摘要
基于岩心观察、地震及钻、测、录井资料综合分析,以高分辨率层序地层学和沉积学理论为指导,重构波阻抗反演技术为手段,对民丰地区沙三段中亚段湖底扇砂岩体进行精细刻画与研究。结果表明,研究区沙三段中亚段深水湖底扇沉积主要受北东向永安镇三角洲物源体系影响,区域内发育滑动-滑塌砂岩体、砂质碎屑流砂岩体、底流改造砂岩体及浊流砂岩体等4种砂岩体沉积类型,并识别出7种典型岩相特征。平面上湖底扇呈现出以内扇滑动-滑塌高密度流、中扇砂质碎屑流以及外扇浊流为主的沉积演化过程,并在不同相对地层古坡度上差异分布。不同岩相及其组合类型受控于多期基准面旋回变化,且多发育于短期—超短期旋回顶、底界面。在基准面下降半旋回(A/S减小)阶段,碎屑流舌状体和浊流朵叶体较为发育且呈多期相互切割叠置;在基准面上升半旋回(A/S增大)阶段,碎屑流舌状体和浊流朵叶体多以孤立式或串珠状发育,并易受底流改造作用,形成小尺度的脉状或波状层理,部分可被切割而发生再次沉积。
Through comprehensive analysis of core observation and drilling,logging,and seismic data,and guided by highresolution sequence stratigraphy and theories of sedimentology,the sublacustrine fan sand bodies in the Middle Es_(3) in Min⁃feng area were finely characterized and studied by reconstructed wave impedance inversion.The results show that the deepwater sublacustrine fan deposits in Middle Es3 is mainly affected by the NE provenance system in Yong’an Town delta.Four sedimentary types of sand bodies are developed,i.e.,sliding-slump current,sandy debris current,turbidity current,and bottom current reworked sand bodies,and seven types of lithofacies are identified in the study area.On the plane,the sedimentary evolution of the sublacustrine fan are dominated by high-density sliding-slump current in the inner fan,sandy debris current in the middle fan,and turbidity current in the outer fan,which are differentially distributed on the strata with different relative paleoslopes.Further analysis shows that different lithofacies and their assemblages of the sand bodies are controlled by the multi-period base-level cycles,and most of them are developed at the top-bottom interfaces of short-and ultra-short-term cycles. Debris current tongues and turbidite lobes are developed well and they are mutually cut and super⁃posed when the base level is in the descending semi-cycle(A/S falls). On the contrary,they often are developed in isolationor in beads when the base level is in the ascending semi-cycle(A/S rises);moreover,they are easily reformed by bottomcurrent,forming small-scale vein-like or wave-like bedding,part of which can be cut and redeposited.
作者
宋明水
茆书巍
林会喜
郝雪峰
巩建强
张鹏飞
邱贻博
王园园
SONG Mingshui;MAO Shuwei;LIN Huixi;HAO Xuefeng;GONG Jianqiang;ZHANG Pengfei;QIU Yibo;WANG Yuanyuan(SINOPEC Geophysical Corporation,Beijing City,100020,China;Exploration and Development Research Institute,Shengli Oilfield Company,SINOPEC,Dongying City,Shandong Province,257015,China;Petroleum Exploration and Development Research Institute,SINOPEC,Beijing City,100083,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2021年第3期1-13,共13页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项“近岸深水粗碎屑岩沉积构型与有利储层评价”(2017ZX05009-002)。
关键词
湖底扇
岩相
滑塌变形构造
古坡度
民丰地区
东营凹陷
sublacustrine fan
lithofacies
slump deformation structure
paleoslope
Minfeng area
Dongying Sag
