为以40°左右的倾角向NW方向倾斜的高速带,另一条倾向基本相同的高速带则是南、北扬子块体结合带在深部的反映.
Based on the results of comprehensive seismic tomography and gravity and magnetism data processing, the range of 26 ° N ~ 36 ° N and 120 ° E ~ 130 ° E is selected as the study area, and the deep structural features of the study area in the Yellow Sea and East China Sea, The inversion of the density structure of the two sections of the study area completed the correlation of the geologic units. It is concluded that the crustal thickness changes in the East China Sea continental shelf are not obvious compared with those in the continental area. The significant thinning begins in the Okinawa Trough and disappears in the middle crust. The thickness of the crust at the Ryukyu Island arc obviously increased again, especially the increase of the thickness of the upper crust, which is supposed to be related to the subduction and the difference between the velocity of the plate and the mantle near the subduction zone. - The reflection of the intra-crustal structure in the East China Sea from west to east, but with the increase of depth, the structure of the lithosphere in the study area is predominant near EW direction. Plate collision and crustal crustal anomaly is the reflection of the tectonic effect of later tectonic movement in the shallow parts of the rock strata.The NE of the Yellow Sea - The results of tomographic imaging confirmed the existence of faults in the eastern margin of the southern Yellow Sea and also delineated the high-speed zone in the collision zone of Shaoxing-Shimenshan Dadongshan inclined to the NW at an inclination of about 40 ° A tendency of basically the same high-speed zone is the South, North Yangtze block with the reflection of the deep.