不整合面下隐伏逆冲断层反射地震成像模拟研究  

Reflection seismic modeling of a thrust fault under an unconformity interface

作　　者：原健龙 丘斌煌[1,2] 刘洪星[3] 周武[1] 余嘉顺[1] 

机构地区：[1]成都理工大学地球物理学院,成都610059 [2]中海油能源发展工程技术分公司物探技术研究所,湛江524057 [3]中国石油大学地球物理与信息工程学院,北京102249

出　　处：《物探化探计算技术》2015年第1期70-77,共8页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：中国地质调查项目(12120113095100);四川省科技厅科技支撑项目(2013SZ0173);国家级大学生创新创业训练计划(201310616003)

摘　　要：针对不整合界面下的逆冲断层进行反射地震勘探的可行性问题,进行了一项波动方程正演模拟数值试验。勘探的地质目标包括断层的断面形态,以及附近几个厚度仅仅为几米的地质透镜体。根据掌握的地质资料建立地震参数模型,用波动方程正演模拟技术模仿地震勘探观测系统的施工方式,滚动放炮合成了38炮地震数据,然后按照生产资料处理流程对这些数据进行处理,最后得到地震波速度模型剖面、地震数据叠加剖面以及偏移剖面等图像成果。试验结果表明,如果采用较高频率的震源信号,反射勘探地震成像方法可以有效地揭示不整合面下隐伏逆冲断层的空间展布形态,辨识地质透镜体存在。研究表明,选用主频为150Hz的高频率震源信号,可以使勘探达到最佳的分辨效果。A numerical experiment using seismic wave equation forward modeling was carried out to test the feasibility of re-flection seismic exploration of a thrust underlying an unconformity.The geological targets for the exploration include the fault and a few geological lenses as thin as only a few meters.Using the geological information available,a seismic model was built. Seismic wave equation forward modeling was then performed to mimic the approach of seismic acquisition.In total 38 shot gath-ers of seismic data were synthesized.Then data processing yielded a seismic velocity profiles,a CDP stack profile and a migra-tion profile.The experiment results show that,if high frequency source signals are used,seismic reflection exploration can ef-fectively reveal the thrust fault and the geological lenses.Our experiments show that using source signals with dominant fre-quency at 150Hz can achieve the best resolution.

关 键 词：逆冲断层 地震成像 正演模拟 数据处理 

分 类 号：P631.4[天文地球—地质矿产勘探]