砂岩储集层凝灰质溶蚀作用的差异性及其物性响应——以珠一坳陷惠州—陆丰地区古近系文昌组为例  

Differences of tuffaceous components dissolution and their impact on physical properties in sandstone reservoirs:A case study on Paleogene Wenchang Formation in HuizhouLufeng area,Zhu I Depression,Pearl River Mouth Basin,China

作　　者：靳子濠 远光辉[1,2] 张向涛 操应长 丁琳[3] 李晓艳 傅筱涵 JIN Zihao;YUAN Guanghui;ZHANG Xiangtao;CAO Yingchang;DING Lin;LI Xiaoyan;FU Xiaohan(Key Laboratory of Deep Oil and Gas,China University of Petroleum,Qingdao 266580,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266071,China;China National Offshore Oil Corporation Limited-Shenzhen,Shenzhen 518067,China)

机构地区：[1]中国石油大学(华东)深层油气重点实验室,山东青岛266580 [2]海洋国家实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266071 [3]中海石油(中国)有限公司深圳分公司,广东深圳518067

出　　处：《石油勘探与开发》2023年第1期100-112,共13页Petroleum Exploration and Development

基　　金：国家自然科学基金项目(41872140);泰山学者青年专家项目(201909061);青岛海洋科学与技术试点国家实验室山东省专项(2021QNLM020001);中央高校创新基金(20CX06067A)。

摘　　要：以储集层显微分析为基础,通过主微量元素定量分析,对珠江口盆地珠一坳陷惠州—陆丰地区典型洼陷带古近系文昌组砂岩中凝灰质的元素地球化学特征及其成岩蚀变产物组合进行分析,并结合储集层物性特征,探讨不同凝灰质溶蚀作用对储集层物性的影响。结果表明,研究区发育酸性、中性、基性和碱性4类凝灰质杂基;酸性凝灰质经历强蚀变、蚀变产物难溶蚀的演化过程,蚀变沉淀大量高岭石,不能有效增孔升渗;中性和碱性凝灰质则表现出凝灰质强溶蚀、残余凝灰质强蚀变的演化过程,凝灰质溶蚀粒间孔发育,但自生石英、磷灰石和伊利石等蚀变产物使孔隙结构变差,凝灰质溶蚀作用最终导致储集层增孔不升渗;基性凝灰质以凝灰质溶蚀-蚀变产物强溶蚀的演化过程为主,粒间凝灰质与蚀变成因的浊沸石均可溶蚀成孔,凝灰质溶蚀作用能够显著改善储集层物性。The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical low-lying zones of the Huizhou-Lufeng area of the Zhu Ⅰ Depression, Pearl River Mouth Basin, were identified through microscopic analysis and quantitative analysis of main and trace elements. The impacts of dissolution of different tuffaceous components on physical properties of reservoirs were discussed through quantitative characterization of reservoir physical properties. The results show that there are mainly four types of tuffaceous components in the study area, which are acidic,intermediate, basic and alkaline tuffaceous components. The acidic tuffaceous components evolved in a process of strong alteration and weak dissolution of alteration products, with a large amount of kaolinite precipitated during alteration to disenable the improvement of porosity and permeability. The intermediate and alkaline tuffaceous components evolved in a process of strong dissolution of tuffaceous components and strong alteration of residual tuffaceous components;the dissolution of tuffaceous components created intergranular pores,but the alteration products such as autogenic quartz, apatite and illite deteriorated the pore structure;ultimately, the dissolution of tuffaceous components resulted in the increase of porosity but no increase of permeability of the reservoir. The basic tuffaceous components dominantly evolved in a process of dissolution of tuffaceous components to strong dissolution of alteration products;both tuffaceous components between particles and laumontite generated from alteration can be strongly dissolved to create pores;thus, the dissolution of tuffaceous components can significantly increase the physical properties of the reservoir.

关 键 词：珠江口盆地 珠一坳陷 惠州凹陷 陆丰凹陷 凝灰质 溶蚀作用 物性响应 古近系文昌组 

分 类 号：TE122.2[石油与天然气工程—油气勘探]