叠前频散属性在琼东南盆地油气检测中的应用  

Study and application of prestack dispersion attribute in hydrocarbon detection in Qiongdongnan basin

作　　者：孙万元 胡林 陈殿元 刘仕友 汪锐 廖键 SUN Wanyuan;HU Lin;CHEN Dianyuan;LIU Shiyou;WANG Rui;LIAO Jian(Zhanjiang Branch Company of China National Offshore Oil Corporation, Zhanjiang 524000, China)

机构地区：[1]中海石油(中国)有限公司湛江分公司,湛江524000

出　　处：《物探化探计算技术》2020年第5期623-628,共6页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：“十三五”国家科技重大专项(2016ZX05026-002,2016ZX05024-005)。

摘　　要：琼东南盆地L探区水深远超500 m,且水深变化幅度大,同时在目的层发育高温高压地层。受水深剧烈变化影响,地震振幅的横向变化导致该区块储层预测和烃类检测存在较大难度。高温高压岩石物理实验证明,高温高压条件下含流体砂岩在地震频段存在速度频散特征,这为基于频散理论进行流体检测提供了依据;由于双相介质理论可以很好地模拟孔隙流体与岩石骨架的地质特征,探讨频散理论进行油气检测可能性;基于Wigner分布的时频分析算法可以精准时频分析,为频散属性的提取提供了技术手段。根据双相介质理论提出频散属性算法,将该算法应用到南海琼东南盆地L探区,分析振幅差异较大的情况下频散属性差异,证明该区含气性,后经钻井证实该方法技术的有效性,并为后续提供新的勘探方向。The water depth exploration in L area of Qiongdongnan basin is far beyond 500m.At the same time,geophysical evaluation is difficult due to high temperature and high pressure formations developed in the target area.The lateral variation of seismic amplitude causes much difficulty in reservoir prediction and hydrocarbon detection in this block.Petrophysical experiments show that there exists velocity dispersion in high temperature and high pressure fluid sandstone in seismic frequency band,which provides a basis for fluid detection based on dispersion theory.Dual-phase medium theory can well simulate the geological characteristics of pore fluid and rock skeleton providing a theoretical basis for oil and gas detection based on dispersion theory.Time-frequency analysis algorithm based on Wigner distribution can precisely analyze time-frequency,which provides a technical means for the extraction of dispersion attributes.In this paper a dispersion property algorithm is proposed Based on the theory of two-phase media.The technology is applied to the L area of the Qiongdongnan basin,south China Sea.The difference of dispersion property under the condition of large amplitude difference is analyzed to prove the gas bearing property in this area.The validity of the method is verified by drilling.

关 键 词：频散 双相介质 高温高压 烃类检测 琼东南深水 

分 类 号：P631.4[天文地球—地质矿产勘探]