转换波多次分裂数值模拟与层剥离技术应用  

Application of fracture detection technique by converted wave splitting in multilayer fractured media

作　　者：程冰洁[1] 毛树林[2] 徐天吉[2,3] 

机构地区：[1]成都理工大学信息工程学院,四川成都610059 [2]成都理工大学能源学院,四川成都610059 [3]中石化西南分公司勘探开发研究院德阳分院,四川德阳618000

出　　处：《大庆石油学院学报》2010年第3期29-34,122-123,共6页Journal of Daqing Petroleum Institute

基　　金：成都理工大学人才引进科研项目(HL0066)

摘　　要：转换波分裂裂缝检测是多波多分量地震勘探的重要价值所在.根据转换波分裂的特点和信息,可以预测裂缝的发育方位和密度.在裂缝油气藏中,这2个参数对提高油气采集率具有重要意义.当研究的目标层以上的盖层中,存在不只一个含裂缝各向异性层时,转换波就会发生多次分裂,上覆各向异性对下层裂缝参数的计算具有较大影响,因此必须估算并补偿分裂的快慢波时差,消去盖层各向异性的影响,以获得更准确的目标层的裂缝信息.通过理论模型正演及实际资料计算分析,研究多层裂缝介质中转换波传播特征及分裂机制,分析转换波R,T分量在多层裂缝各向异性介质中的分裂特征,利用能量比法预测裂缝方位,估算快慢波时差,并做层剥离时差补偿后,提高计算精度.Robust and accurate estimates of fracture strike by PS waves splitting analysis is an important value of the multi-wave multi-component seismic prospecting.The converted wave retains the benefits of both P-and S-wave surveys,and offers more effective reservoir characterization and monitoring.The fracture strike and density can be estimated from splitting estimation and compensation of the converted wave.Polarity reversal points and time delay between fast and slow gathers are of great importance to improving the oil and gas acquisition rate in fractured oil and gas reservoirs.When the overburden over the target layer has more than one fracture anisotropic layers,the converted wave will split several times,and the anisotropy of the overburden stratum poses a considerable influence on the estimation of the fracture parameters in the target stratum.Therefore,the time delay between the fast and slow gathers must be estimated and compensated to eliminate the influence of the overlying stratum and acquire more accurate fracture information of the target stratum.By model simulation and application of real data,This paper studies converted waves propagation and splitting characters,analyzes the characteristics of R and T components of the converted wave splitting in the multilayer fracture anisotropic media,and uses the method of estimate the fracture strike,calculates the time delay between fast and slow gathers,and carries out the layer stripping and analyze the calculation precision of the method.

关 键 词：转换波 多层裂缝各向异性 裂缝检测 时差补偿 层剥离 

分 类 号：P631.4[天文地球—地质矿产勘探]