弹性介质中一种多分量初至走时计算方法及数值模拟试验  

A computational method of a multi-component of elastic medium at the first arrival travel time and its numerical simulation experiment

作　　者：陈可洋[1] 许智禹[2] 范兴才[1] 吴清岭[1] 李来林[1] 关昕[1] 刘振宽 

机构地区：[1]中国石油大庆油田勘探开发研究院,黑龙江大庆163712 [2]中国石油大庆油田第一采油厂,黑龙江大庆163000 [3]中国石油大庆油田勘探分公司,黑龙江大庆163453

出　　处：《油气藏评价与开发》2013年第5期1-8,共8页Petroleum Reservoir Evaluation and Development

摘　　要：为了更好地研究多波多分量弹性波资料的精确深度域成像方法,采用高精度有限差分法推导了各向异性介质弹性波动方程正演数值模拟和逆时偏移成像的数值离散方程,给出了多分量弹性波联合初至走时模拟方法,开展了初至走时数值模拟试验研究。以均匀介质和层状介质模型为例,计算结果表明,由该方法计算的各向同性介质初至走时与相同速度模型情况下的解析解、声波最大振幅能量法计算的旅行时等值线以及对应多分量弹性波场快照叠合图基本重合,并将该方法应用于各向异性介质情况,计算结果均验证了所提方法的准确有效性。同时,以梯状各向异性介质模型为例,实现了多分量弹性波联合叠前逆时偏移,偏移结果较好地反映了速度模型的地质构造特征。In order to better study the accurate imagery method of multi-wave and multi-component elastic wave data in depth do-main, the forward numerical simulation of the anisotropic media elastic wave equation and the numerical dispersion equation of the reverse-time migration imagery were derived by high-precision finite difference method, a first arrival travel time simulation meth-od of multi-component elastic wave was proposed and the numerical simulation experiment was carried out. Taking uniform medi-um and layered medium as examples, the numerical results showed that the contour graphs of the first arrival travel time in the iso-tropic media calculated from this method. The analytical solution under the same velocity model and the travel time contour calcu-lated from maximum acousticwave amplitude energy method were almost overlapped. And it was also consistent with the multi-com-ponent elastic wave overlapped snapshots. When applied in the anisotropic medium, this method was verified to be accurate and ef-fective. Meanwhile, taking the ladder anisotropic medium model as an example, the reverse time migration of multi-component joint elastic wave was carried out. The migration results perfectly showed the model’s geologic characteristic.

关 键 词：弹性介质 初至走时 各向异性介质 各向同性介质 逆时成像条件 

分 类 号：TE132.14[石油与天然气工程—油气勘探]