准噶尔盆地红车地区侏罗系沉积特征与沉积环境演化

Sedimentary Characteristics and Environmental Changes of Jurassic in Hongche Area,Junggar Basin

红车地区侏罗系是准噶尔盆地西北缘重要的油气富集带之一,其沉积相的研究是有利区带评价的基础。首先结合测井、地震等资料,通过岩心描述和分析,在红车地区识别出冲积扇、辫状河、三角洲、湖泊等多种沉积相类型,其中八道湾组晚期及三工河组时期,振荡背景下形成辨状河三角洲前缘砂岩与滨浅湖泥岩交互沉积,生、储、盖配置关系良好,为岩性圈闭的有利相带。之后针对红车地区侏罗系主要地震相特征加以探讨,并在中期基准面旋回分析的基础上,明确侏罗系各砂组的沉积相平面展布特征,重塑红车地区侏罗纪沉积演化历史。最后探讨了沉积相与岩性圈闭发育的关系,并指出八道湾组及三工河组沉积时期岩性圈闭发育的有利位置。

Jurassic in Hongche area is one of the important petroleum zones.The study on the sedimentary facies of Jurassic is a foundation work for exploration play.Based on microfacies of cores,also using the log information and seismic data,the main types of sedimentary facies of Jurassic in Hongche area have been indentified.They include alluvial fan,braid river,braid delta,lake,etc.Above all,the sandstone on the braided-river delta front and mudstone in shore-shallow lake are alternatively deposited on the oscillation background during the period of late Badaowan Formation and Sangonghe Formation which possesses the good source reservoir cap assemblages,hence they are the favorable facies zones for lithologic trap.Then the main seismic facies of Jurassic in Hongche area is studied;and on the basis of the analysis on middle basal level cycle,the planar distribution characters of sand groups are identified and the evolution history of Jurassic sedimentation in Hongche area is reconstructed.At last,the relationship between the sedimentary facies and lithologic trap is discussed and the favorable area for the Badaowan Formation and Sangonghe Formation sedimentary is pointed out.