准噶尔盆地北缘春晖油田侏罗系八道湾组湿地扇沉积及成藏效应*

春晖油田位于准噶尔盆地西北缘哈山（即“哈拉阿拉特山”）地区，主要含油层系为侏罗系八道湾组，对沉积相及有利储集层分布规律的研究制约着春晖油田的勘探工作。为此，根据野外露头、钻井、测井、取心及分析测试资料等，对春晖油田八道湾组开展了沉积相和有利砂体分布分析。研究结果表明，研究区八道湾组一段一砂组沉积时期，气候温暖潮湿，来自西北方向的多个物源形成的湿地扇沉积在研究区相互叠置，可识别出为扇根、扇中、扇缘3种亚相和6种岩石相（扇根砾岩相，扇中辫状河道砂砾岩相、辫状河道粗砂岩相、辫状河道细砂岩相，扇缘泥岩相和碳质泥岩及煤层相）；扇中粗砂岩相、细砂岩相为油气聚集的优势岩相带，亦是油气运移的优势通道，它决定了油气富集规模及油藏边界。

Sedimentology and accumulation effect of humid fan of the Jurassic Badaowan Formation in Chunhui Oilfield,northern margin of Junggar Basin

Chunhui Oilfield was located in Hashan area in the northern margin of Junggar Basin，of which the Jurassic Badaowan Formation is the main oil-bearing strata，and the sedimentary facies and favorable reservoir distribution regularity constrained the exploration of Chunhui Oilfield.Therefore，based on the data of outcrops，drilling，well logging，coring and laboratory analysis，this article carried out the analysis of sedimentary facies and the favorable reservoir distribution of the Badaowan Formation in Chunhui Oilfield.The results show that，it was warm and humid during the depositional period of the interval 1 of Member 1 of Badaowan Formation, and the humid fan sedimentary was formed by clastic materials from source areas located at northwest of the basin. The upper fan deposits，middle fan deposits and lower fan deposits were recognized in this area，and they were further divided into 6 lithofacies，including the upper fan conglomerate facies; the middle fan braided river glutenite facies，coarse sandstone facies，fine sandstone facies; the lower fan mudstone facies，carbonaceous mudstone and coal facies. The middle fan coarse conglomerate and fine sandstone facies are the most favorable accumulation lithofacies zones，as well as the dominant hydrocarbon migration pathway，which constrained the scale and boundary of hydrocarbon accumulation.