摘要
苏里格气田属于我国特大型气田之一,地震反演技术广泛应用在气田勘探开发阶段.对研究区已有的资料进行岩石物理分析发现,纵波阻抗不能够识别目的层段砂岩、泥岩以及含气层.为了克服这一困难,采用叠前反演技术对盒_8-山_1段岩性气藏进行了刻画.在测井资料质控下以分角度叠加数据体作为输入,可以输出阻抗剖面以及纵横波速度比、泊松比等岩石弹性参数,综合判储层的岩性、物性及含气性.研究结果表明:(1)纵波阻抗不能区分砂泥岩以及含气砂岩,砂岩含气后,纵波阻抗明显降低,且分偏移距叠加数据体的振幅随偏移距的增加而增加,属于第三类AVO;(2)利用Xu-White模型对缺失横波资料进行反演,反演横波与全波测井实测横波对比发现相似度极高;(3)从反演结果来看,砂岩含气后横波阻抗不变,可以指示砂岩,速度比和泊松比显示异常小值,可以刻画含气砂岩.实钻证明,叠前反演技术为最终的井位优选和储层评价提供了可靠的依据.
Sulige gas field is one of the largest gas field in China and seismic inversion is widely used in the stage of gas field exploration and development. According to the rock physical analysis of the data in a study field, P-wave impedance can’t be used to identify the sandstone, mudstone of the target layer also the gas-bearing stratum. To overcome the difficulty, pre-stack inversion technology has been applied to describe lithologic gas reservoirs of the box8-shan1.Using the stacking data of different pre-stack angle as an input, quality controlled by logging data, impedance section, S-wave and P-wave velocity ratio, Poisson’s ratio and other elastic parameters of rock can be output to comprehensively identify reservoir lithology, physical property and whether has gas. The result of the study is:(1)P-wave impedance can not distinguish mudstone and gas-bearing sandstone. For gas bearing sandstone, P-wave impedance decreases obviously and the amplitudes of stack gathers with different pre-stack offset increase as the angle increases, which belongs to the third class AVO;(2)when performing inversion lacking of S-wave data with the Xu-White model, the similarity is high compared inversion of S-wave with the S-wave measured by full-wave logging;(3)from the results of inversion, the S-wave impedance of gas-bearing sandstone does not changed, which can indicate the sandstone, also the velocity ratio and Poisson’s ratio show abnormal small value, which can describe the gas-bearing sandstone. Above all, in the practical drilling, a reliable basis can be provided for the selection of wells and reservoir evaluation by pre-stack inversion.
作者
苏海
郑德德
高棒棒
何为
杜中东
赖生华
SU Hai;ZHENG De-de;GAO Bang-bang;HE Wei;DU Zhong-dong;LAI Sheng-hua(School of Earth Science And Engineering,Xi’an Shiyou University,Xi’an 710065,China;Exploration Department of Petroleum China Changqing Oilfield company,Xi’an 710018,China;Changqing Branch,Geological Research Institute,BGP,CNPC,Xi’an 710021,China)
出处
《地球物理学进展》
CSCD
北大核心
2019年第1期179-184,共6页
Progress in Geophysics
基金
国家自然科学基金项目(41372118)
西安石油大学研究生创新与实践能力培养项目(YCS16211015)联合资助
关键词
苏里格气田
叠前反演
波阻抗
第三类AVO
泊松比
Sulige gas field
Pre-stack seismic inversion
Elastic impedance
Third class AVO
Poisson’s ratio
