渝东鄂西地区志留系盆地沉积充填及储层发育特征  

The Characteristics of Sedimentary and Packing and Reserves Development for Silurian Basin in the East Chongqing and West Hubei Area

作　　者：杨振武[1] 纪凡[1] 

机构地区：[1]江汉油田分公司勘探开发研究院,湖北潜江433124

出　　处：《石油天然气学报》2009年第4期166-169,共4页Journal of Oil and Gas Technology

摘　　要：四川盆地渝东鄂西地区志留系盆地沉积经历了4个演化阶段:龙马溪早期前陆坳陷盆地阶段、龙马溪晚期-小河坝早期隆后坳陷发展阶段、小河坝晚期-韩家店期坳陷充填阶段、秀山组-回星哨时期发展阶段,首次提出小河坝组砂岩为潮控浅水陆棚潮汐沙波沉积,韩家店组为潮坪沉积。通过不同界面性质的序列转换,确定鄂西渝东地区中、下志留统可划分出4个三级层序SSQ1、SSQ2、SSQ3和SSQ4。研究表明,受多方向陆源碎屑供给的控制,区内中、下志留统发育多套低孔、低渗致密砂岩储层,以裂缝系统沟通。纵向上不同的沉积层序决定砂岩发育部位,沉积相带控制储层分布范围,储层发育具有不同的特点。区内志留系广泛发育,应具有较好的勘探前景。The depositional evolution of Silurian Basin had undergone 4 stages:foreland depressional basin in early S1l,lifted depressional development at late S1l-early S1x,depressional packing at late S1x -S2h,depositional devolopment in S2x-S2hx in east Chongqing and west Hubei Area of Sichuan Basin.It was first revealed that the sandstones of S1x are shallow continent shelf tidal sand wave deposition controlled by tide,and the sandstones of S2h are tidal flat deposition.Due to succession changes of different surfaces,four 3rd sequences can be defined,such as SSQ1,SSQ2,SSQ3 and SSQ4.It is found from this study that there are sets of reservoirs with small porosity and low permeability,under the control of clasts supply from different directional provenances,specially linked up with the different fracture systems.The sandstone reservoirs are developed with different features,vertical positions are established by different depositional sequences,and their lateral distribution is controlled by the sedimentary facies belts.There are great prospects of exploration for the regional distribution of the Silurian formations in the study area.

关 键 词：四川盆地 志留系 沉积充填 储层 砂岩 

分 类 号：P618.13[天文地球—矿床学]