【摘要】 运用地震、岩心、钻测井和古生物等资料,对苏北盆地白驹凹陷泰州组进行了层序地层和沉积相分析,在泰州组地层中可识别出3个层序界面,划分出2个三级层序(SQ1、SQ2)和4个体系域。根据沉积相标志,在泰州组沉积体中识别出了辫状河三角洲、(曲流河)三角洲及湖泊3种沉积相类型,并进一步划分为8种亚相和17种微相。其中,SQ1沉积于盆地初始断陷期,以发育辫状河三角洲为特征;SQ2低位体系域沉积时期,盆地的拉张作用增加,湖盆范围扩大,(曲流河)三角洲沉积最为发育;SQ2湖侵体系域和高位体系域沉积时期,盆地发育由断陷湖盆转为坳陷湖盆,湖侵体系域湖泊沉积范围最广,主要为半深湖—深湖亚相沉积环境,高位体系域湖平面略有下降,以滨浅湖沉积环境为主。指出白驹凹陷生油层主要发育于SQ2湖侵体系域,其本身又是良好的盖层;而储集层则主要发育在SQ1-SQ2低位体系域以及SQ2高位体系域,之间相互组合形成了2套生储盖组合,生储盖的良好配置使白驹凹陷发育的辫状河三角洲前缘水下分流河道、三角洲前缘水下分流河道、席状砂以及滨浅湖砂滩、砂坝砂体成为有利的油气勘探区。更多还原

【Abstract】 Using seismic data,drilling core,well logs and paleontology data,the authors studied the sequence stratigraphy and sedimentary facies of Taizhou Formation in Baiju sag of Subei basin,identified three sequence boundaries in Taizhou Formation and divided Taizhou Formation into 2 third-order sequences(SQ1,SQ2) and 4 system tracts.According to sedimentary signatures,the authors recognized three facies types in Taizhou Formation,i.e.,braided-river delta,meandering-river delta and lacustrine facies,which can be subdivided into 8 types of sedimentary subfacies and 17 types of sedimentary microfacies.SQ1 was deposited during the initial faulting period of the basin,characterized by the development of braided-river delta.In the period of the lowstand system tracts of SQ2,the extension of basin was increased,and the area of lake was enlarged,and meandering-river delta was developed.In the period of the transgressive system tracts and high-stand system tracts of SQ2,the development of basin transformed the faulting period into the shrinking period,the area of lake was the biggest and semi-deep and deep lake subfacies were developed in the period of the transgressive system tracts of SQ2,the water-level was declined slightly and shallow-shore lake facies was developed in the period of the high-stand system tracts of SQ2.The main source rocks were developed in the transgressive system tracts of SQ2 which also served as good capping formation.The sand body reservoirs composed of underwater distributary channels of braided-river delta front,underwater distributary channels and sheet sand of meandering-river delta front were developed in the low-stand system tracts of SQ1-SQ2,sandy beach and sandy bar of shallow-shore lake in the high-stand system tracts of SQ2,which constitute the potential areas for oil and gas.更多还原