成岩相分析方法在南海北部深水区储层预测的应用——以珠江口盆地白云凹陷为例  

Application of Diagenetic Facies Analysis to Reservoir Prediction in Deep Water Area of the Northern South China Sea: A case study from Baiyun Sag,Zhujiangkou Basin

作　　者：梁建设[1] 王琪[2,3] 郝乐伟[2,3] 唐俊[2,3] 廖朋[2,3] 

机构地区：[1]中国海洋石油总公司研究总院,北京100027 [2]中国科学院油气资源研究重点实验室,兰州730000 [3]中国科学院研究生院,北京100049

出　　处：《沉积学报》2011年第3期503-511,共9页Acta Sedimentologica Sinica

基　　金：国土资源部全国油气资源战略调查与评价项目(编号:XQ-2004-05);中国科学院"西部之光"联合学者项目资助

摘　　要：成岩相分析方法旨在在碎屑岩储层成岩作用和孔隙演化之间建立一种成因联系,建立研究区孔隙演化与成岩作用关系模型,为孔隙演化机理和主控因素分析及储层平面分布预测提供理论依据。研究表明,机械压实、胶结和溶蚀作用是本区主控成岩作用类型,据此可划分出5种主要的成岩相组合:早期碳酸盐胶结弱溶蚀相、弱压实强溶蚀相(<1800m)、中等压实强溶蚀相(1800～2800m)、较强压实—较强溶蚀相(2800～3800m)和强压实—弱溶蚀相(﹥3800m)。其中深水区储层主要受控于较强压实较强溶蚀相,孔隙度分布在10%～20%之间,为Ⅲ类储层夹Ⅱ和Ⅰ类储层。珠海组(E32zh)总体以较强压实强溶蚀相为主,在三角洲平原水道、滨岸砂形成以Ⅱ类储层为主的优质储层分布区,这与第一个次生孔隙发育带有关。同样,受强溶蚀作用影响,在三角洲平原区形成了Ⅲ类储层夹部分Ⅱ类和Ⅰ类储层的相对有利储层分布区,而在三角洲前缘由于水动力条件相对较弱,砂岩粒度细,加之相对较强的压实改造,多形成Ⅲ类储层分布区。Analysis of diagenetic facies method aims at establishing the genetic link between the clastic reservoir diagenesis and the porosity evolution. The model reflecting this genetic link could provide important basis for explanation on mechanism relevant to porosity evolution and its main controls as well as vertical and horizontal distribution of favorable reservoir zone. The result of this research shows that mechanical compaction, cementation and dissolution are principal diageneses, and according to their associations, five diagenetic facies associations could be recognized as ： ①Early carbonate cement dissolution facies;②Weak compaction-strong dissolution facies（ 〈 1 800 m） ;③ Intermediate compaction-strong dissolution facies（ 1 800 -2 800 m）④Slightly strong compactionslightly strong dissolution facies（2 800 -3 800 m） and ⑤ Strong compaction-weak dissolution facies（ 〉 3 800 m）. The reservoir distributed in deep water area are controlled by slightly strong compaction- slightly strong dissolution facies with measured porosity ranging from 10% - 20%. Type m reservoir constitutes the major reservoir zone with some Type Ⅱ and I interlayer. Generally, Zhuhai Formation （E3^2zh）is dominated by slightly strong compactionslightly strong dissolution facies, and the high quality reservoirs are mainly composed of delta plain channel and beach sandstones due to porosity enhancement caused by the first secondary porosity zone. For the same reason, type m with minor type II and I reservoirs form the relatively favorable zone in the delta plain facies. Due to weak hydraulic dynamics and finer grain overlapped by strong compaction, type m reservoir prevails in the delta front area.

关 键 词：成岩相 深水区 储层预测 白云凹陷 南海北部 

分 类 号：P588.2[天文地球—岩石学]