摘要
东海盆地西湖凹陷孔雀亭地区勘探程度高,油气资源丰富。根据薄片、扫描电镜及X射线衍射等资料,分析了孔雀亭地区平湖组成岩作用及其对孔隙演化的影响。研究结果表明:(1)东海盆地孔雀亭地区平湖组主要为三角洲-海湾沉积环境,平下段下部和上部主要为潮坪沉积环境,平中段和平上段由潮坪沉积环境过渡为三角洲沉积环境。(2)孔雀亭地区平湖组储层岩石类型主要为长石岩屑砂岩,储层砂岩成分成熟度中等,结构成熟度高,为低孔低渗储层,平均孔隙度为10.44%,平均渗透率为25.65 mD。(3)研究区经历了多种成岩作用,压实作用降低了储层物性,胶结作用使储层物性变差,但在一定程度上也使得岩石具有抗压实作用,保护了原生粒间孔,溶蚀作用对储层物性具有一定的改善作用。(4)研究区储层主要处于晚成岩A2期,在3 000~3 500 m和4 000~4 400 m处形成了2个次生孔隙发育带,相对优质的储集性有利于油气的聚集成藏。
Kongqueting area in Xihu Sag of the East China Sea Basin is highly explored and rich in oil and gas.Through the data of cast thin section,scanning electron microscope and X-diffraction,the diagenesis of Pinghu Formation and its influence on pore evolution in Kongqueting area of Xihu Sag were analyzed.The results show that:(1)The Pinghu Formation in Kongqueting area of the East China Sea Basin is mainly delta-bay sedimentary environment.The lower and upper parts of the lower member of Pinghu Formation are mainly tidal flat sedimentary environment,and the middle and upper members of Pinghu Formation transit from tidal flat to delta sedimentary environment.(2)The reservoir rocks of Pinghu Formation in Kongqueting area are mainly feldspathic lithic sandstone,with medium composition maturity and high structural maturity.It is a low porosity and low permeability reservoir,with an average porosity of 10.44% and an average permeability of 25.65 mD.(3)The study area has experienced a variety of diagenesis.Compaction reduces reservoir physical properties,cementation makes the reservoir physical properties poor,but to a certain extent,the cements can resist compaction and protect the primary intergranular pores,and dissolution is an important factor to improve reservoir physical properties.(4)The reservoir in the study area is mainly in the late diagenetic A2 stage.Two secondary pore development zones were formed at 3 000-3 500 m and 4 000-4 400 m.The relatively high quality reservoirs are conducive to hydrocarbon accumulation.
作者
李盛谦
曾溅辉
刘亚洲
李淼
焦盼盼
LI Shengqian;ZENG Jianhui;LIU Yazhou;LI Miao;JIAO Panpan(PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China;State Key Laboratory of Oil and Gas Resources and Exploration,China University of Petroleum(Beijing),Beijing 102249,China;PetroChina Changqing Oilfield Company,Xi’an 710200,China)
出处
《岩性油气藏》
CAS
CSCD
北大核心
2023年第5期49-61,共13页
Lithologic Reservoirs
基金
国家自然科学基金面上项目“基于润湿性影响下的深层低渗透砂岩油气成藏机理研究”(编号:41972147)资助。
