摘要
通过钻井、岩心、测录井及地震资料的综合分析,系统研究了四川盆地蓬莱—中江地区震旦系灯影组二段气藏的成藏特征。研究结果表明:(1)四川盆地灯影组沉积期,随着海水侵入,古陆多被淹没或侵蚀夷平,盆地逐渐演变为碳酸盐岩台地。灯二上亚段沉积期,川中北斜坡蓬莱—中江地区以发育台地边缘滩相和台地边缘丘相为特色,并可细分为滩核、滩缘、滩间海、丘核、丘缘、丘间海6种亚相,是储层发育的有利相带。(2)研究区灯二上亚段储层以藻云岩、藻砂屑云岩为主要储集岩,发育残余粒间孔+粒间溶孔型、粒内溶孔+藻格架孔型、裂缝型与孔洞型4种类型的储层,储层厚度分布特征与沉积相分布特征较吻合,位于台地边缘丘滩核的储层累积厚度大。(3)研究区灯二上亚段气藏的天然气主要来源于筇竹寺组烃源岩,烃源岩厚度大、有机碳含量及热演化程度高,气藏具备较好的烃源条件和封盖条件,具有“上生下储上盖”和“旁生侧储上盖”2种较好的生-储-盖配置关系。(4)研究区油气充注主要发生于三叠纪—白垩纪,为多期“准连续”型,灯二上亚段气藏主要经历了奥陶纪—志留纪古油气藏聚集阶段、志留纪—石炭纪古油藏破坏阶段、二叠纪—三叠纪再次生烃成油藏阶段和三叠纪—侏罗纪原油裂解生气阶段。
Based on the comprehensive analysis of drilling,logging,seismic and core data,the reservoir accu-mulation characteristics of the second member of Sinian Dengying Formation in Penglai-Zhongjiang area were systematically studied.The results show that:(1)During the sedimentary period of Sinian Dengying Formation in Sichuan Basin,with the intrusion of seawater,the ancient land was mostly submerged or eroded and flat-tened,and the basin gradually evolved into a carbonate platform.During the sedimentary period of the upper sub-member of the second member of Sinian Dengying Formation(upper Sinian Deng-2 member),platform margin shoal facies and platform margin mound facies were developed in Penglai-Zhongjiang area,and they can be fur-ther divided into six subfacies:shoal core,shoal edge,intershoal sea,mound core,mound edge,and inter-mound sea,which are favorable facies zones for reservoir development.(2)The reservoirs in the upper submem-ber of the second member of Dengying Formation in the study area are mainly composed of algal dolomite and algal sand clastic dolomite,with four types of reservoirs developed:residual intergranular pore and intergranular dis-solved pore type,intragranular dissolved pore and algal framework pore type,fracture type and pore type.The thickness distribution characteristics of the reservoirs are consistent with the sedimentary facies distribution char-acteristics,and the reservoirs located in the mound/shoal core of platform margin have a larger cumulative thick-ness.(3)The natural gas in the upper submember of the second member of Dengying Formaiton in the study area is mainly derived from the source rocks of Qiongzhusi Formation.The source rocks have a large thickness,high organic carbon content and high degree of thermal evolution.The gas reservoir has good hydrocarbon sources and sealing conditions,with two types of good assemblages:“upper source,lower reservoir and upper cap”and“side source,side reservoir,and upper cap”.(4)The oil and gas filling in the study area mainly occurred during Triassic-Cretaceous,which is multi-stage quasi-continuous.The gas reservoirs of the upper submember of the second member of Dengying Formation mainly mainly went through four stages:the accumulation stage of paleoreservoirs from Ordovician to Silurian,the paleo-reservoirs failure stage from Silurian to Carboniferous,the hydrocarbon regeneration and reaccumulation stage from Permian to Triassic,and the crude oil cracking and gas gener-ation stage from Triassic to Jurassic.
作者
岑永静
梁锋
王立恩
刘倩虞
张鑫哲
丁熊
CEN Yongjing;LIANG Feng;WANG Lien;LIU Qianyu;ZHANG Xinzhe;DING Xiong(North Central Sichuan Gas Production Management Office,PetroChina Southwest Oil and Gas Field Company,Suining 629000,Sichuan,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China)
出处
《岩性油气藏》
CAS
CSCD
北大核心
2024年第2期89-98,共10页
Lithologic Reservoirs
基金
中国石油西南油气田分公司科研项目“蓬莱地区灯二气藏成藏模式及气水分布研究”(编号:2021DZ-04)资助。
关键词
台地边缘相
藻云岩
藻砂屑云岩
旁生侧储
上生下储
原油裂解生气
筇竹寺组烃源岩
灯影组二段
震旦系
蓬莱—中江地区
四川盆地
platform margin facies
algal dolomite
algal sand-clastic dolomite
side source and side reservoir
upper source and lower reservoir
crude oil cracking and gas generation
source rocks of Qiongzhusi Formation
the second member of Dengying Formation
Sinian
Penglai-Zhongjiang area
Sichuan Basin
