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通过在天山地区布设宽频带数字流动台阵, 利用观测获得的远震体波波形资料, 采用接收函数方法, 得到天山造山带和塔里木盆地北缘结合部 0~80 km 深度范围的二维 S 波速度剖面. 研究结果表明: 研究区域的地壳上地幔速度结构存在显著的垂向和横向变化, 垂向速度结构存在 4 个速度界面, 其中结晶地壳可分为上中下三部分, 中上地壳内普遍存在低速层. Moho 界面深度变化范围在 42~52 km,在剖面北端存在 4~6 km 错动, 北深南浅, 显示出向北俯冲的态势, 推测为塔里木向天山下俯冲的前沿.Moho 界面在塔里木盆地北缘表现为一级速度间断面, 库尔勒以北主要表现为速度梯度带. 通过地壳上地幔精细速度结构和深部盆山接触变形关系研究, 揭示了天山-塔里木盆山接合部南北向挤压变形增厚的动力学特征, 为建立盆山耦合大陆动力学模型提供基础依据.
Through the deployment of broadband digital mobile array in the Tianshan area and the use of teleseismic body waveform data obtained by observation, the two-dimensional S-wave of 0-80 km depth in the junction of the Tianshan orogenic belt and the northern margin of the Tarim Basin was obtained by using the receiver function method Velocity profile.The results show that the velocity structure of the crust and upper mantle in the study area has significant vertical and horizontal variations, and there are four velocity interfaces in the vertical velocity structure, in which the crystalline crust can be divided into three parts: upper and lower crust, middle-upper crust And the low-velocity layer is widespread.The range of Moho interface varies from 42 km to 52 km, with a range of 4 km to 6 km at the northern end of the profile and a north-south-shallow subduction pattern, indicating a northward subduction trend, presumed to be the front of the Tarim subduction to the Tianshan Mountains. The interface is characterized by a first-order velocity discontinuity in the northern margin of Tarim Basin and a velocity gradient zone in the north of Korla.Through the study of the relationship between the fine velocity structure of the crust and upper mantle and the contact deformation in deep basin-mountain, The dynamic characteristics of the pressure deformation and thickening provide the basis for establishing the basin-mountain coupling continental dynamic model.