单事件频域接收函数计算云南地壳厚度与泊松比

发布时间：2018-03-20 01:39

本文选题：接收函数　切入点：频率域　出处：《云南大学》2015年硕士论文　论文类型：学位论文

【摘要】：接收函数是目前比较流行,非常有力的研究地壳和上地幔的工具。其基本原理是通过反褶积将复杂的远震体波转换成尖脉冲,从而方便精确地识别转换波的到时。因此接收函数类似于数学中的格林函数。然而国内现在的接收函数程序大多从国外引进,本文的一个重要动机就是独立自主地编制频域的接收函数并进行测试。从接收函数的运用来讲,主要集中在多事件叠加,很少运用单事件计算。多事件叠加的优点在于能去除干扰和噪声,缺点是必须事先利用一个参考模型来动校正。由于参考模型未必反映研究区域的真实模型,动校正会有误差,导致多事件叠加的波形失真。因此,本文采取单事件来研究,相应的缺点是震相识别有一定困难。云南地处青藏高原东南缘,是古特提斯洋东缘地带,地震频发,地质情况复杂,是研究陆陆碰撞的天然理想场地。我们用接收函数获取了云南地壳厚度和泊松比。结果表明：云南地区的Moho面深度与地表海拔具有的相关性,总体呈北厚南薄的特点,可以用重力均衡理论加以解释。云南的三个火山区表现出高泊松比,在物理上是合理的。与四川盆地相邻地区,泊松比较低。沿红河断裂分布三个高泊松比区,证明了该断裂具有流变特性。
[Abstract]:The receiving function is a popular and powerful tool for studying the crust and upper mantle. Its basic principle is to convert complex teleseismic body waves into sharp pulses by deconvolution. Therefore, the receiving function is similar to the Green's function in mathematics. However, most of the current domestic receiving function programs are imported from abroad. An important motivation of this paper is to independently compile and test the frequency domain reception function. In terms of the application of the receiving function, it is mainly concentrated in the multi-event superposition, and the single event calculation is seldom used. The advantage of the multi-event superposition is that it can remove the interference and noise. The drawback is that a reference model must be used for NMO correction in advance. Because the reference model does not necessarily reflect the real model of the study area, the NMO will have errors, resulting in the waveform distortion of multi-event superposition. The corresponding drawback is that it is difficult to identify the seismic phase. Yunnan is located in the southeastern margin of the Qinghai-Tibet Plateau. It is the eastern margin of the ancient Tethys, with frequent earthquakes and complicated geological conditions. The results show that the depth of the Moho surface in Yunnan is correlated with the elevation of the surface, and the thickness of the crust is thin in the north. It can be explained by the theory of gravity equilibrium. The three hot mountain areas in Yunnan show high Poisson ratio, which is reasonable in physics. Poisson is relatively low in the adjacent area of Sichuan Basin, and distributes in three high Poisson ratio areas along the Red River fault. It is proved that the fracture has rheological properties.
【学位授予单位】：云南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P315.2

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