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利用华南（包括台湾省）及其邻近地区地震台网记录到的５１４个区域地震和７１６个远震事件的１９７７７条Ｐ波到时数据，用地震层析反演方法重建了华南及其海域（１８．０°－３１．５°Ｎ，１０６．５°－１３０°Ｅ）的三维速度图像。结果表明：１．华南及其海域地壳和上地幔广泛存在显著的横向不均匀性，它不仅出现在海域和陆区不同构造之间，同时也出现在陆区不同构造单元之间及其内部．２．地壳上部速度图像呈现出陆区和海域的速度差异：海域表现为低速，陆区的大部分表现为高速，而地处陆缘海的长乐－南澳断裂带恰好对应于陆区高速和海域低速块体分界处。陆区的一些主要断裂带几乎都显示在速度梯度带上．３．１１０ｋｍ深度处的速度图像表明，华南海域普遍显示低速；陆区除东南沿海褶皱系和华南褶皱系西部为低速外，均为高速．说明海域和陆内活动区在这一深度处已有软流层显示。４．研究区域内岩石层厚度变化显著，在陆区，扬子准地台与较为活动的褶皱系相比，具有较厚的岩石层。华南褶皱系内部岩石层厚度也十分不同，其东北部岩石层厚度大于西南部，说明华南褶皱系内部活动程度不同，东北部相对稳定，西南部较为活动。台湾以东沿大陆架、大陆坡岩石层逐渐抬升，至海洋下方变得很薄，软流层顶部?
Based on 19777 P-wave arrival data of 514 regional earthquakes and 716 teleseismic events recorded by the seismological networks in South China (including Taiwan Province) and its adjacent areas, the seismic inversion method was used to reconstruct the data of South China and its sea areas 18.0 ° -31.5 ° N, 106.5 ° -130 ° E). The result shows: 1. There is widespread lateral inhomogeneity in the crust and upper mantle in the South China Sea and its sea area. It not only appears between different structures in the sea area and land area, but also between different structural units in the land area and its interior. 2. The velocity of the upper crust shows the velocity difference between the land area and the sea area: the sea area shows a low speed, most of the land area shows high speed, and the Changle-Nan’ao fault zone located in the marginal sea just corresponds to the low speed block Body boundaries. Nearly all of the major fault zones in the continental belt are shown on the velocity gradient. The velocity images at the depth of 3.110 km indicate that the South China Sea generally shows low speed. In addition to the southeast coastal fold series and the southern South China fold series, the continental belt is low velocity and high velocity. It shows that the sea area and intracontinental activity area have shown the asthenosphere at this depth. 4. In the study area, the thickness of rock layer varies significantly. In the continental area, the Yangtze platform has a thicker rock layer than the more active fold system. The thickness of rock layers in the South China fold system is also quite different, and the thickness of the lithosphere in the northeast is greater than that in the southwest, which shows that the South China fold system has different internal activities, the northeast is relatively stable and the southwest is relatively active. Along the continental shelf and the continental slope, east of Taiwan, the rock layers gradually rise up to the bottom of the ocean and become thin at the top of the asthenosphere.