Ultra efficient methods for modelling waveforms in seismic surveys

地震勘探中波形建模的超高效方法

• 批准号: 13640425
• 负责人: TAKENAKA Hiroshi
• 金额: $ 1.02万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640425/
• 关键词: seismic exploration; elastic wave; seismic waveform; FDTD; 2.5-D; wave computation; plane wave; 人工地震質探査; 弾性波動; 地質波形; 1次元構造; 地震波; スタガード格子

In this study we developed efficient numerical methods for modeling seismic waveforms in seismic exploration.In the first year we developed a very efficient procedure to calculate plane-wave responses of arbitrary 1-D media, such as gradient velocity or randomly heterogeneous structures, using the finite-difference method in the time domain (FDTD). This may be useful for analysis of reflection survey or seismic logging data.In the second year we developed an ultra efficient method for modeling seismic waveforms in refraction or wide-angle reflection surveys. The most common form of seismic exploration remains a nearly linear survey with data acquisition lines including the source and receivers. For this situation we developed a 2.5-D modeling method for the simulation of 3-D seismic wavefields in media varying in two dimensions. The computer memory requirements and computation time are only slightly larger than those for 2D computations. We demonstrated the validity and efficiency of the technique with numerical examples, including a profile across a realistic model of subduction zone structure.

在这项研究中，我们开发了一种有效的数值方法来模拟地震勘探中的地震波形。在第一年，我们开发了一个非常有效的程序来计算平面波响应的任意一维介质，如梯度速度或随机非均匀结构，在时域有限差分法（FDTD）。这可能对反射勘探或地震测井数据的分析很有用。第二年，我们开发了一种超高效的方法，用于折射或广角反射勘探中的地震波形建模。地震勘探最常见的形式仍然是一种接近线性的勘探，其数据采集线包括震源和接收器。针对这种情况，我们提出了一种二维介质中三维地震波场的2.5维模拟方法。计算机内存需求和计算时间仅略大于2D计算。我们证明了该技术的有效性和效率的数值例子，包括一个剖面横跨一个现实的模型俯冲带结构。

项目成果

H.Takenaka, H.Tanaka, T.Okamoto, B.L.N.Kennett: "Quasi-cylindrical 2.5D wave modeling for large-scale seismic surveys"Giophysical Research Letters. Vol.30,No.21. doi:10.1029/2003GL018068 (2003)

H.Takenaka、H.Tanaka、T.Okamoto、B.L.N.Kennett：“大规模地震勘测的准圆柱 2.5D 波建模”地球物理研究快报。