逆时偏移与Kirchhoff偏移的对比研究

发布时间：2018-03-05 10:51

本文选题：逆时偏移　切入点：Kirchhoff偏移　出处：《地球物理学进展》2017年02期 　论文类型：期刊论文

【摘要】：Kirchhoff偏移和逆时偏移(RTM)是目前最广泛应用的两种叠前深度偏移方法.两种方法的基础均为波动方程,理论上没有倾角限制.抽取的共成像点道集(CIG)可用于速度建模、叠前反演以及地下属性解释等.叠前反演的精度依赖于共成像点道集的AVO特性是否符合地下介质的真实地震响应.因此,叠前偏移不仅要实现反射点的准确归位,得到的共成像点道集必须要振幅保真.本文在理论上阐述两种偏移方法的基本原理,并对抽道集技术的保幅性进行对比.Marmousi和Sigsbee2a模型结果表明:在简单构造区,两者的成像效果相当;在复杂构造区,不论在成像精度还是保幅性上逆时偏移都比Kirchhoff偏移优越,特别是高陡倾角断层、岩下构造等复杂构造成像时.然而,在碳酸盐岩储层实际资料处理时发现,由于速度场准确性的限制,两种偏移方法各有优势.因此,在实际应用时,由于无法明确得到地下介质的确切信息,较难对两种偏移方法给出明确的优劣评价.
[Abstract]:Kirchhoff migration and inverse time migration are two kinds of prestack depth migration methods which are widely used at present. Both methods are based on wave equation and have no inclination restriction theoretically. The extracted common imaging point gathers can be used for velocity modeling. The accuracy of prestack inversion depends on whether the AVO characteristics of the common imaging point gathers accord with the true seismic response of underground media. The obtained common imaging point gathers must be amplitude fidelity. In this paper, the basic principle of the two migration methods is described theoretically, and the comparison of the amplitude-preserving properties of the extraction gather technique with the Sigsbee2a model shows that: in the simple structural region, In complex structural areas, the imaging accuracy and amplitude-preserving inverse migration are superior to Kirchhoff migration, especially for complex structures such as high-steep dip faults and subrock structures. When processing the actual data of carbonate reservoir, it is found that due to the limitation of the accuracy of velocity field, the two migration methods have their own advantages. Therefore, in practical application, the exact information of underground media can not be clearly obtained. It is difficult to give a clear evaluation of the two migration methods.
【作者单位】：中国石油大学胜利学院油气工程学院;中国石油大学地球科学与技术学院;
【基金】：国家自然科学基金青年基金项目(41104069) 中国石油大学胜利学院春晖计划项目(KY2015003)联合资助
【分类号】：P631.44

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