应用边界元模拟方法分析复杂海底地震散射特征  

Analysing seismic scattering characteristics of complex seabed by using the boundary-element simulation method

作　　者：李绪宣 于更新[2] 符力耘[2] 温书亮 管西竹[2] 

机构地区：[1]中海油研究总院 [2]中国科学院地质与地球物理研究所

出　　处：《中国海上油气》2011年第6期357-361,368,共6页China Offshore Oil and Gas

基　　金：国家重点基础研究计划(973计划)项目"南海深水区复杂地质结构地震采集基础理论研究(2009CB219403)"资助部分研究成果

摘　　要：边界元法对随机起伏的复杂海底界面具有良好的适应性。比较了边界元法与有限差分法对复杂断层模型的模拟精度,并验证了边界元法的有效性。利用边界元法对复杂海底模型进行波场模拟,反映起伏海底界面对地震波传播的影响;利用统计参数描述复杂海底地貌特征,将崎岖海底界面划分为快、慢变化和强、弱起伏等4种特征类型。根据不同统计参数的选择建立崎岖海底理论模型,利用边界元法对不同类型的崎岖海底理论模型进行模拟研究,同时与实际海底资料相对比,分析了复杂海底地震散射特征。此项研究成果可为复杂海底地区目标导向地震观测系统设计和采集参数优化提供理论依据。The boundary-element method （BEM） has a good adaptability for simulating irregularly rough and complex seabed. The simulation accuracy of BEM for a complex fault model was compared with that of the finite-difference method, and the effectiveness of BEM was confirmed. BEM can be used to conduct wave simulation of rough seabed models, reflecting the impacts of rough seabed on seismic wave propagation. The statistical parameters were used to describe complex seabed topogra phy, and then four types of rough seabed interface can be identified, i. e. fast lateral eral change, strong vertical relief change, slow latand weak vertical relief. The theoretical models of rough seabed can be build by selecting various statistical parameters, and BEM was used to make simulation of different theoretical models of rough seabed. Simultaneous ly, some actual seabed data was compared and the seismic scattering characteristics of complex seabed were analyzed. These results will provide some theoretical foundations for the seismic acquisition design of complex seabed and the optimization of seismic acquisition parameters.

关 键 词：边界元法 复杂海底 地震波传播 散射特征 

分 类 号：P738.4[天文地球—海洋地质]