渤海莱州湾凹陷古近系沙一二段沉积体系

Depositional System of the Sha1,2 Formation (Paleogene) in Laizhouwan Sag,Bohai Bay

在分析了大量岩心、录井、测井及地震资料基础上,运用含油气盆地沉积学的理论和方法,查明了渤海莱州湾凹陷古近系沙一二段沉积体系的类型、特征及分布规律。莱州湾凹陷古近系沙一二段为东断西超的断陷湖盆,发育辫状河三角洲、扇三角洲及湖泊沉积体系,辫状河三角洲占优势。辫状河三角洲体系发育于莱州湾凹陷西部。扇三角洲仅靠近莱州湾凹陷东部盆缘断裂和南部盆缘陡坡发育,且规模较小。辫状河三角洲和扇三角洲分布区发育优质油气储层,是油气勘探的重点区带。

The utilization the oil and gas bearing basin sedimentology's theory and the method,based on the massive core,the logging,the well logging and the seismic data analysis,the deposition system's type,the characteristic and the distributed rule of the Sha1,2 Formation(Paleogene) in Laizhouwan Sag,Bohai Bay has been verified.Laizhouwan Sag is one of the typical rift lacustrine basins(断陷湖盆) in the Bohai Gulf Basin,the fault boundary on the east,and onlap in the west,the braided river delta,fan delta and the lacustrine deposit system developed in the sag,but the braided river delta is predominate.The braided river delta system developed in the western,fan delta only developed in the eastern part nearby the basin margin rift and in the southern part nearby the basin margin actic region,and the scale is small.The braided river delta and the fan delta distribution area,developed high quality reservoir of oil gas,is the oil-gas exploration key area belt.