岩石物理模型在横波速度估算中的应用

Application of rock physical model in S-wave velocity estimation

(中国石油化工股份有限公司上海海洋油气分公司研究院,上海200120)

Xie Yuefang,Institute of Sinopec Shanghai Offshore Oil & Gas Branch Company,Shanghai 200120,China

岩石物理模型是进行岩石物理研究、求取横波速度的重要基础。利用Xu-White砂泥岩混合模型,通过岩心测试数据、纵波和密度曲线、泥质百分含量及孔隙度测量得到岩石骨架的体积模量和剪切模量,然后计算不同流体及流体饱和度下岩石的有效弹性模量,进而计算出纵、横波速度。经过与实测密度、纵波资料的对比,调整参数循环迭代计算,得到最终横波速度。利用岩石物理模型估算横波速度,解决了平湖油气田放鹤亭构造常规测井缺乏横波资料的难题,为AVO正演模拟、叠前AVO/AVA同步反演提供了可靠的基础数据。

Rock physical model is an important basis of petrophysical research and S-wave velocity estimation.Based on Xu-White sand-clay mixed model,by using core testing data,P-wave and density log,clay content and porosity measurement,we calculated bulk and shear modulus of dry rock;then,the effective elastic modulus in different fluids with different saturation was calculated;finally,the P-wave velocity and S-wave velocity were computed.By comparison with actual density and P-wave data,we constantly modified parameters and carried out iterative computation.By this means,the S-wave velocity can be obtained.Through S-wave velocity estimation by using rock physical model,the problem of missing S-wave data in conventional logging data of Fangheting structure in Pinghu Gasfield was solved,which provided reliable basic data for AVP forward modeling and pre-stack AVO/AVA simultaneous inversion.

10.3969/j.issn.1000-1441.2012.01.009