莺歌海盆地东方A气田莺歌海组二段沉积新认识:海底扇浊积席状砂

莺歌海盆地东方A气田莺歌海组的沉积模式存在争议。综合利用岩心、录井、测井等资料分析沉积相类型,在此基础上结合地震多属性及单井、连井分析,研究各气组的沉积演化,并对东方A气田沉积相形成的控制因素进行了总结。莺歌海组二段沉积时期发育三种沉积微相,分别为浊积席状砂、滨外滩坝及滨外泥。该段Ⅲ、Ⅱ气组主要发育来自西部物源的海底扇外扇浊积席状砂,Ⅰ气组主要为滨外滩坝沉积,滨外泥在各气组均有发育。东方A气田的沉积相受控于盆地的二级坡折带及沉积时期底辟的发生。本次研究关于莺歌海组二段浊积席状砂的认识,改变了以往强调东部海南岛物源的滨外滩坝的模式,为后期的开发调整起到了积极有效的作用。

Turbidite Sand:A New View on Sedimentary Facies of Pliocene Zhujiang Member-2 in DF-A Gas Field,Yinggehai Basin

The depositional model of the Pliocene Yinggehai Formation in DF-A gas field of Yinggehai Basin is controversial. Based on the comprehensive analysis of well core, logging data, and seismic multi-attributes, three sedimentary microfacies developed during Yinggehai Member-2 are turbidite sand, foreshore dam, and offshore mud. Controlled by the slope break of the basin and the occurrence of diapir during the depositional period, there developed sheet-like turbidite sand mainly in Ⅲ and Ⅱ gas group which derived from the western sea fan, and developed foreshore dam deposition mainly inⅠ gas group, and developed offshore mud widely in each gas group. This recognition of turbidite sand in Yinggehai Member-2, which changed the pattern of the foreshore dam derived from the eastern Hainan Island, have played an effective role in the later development and adjustment.