准噶尔盆地小拐油田佳木河组中段沉积相辨析

Analysis of Sedimentary Facies of Middle Member of Permian Jiamuhe Formation in Xiaoguai Oilfield of Junggar Basin

准噶尔盆地西北缘小拐油田二叠系佳木河组中段沉积相一直被认为是冲积扇相或扇三角洲相。然而根据沉积特征、构造环境和地震反演结果分析,认为这套粗碎屑混杂堆积,结构构造成熟度非常低,毫无水动力搬运痕迹,不具备冲积扇的一些基本特征,同时发育大量火山熔岩、火山凝灰岩,对此应合理解释为火山喷发相沉积。

The sedimentary facies of the middle member of Permian Jiamuhe formation in Xiaoguai oilfield in northwestern margin of Junggar basin was always considered as alluvial fan or fan delta facies deposit.However,from point of view of petrology,it is definitely different from the standard alluvial fan facies.As early as 1996 it was considered as volcanic eruptive facies,but at that time,＂fan control＂ theory was prevalent,this understanding was not paid more attention to.On the fifteenth anniversary of the reservoir exploration,this paper presents the understandings about it,so as to deepen the recognition of petroleum geology in this area.