气孔杏仁状玄武岩有利储层划分方案初探——以新疆乌尔禾地区哈拉阿拉特组第一岩性段为例  

Preliminary Exploration of Reservoir Division Scheme for Vesiculate Amygdaloidal Basalt——A Case Study of the First Lithologic Member of Hala'alate Formation in Urho Area of Xinjiang,China

作　　者：张景[1] 李永军[2] 覃建华[1] 李思远[1] 阿克丹·斯坎迪尔 王盼龙 王鑫[1] 黄家瑄 张新远 ZHANG Jing;LI Yong-jun;QIN Jian-hua;LI Si-yuan;AKEDAN·Sikandier;WANG Pan-long;WANG Xin;HUANG Jia-xuan;ZHANG Xin-yuan(Research Institute of Exploration and Development,Xinjiang Oilfield Company,PetroChina,Karamay 834000,Xinjiang,China;School of Earth Science and Resources,Chang'an University,Xi'an 710054,Shaanxi,China)

机构地区：[1]中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000 [2]长安大学地球科学与资源学院,陕西西安710054

出　　处：《地球科学与环境学报》2023年第5期1210-1226,共17页Journal of Earth Sciences and Environment

基　　金：国家科技重大专项项目(2017ZX05008-006-003-001);国家重点研发计划项目(2018YFC060400);中国石油天然气股份有限公司项目(2021DJ0405,2022DJ0507)。

摘　　要：气孔杏仁状玄武岩是准噶尔盆地西北缘乌尔禾地区新确立的主要储层之一,已发现的火山岩型油气藏至少有一半产于哈拉阿拉特组火山岩中。该组第一岩性段气孔杏仁状玄武岩极为发育,占该段总厚度的78%以上,是研究火山岩储层的理想层位。杏仁体成分几乎全为易被水溶解的次生方解石,多呈圆状—次圆状,多数连通呈网状、树枝状和不规则状。经统计确认,井中水介质溶解杏仁体后,其孔隙度增加3.6~4.5倍,因而成为理想的储层岩类。设定气孔单位面积占比、连通性占比、杏仁体水解增孔占比这3个单项评价指标在同一件样品中均达优级时为优级储层,至少2项指标达优级时为良级储层。因此,保守估计110件样品中超过50%的样品可达良级及以上,总体显示出良好储集潜力。上述划分方案可以为建立气孔杏仁状玄武岩的储集性能综合评价方案提供参考。Vesiculate amygdaloidal basalt stands out as a recently recognized primary reservoir within Urho area,the northwestern periphery of Junggar Basin.Notably,a significant proportion of the volcanic rock-type oil and gas reservoirs discovered in this region is affiliated with the volcanic formations of Hala'alate Formation.Within this stratigraphic unit,a distinct segment characterized by vesiculate amygdaloidal basalt exhibits remarkable development,encompassing over 78% of the total thickness of the strata.This particular interval serves as an optimal candidate for in-depth studies on volcanic rock reservoir characteristics.The amygdaloid bodies in these basalts predominantly consist of secondary calcite,which demonstrates a high solubility in water.These amygdaloid bodies often assume circular to semi-circular configurations,with many interconnected in patterns resembling networks,branches,or irregular structures.Statistical analyses corroborate that subjecting these amygdaloid bodies to dissolution in wellbore fluids results in a significant increase in porosity,approximately ranging from 3.6 to 4.5 times,effectively rendering them highly favorable as reservoir lithology.A robust assessment of the reservoir quality considers three distinct parameters,including stomatal unit area proportion,the proportion of connectivity,and the proportion of porosity enhancement stemming from amygdaloid dissolution.When all three of these criteria achieve excellence,the reservoir attains a classification of excellent reservoir.Meanwhile,a classification of favorable reservoir is attributed when a minimum of two criteria reaches an excellent level.A prudent estimation indicates that over 50% of the 110 samples obtained from a dataset surpass the established criteria for a favorable reservoir,thus demonstrating a noteworthy potential for reservoir development.The above reservoir division scheme provides a reference for establishing comprehensive evaluation scheme of evaluating the reservoir performance specific to vesiculate amygda

关 键 词：气孔杏仁状玄武岩 气孔单位面积占比 气孔连通性 杏仁体连通性 杏仁体水解增孔占比 储集性能评价 哈拉阿拉特组 准噶尔盆地 

分 类 号：P583[天文地球—岩石学] P618.13[天文地球—地质学]