Title

Phase velocity analysis of multi-channel transient surface wave

单位

(1.西安石油大学地球科学与工程学院,陕西西安710065;2.Mewbourne College of Earth and Energy,University of Oklahoma,Norman Oklahoma 73019,USA;3.长安大学地质工程与测绘工程学院,陕西西安710054;4.中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000)

Organization

(1.School of Earth Sciences and Engineering,Xian Shiyou University,Xian 710065,China;2.Mewbourne College of Earth and Energy,University of Oklahoma,Norman Oklahoma 73019,USA;3.College of Geology Engineering and Geometics,Changan University,Xi’an 710054,China;4.Institute of Geophysical & Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China)

摘要

提取相速度是面波数据处理的核心内容之一,其准确程度将直接影响到面波勘探的成效。借鉴传统反射波速度分析方法的思想,基于二维傅里叶变换理论,通过深入分析相速度(v_R)与频率(f)、波数(k)之间的关系以及面波有效探测深度(h)与波长(λ_R)之间的关系,建立了多道瞬态面波相速度分析方程组,然后将实测多道瞬态面波的f-k谱转换成面波相速度分析谱(h- v_R谱),并建立了多道瞬态面波相速度分析处理流程,最终形成了一套有效的多道瞬态面波相速度分析方法。理论模型数据处理结果验证了该方法的有效性,并将其应用于反射地震资料中的瑞雷面波处理。与传统f-k方法的处理结果相比较,该方法不但能有效提取面波相速度参数,而且相速度与深度对应直观,可直接用于解决实际地质问题。

Abstract

Phase velocity extraction is one of the core steps of surface wave data processing,and its accuracy will directly affect the results of surface wave survey.Inspired by the idea of the conventional reflection wave velocity analysis method,and on the basis of 2D Fourier transform theory,the relationship among the phase velocity (vR),frequency (f) and wave number (k) as well as the relationship between the effective penetration depth (h) and wavelength (λR) of surface wave were analyzed,and the equations for phase velocity analysis of multi-channel transient surface wave were built.Then,the measured f-k spectrum of multi-channel transient surface wave was transformed into phase velocity analysis spectrum (h- vR spectrum),and the processing workflow for velocity analysis of multi-channel transient surface wave was established.Finally,a set of effective phase velocity analysis methods of multi-channel transient surface wave was formed.Theoretical model testing results prove the effectiveness of the method.Moreover,the method is applied to the processing of Rayleigh wave in reflection seismic data.The results show that the method can effectively extract the phase velocity parameters of surface wave,and the variation of phase velocity versus depth is intuitive,which can be directly used to solve geological problem.

关键词：

面波; 反射波; 二维傅里叶变换; 相速度分析; 近地表结构;

Keywords:

surface wave,; reflection wave,; 2D Fourier transform,; phase velocity analysis,; near-surface geological structure;

基金项目

国家自然科学基金(41374145)、中石油科技创新基金项目(2010D-5006-0303,2014D-5006-0303)和陕西省教育厅重点实验室科研计划项目(13JS093)联合资助。

DOI

10.3969/j.issn.1000-1441.2016.05.008