埋藏条件对渤海海域沙垒田凸起周缘中生界储层的影响  

Influences of the burial conditions on Mesozoic reservoir in the margin of Shaleitian Uplift in Bohai Sea area

作　　者：卢欢 牛成民 王清斌 张友 任健 LU Huan;NIU Chengmin;WANG Qingbin;ZHANG You;REN Jian(CNOOC China Limited Tianjin Branch,Tianjin 300450,China)

机构地区：[1]中海石油(中国)有限公司天津分公司

出　　处：《大庆石油地质与开发》2019年第6期22-31,共10页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家科技重大专项“渤海海域勘探新领域及关键技术研究”(2016ZX05024-003)

摘　　要：通过岩心观察、薄片鉴定、扫描电镜、X衍射等多种分析手段,对渤海海域C12构造和Q17构造中生界碎屑岩储层进行了研究,以期为落实储层主控因素、进一步寻找中生界优质碎屑岩储层发育带打下基础。Q17构造储集空间类型主要以原生粒间孔为主,其次为粒间、粒内溶蚀孔;C12构造以裂缝为主,其次为粒内溶蚀孔,Q17构造储层物性优于C12构造。研究认为:埋藏条件对储层物性差异起到了决定性影响,并首次提出反复深埋藏的概念;Q17构造储层处于浅埋藏条件,其成岩阶段可划分为早成岩B期和中成岩A1期;C12构造储层处于反复深埋藏条件,其成岩阶段可划分为中成岩A期和早成岩B期;由于浅埋藏,Q17构造储层压实作用弱、热演化程度低、长石溶解作用强、高岭石大量发育,因此储层物性普遍较好;而由于反复深埋藏,C12构造储层压实作用强、热演化程度高,仅在中生界顶部发育高岭石高含量带,对应的储层物性较好,中深部储层大量伊利石化,造成渗透率严重恶化,致密储层发育。浅埋藏是中生界优质储层发育的决定性因素,而反复深埋藏对中生界储层起到了主要破坏性作用。With the help of the core observation, slice identification, X-ray diffraction and the other analyzing methods, Mesozoic clastic strata in Structure C12 and Q17 of Bohai Sea area were studied to lay the bases of determining the main controlling factors of the reservoirs and further finding out the developed belt of the Mesozoic high-quality clastic reservoirs. The accumulating spaces of Structure Q17 are mainly composed of the primary intergranular pores, the next is the intergranular and intragranular dissolution pores. Structure C12 is mainly composed of the fractures, the next is the intragranular dissolution pores, and the physical properties of the reservoirs in Structure Q17 are more favorable than those of Structure C12. The studies show that the burial conditions play the deterministic impact on the influence of the physical property variation of the reservoirs and moreover the concept of repeated deep burial was first proposed;the diagenetic stage of the reservoir in Structure Q17 under the condition of the shallow burial can be divided into Early B and Medium A1 diagenetic stages;while the stage in Structure C12 can be classified into Medium A and Early B diagenetic stages;the shallow burial in Structure Q17 results in week reservoir compaction, low thermal evolution degree, strong feldspar dissolution and well-developed kaolinite, so the physical properties of the reservoir are generally better;whereas due to the repeated deep burial, the reservoir in Structure C12 is characterized by strong compaction and high thermal evolution degree, only on Top Mesozoic, the high kaolinite-bearing belt is well-developed, the corresponding physical properties of the reservoir are pretty better, while in the middle part of the reservoir, large volume of the illite is generated, so the permeability is seriously deteriorated and the tight reservoirs are well-developed. The shallow burial is the deterministic factor of the development of Mesozoic high-property reservoir;on the contrary, the repeated deep burial plays th

关 键 词：物性特征 孔隙类型 埋藏条件 中生界 成岩作用 

分 类 号：TE122.2[石油与天然气工程—油气勘探]