南海北部湾盆地迈陈凹陷中南部古近系储层特征与控制因素——以区域探井Y井为例  

CHARACTERISTICS OF EOCENE RESERVOIRS IN THE SOUTH CENTRAL MAICHEN SAG,BEIBUWAN BASIN AND CONTROLLING FACTORS:A CASE FROM THE OUTPOST WELL Y

作　　者：于书友 何家雄 张伟[3,4] 刘菊[5] 李晓唐 刘志杰 张景茹 龚晓峰 YU Shuyou HE Jiaxiong ZHANG Wet LIU Ju LI Xiaotang LIU Zhijie ZHANG Jingru GONG Xiaofeng(Zhanjiang Branch, CNOOC Energy Technology and Service-Drilling and Production Company Zhanjiang 524057, Guangdong, China University of Chinese Academy of Sciences, Beijing 100049, China Guangzhou Marine Geological Survey, CGS, Guangzhou 510075, China Sun Yat-sen University, Guangzhou 510275, China South Oil Exploration and development Company, Guangzhou 510240, China)

机构地区：[1]中海油能源发展工程技术湛江分公司,广东湛江524057 [2]中国科学院大学,北京100049 [3]中国地质调查局广州海洋地质调查局,广州510075 [4]中山大学,广州510275 [5]南方石油勘探开发有限责任公司,广州510290

出　　处：《海洋地质前沿》2017年第10期9-21,共13页Marine Geology Frontiers

基　　金：中石油南方石油勘探有限责任公司科技攻关项目(2011-NFZY-003);国家自然科学基金(41176052)

摘　　要：北部湾盆地迈陈凹陷中南部Y井井壁取心分析、岩屑样品的薄片鉴定结果及地球物理测井综合评价表明,其钻遇的不同层位层段的储层类型主要以含泥质较高的砂岩、粉砂岩及泥质粉砂岩为主,少量砾岩,多属于近—中物源快速沉积充填、储集物性偏差的储集层类型,且成岩程度偏低(处在早成岩A或B期或中成岩A期),总体上属于岩性较细、泥质含量偏高、孔渗参数偏低的中孔中渗和低孔低渗及低孔特低渗型砂岩储层类型。其中,钻遇的渐新统涠洲组砂岩储层总体上偏细且泥质含量较高,砂岩有效孔隙度和渗透率偏低,属于储集物性较差储层;始新统流沙港组二段砂岩属于差—较好储层,储层孔隙类型以粒间孔为主,其次为粒间溶孔,还发育有少量或微量长石溶孔和粒内溶孔,具有一定的孔渗性;古新统长流组砂岩孔隙类型以粒间孔、粒间溶孔为主,发育少量长石溶孔及粒内溶孔,储层致密储集物性偏差。总之,本区储层发育主要受控于碎屑物物源供给远近与沉积相及成岩作用,但总体上储层成岩程度较低,加之溶蚀作用及胶结作用普遍,故严重影响了储层储集物性。The results of section identification, geophysical and well logging data from side-wall coring and debris of the borehole Y, that is located in the southwest Maichen sag of the Beibuwan Basin, suggest that the sequence penetrated by the hole are dominated by sandstone intercalating great a- mount of shale, siltstone and pelitic siltstone, and small quantity of conglomerate deposited near the proximity and middle part of the provenance. The Oligocene reservoirs in the Weizhou Formation, which are fine and rich in mud in genaral, are characterized by poor physical properties and weak dia- genesis （A or B stage of eogenetic and A stage of middle diagenetic phase） As a whole, the effective porosity and permeability are low. However, the 2nd Member of the Liushagang Formation is a reser- voir with certain amount of porosity and permeability. It is dominated by intergranular pore with in- tergranular dissolved pores as the subordinate. Feldspar corrosion pores are observed sometimes. The pores in the Changliu Formation are largely composed of intergranular pores, intergranular dissolved pores and small amounts of feldspar corrosion pores. The development of reservoirs is mainly con- trolled by the distance to provenance, sedimentation environment, and diagenesis. Diagenesis in gen- eral is weak. Compaction, dissolution and cementation are the main diagenetic processes which affect the reservoir properties.

关 键 词：岩石学特征 储层物性 古近系砂岩储层 控制因素 迈陈凹陷中南部 

分 类 号：P618.18[天文地球—矿床学]