断陷湖盆早期浅水三角洲沉积——以高邮凹陷永安地区戴一段为例

发布时间：2019-04-26 05:31

【摘要】：浅水三角洲作为沉积学和油气勘探领域的热点,目前研究主要集中在大型拗陷型盆地内,对断陷湖盆关注较少。通过充分调研区域地质背景并结合永安地区戴一段的岩心、录井、测井、地震、分析化验等资料进行系统研究后认为,戴一段处于断陷早期,地形较为平缓,水体宽浅且波动频繁,气候温暖湿润,物源供给充足,具备形成浅水三角洲的有利沉积条件。研究区浅水三角洲为近源沉积,以牵引流为主;砂岩中多见强水动力沉积构造;垂向上发育进积、加积的沉积序列,具平行、亚平行及叠瓦状地震反射特征;以前缘亚相为主体,相带宽阔,可分为内、外前缘沉积,水下分流河道构成主要骨架砂体;在向湖推进过程中受沉积物可容纳空间与沉积物补给量比值(A/S)变化的影响较大,不同成因砂体类型及沉积样式呈现有规律的分布。基于以上分析,最终建立了断陷湖盆早期浅水三角洲的沉积模式,在一定程度上对丰富浅水三角洲的沉积学认识并拓展永安地区乃至整个高邮凹陷斜坡带油气勘探的领域和范围具有一定指导意义。
[Abstract]:As a hot spot in sedimentology and oil and gas exploration, shallow water deltas are mainly focused on large depression basins, but less attention is paid to faulted lacustrine basins. By fully investigating the regional geological background and combining with the core, logging, earthquake, analysis and laboratory data of the first section of Yongan area, it is considered that Dai member is in the early stage of fault depression, and the topography is relatively smooth. The water body is shallow and fluctuating frequently, the climate is warm and humid, the supply of provenance is sufficient, and it has the favorable sedimentary condition to form shallow water delta. The shallow water deltas in the study area are near-source sediments dominated by traction drainage strong hydrodynamic sedimentary structures in sandstone vertical progressive and accreted sedimentary sequences with parallel sub-parallel and imbricate seismic reflection characteristics. The front subfacies is the main body, the facies belt is wide, can be divided into inner and outer front deposition, underwater distributary channel constitutes the main skeleton sand body; The variation of sediment accommodation space to sediment recharge ratio (A S) is more important in the process of advancing towards the lake, and the distribution of different types of sand bodies and sedimentary patterns is regular. Based on the above analysis, the sedimentary model of the shallow water delta in the early fault basin has been established. To a certain extent, it is of great significance to enrich the sedimentology of shallow water delta and expand the field and scope of oil and gas exploration in Yongan area and even in the slope belt of Gaoyou Sag.
【作者单位】：中国石油大学(华东)地球科学与技术学院;中国石化胜利油田勘探开发研究院;中海石油(中国)有限公司上海分公司;中海油田服务股份有限公司;中国石化江苏油田分公司试采一厂;
【基金】：国家科技重大专项(2011ZX05009-003)~~
【分类号】：P618.13

【相似文献】