准噶尔盆地白垩系岩相古地理

该文通过露头、钻井、测井、地震等资料,对准噶尔盆地白垩系岩相古地理特征进行了分析。盆地共发育冲积扇、辫状河、冲积平原、三角洲、滨浅湖及半深湖等沉积相。岩性上冲积扇以砂砾岩为主,辫状河以含砾砂岩、中细砂岩为主,三角洲以细砂岩、粉砂岩为主,冲积平原、滨浅湖及半深湖则以泥岩为主;底砾岩层主要发育冲积扇、辫状河及冲积平原沉积。清水河组、呼图壁河组、胜金口组—连木沁组各个沉积时期,均发育三角洲、滨浅湖及半深湖沉积。东沟组沉积时期,辫状河、泛滥平原发育。清水河组、呼图壁河组三角洲砂体为盆地白垩系的有利储层及勘探目标。

LITHOFACIES PALEOGEOGRAPHY OF THE CRETACEOUS IN THE JUNGGAR BASIN

Based on the outcrop, drilling, logging and seismic data, the lithofacies paleogeographical cha racteristics of the Cretaceous in the Junggar Basin were analysed. The basin developed alluvial fan, braided stream, alluvial plain, delta, shore shallow lake and semideep lake sedimentary facies. Lithologically, the alluvial fan was dominated by sand conglomerate, the braided stream by gravelly sandstone and moderate fine sandstone, the delta by microsandstone and siltstone, and the allluvial plain, the shore shallow lake and the semideep lake by mudstone. Alluvial fan, braided stream and alluvial plain deposits were developed in basal conglomerate layers. During the sedimentary periods of the Qingshuihe Group, the Hutubihe Group and the Shengjinkou Lianmuqin Group, delta, shore shallow lake and semideep lake deposits were developed, And braided stream and flood plain deposits were developed in the sedimentary period of the Donggou Group. The delta sandbodies of the Qingshuihe Group and the Hutubihe Group were the favorable reservoirs and exploration targets of the Gretaceous in the basin.