再论川西坳陷须家河组二段气藏地震相特征

Re-discussion on seismic facies characteristics of the 2nd member of Xujiahe Formation in Western Sichuan Depression

(1.成都理工大学能源学院,四川成都 610059;2.中国石油化工股份有限公司西南分公司,四川德阳 618000)

Energy faculty,Chengdu University of Technology,Chengdu 610059,China

川西坳陷深层须家河组二段蕴含着丰富的天然气资源,但储层致密化严重,成藏机理复杂,气藏以岩性和成岩圈闭为主,具有较大的隐蔽性,勘探难度大，有利目标预测困难。为此,通过分析层序地层格架、地震相及有利沉积相分布特征,结合裂缝预测技术,预测和描述油气富集带。研究结果表明,新场地区和大邑地区的须家河组二段河口坝及其下方的前缘砂体顶部为有利油气富集相带,是最有利的勘探目标区。根据预测结果,在德阳向斜部署了一口探井。

The 2nd member of Tertiary Xujiahe Formation is characterized by huge natural gas resource,serious densification degree of reservoir,complex pooling mechanism.Gas reservoir is mainly of lithology subtle trap,it is difficult for seismic exploration and beneficial target prediction.Therefore,by analyzing sequence stratigraphic framework,seismic facies and favorable sedimentary facies,combing with fracture prediction technology,the hydrocarbon bearing belt was fine described.The result shows that the mouth bar and underlying frontier sandbodies top of the 2nd member of Tertiary Xujiahe Formation in Xinchang area and Dayi area are favorable hydrocarbon accumulation belt,which is the favorable exploration target.In terms of prediction result,one exploration well was deployed in Deyang Syncline.