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台湾海峡及邻区地处欧亚板块与菲律宾海板块相互作用的构造前锋部位,经历了挤压、剪切和伸展交替或并重的构造作用,这种复杂应力环境下岩石圈的均衡调整对台湾地区的构造演化具有深远影响.通过采用均衡响应函数法计算穿越台湾海峡及邻区剖面岩石圈的有效弹性厚度,利用剥离法消除台湾海峡及东邻岛区较厚沉积层的影响,得到了穿越台湾海峡地区剖面岩石圈弹性厚度的变化.结合反演的莫霍面和居里面深度对剖面有效弹性厚度的构造意义进行了综合分析.结果表明:台湾海峡及邻区岩石圈有效弹性厚度变化范围为22~8km,剖面有效弹性厚度整体上自西往东呈楔形递减趋势,反映中国东部大陆岩石圈往东伸展减薄;台湾岛附近有效弹性厚度出现局部向东倾斜增大的趋势,可能与东侧菲律宾海板块的仰冲挤压有关.有效弹性厚度与居里面具有较高相关性,反映了有效弹性厚度受岩石圈热结构的影响.
The Taiwan Strait and its adjacent tectonic front located in the interaction between the Eurasian Plate and the Philippine Sea Plate have undergone tectonism of alternating compressional, shear and extensional changes. The balanced adjustment of the lithosphere under such complex stress conditions is of great significance to Taiwan Regional tectonic evolution has a far-reaching impact.By using the equilibrium response function method to calculate the effective elastic thickness of the lithosphere across the Taiwan Strait and its adjacent areas, using the stripping method to eliminate the influence of the thick sediments in the Taiwan Strait and the adjacent islands, The changes of elastic thickness of lithosphere in the cross section of the Taiwan Strait are analyzed.The structural significance of the effective elastic thickness of the section is analyzed by combining the inverted Moho and depth of interior.The results show that the effective elastic thickness range of the lithosphere in the Taiwan Strait and its adjacent area The effective elastic thickness of the section decreases gradually from west to east as a wedge, reflecting that the east China lithosphere extends eastward thinning; the effective elastic thickness near Taiwan Island tends to increase locally eastward, which may be related to On the east side of the Philippine Sea plate Yangsheng extrusion related to effective elastic thickness and in-house has a high correlation, reflecting Effect of Heat Structure thickness under the effective elastic rock.