鄂尔多斯盆地东部太2上段储层特征及有利区预测  

Reservoir Characteristics and Favorable Zone Prediction of the Upper Tai-2 Section in the Eastern Ordos Basin

作　　者：孙亚辉 杨申谷[1] 陈小虎 马银银 SUN Ya-hui;YANG Shen-gu;CHEN Xiao-hu;MA Yin-yin(College of Geosciences,Yangtze University,Wuhan 430100,China;No.1 Gas Production Plant of Jianghan Oilfield Branch,Chongqing 404100,China)

机构地区：[1]长江大学地球科学学院,武汉430100 [2]江汉油田分公司采气一厂,重庆404100

出　　处：《科学技术与工程》2025年第3期900-911,共12页Science Technology and Engineering

基　　金：国家科技重大专项(201X05007-004)。

摘　　要：为查明鄂尔多斯盆地东部太原组储层发育影响因素,利用铸体薄片、高压压汞、恒速压汞等实验方法开展了太2上段储层孔隙结构特征的研究。结果表明,太2上段储层平均孔隙度为7.84%、平均渗透率为0.396 mD,以特低孔-超低渗为主,孔隙结构复杂,非均质性强。储层发育粒内溶孔、粒间溶孔、晶间孔、岩屑溶孔等;根据各区域孔隙发育频率、孔隙度与渗透率,将孔隙组合分为3类:粒内溶孔、粒内溶孔+晶间孔、粒内溶孔+粒间溶孔,高压压汞和恒速压汞的实验方法能够较好地表征3类孔隙组合的储层特征,其中粒内溶孔+晶间孔的组合是良好的储层孔隙类型。根据沉积分异和孔隙分异规律,在实验结果的基础上建立优质储层评价标准,将太2上段储层由好到差分为Ⅰ、Ⅱ、Ⅲ类,并对优质储层有利区做出预测。The influencing factors on the reservoir development of Upper Taiyuan Formation in the eastern Ordos Basin were investi-gated.Experimental methods such as casting thin sections,high-pressure mercury intrusion,and constant-rate mercury intrusion were employed to examine the pore structure characteristics of Upper Taiyuan Formation,Tai 2 Member.Results show that the average po-rosity of Tai 2 Member reservoir is 7.84%,with an average permeability of 0.396 mD,primarily characterized by ultra-low porosity and permeability.The pore structure is complex,with strong heterogeneity.Various types of pores were developed in the reservoir,in-cluding intragranular dissolution pores,intergranular dissolution pores,intercrystalline pores,and rock fragment dissolution pores.Based on the frequency of pore development,porosity,and permeability in each region,the pore combinations are classified into three types:intragranular dissolution pores,intragranular dissolution pores combined with intercrystalline pores,and intragranular dissolution pores combined with intergranular dissolution pores.The experimental methods of high-pressure mercury intrusion and constant-rate mercury intrusion could effectively characterize the reservoir characteristics of these three types of pore combinations,among which the combination of intragranular dissolution pores and intercrystalline pores represents a favorable reservoir pore type.Based on the laws of sedimentary differentiation and pore differentiation,a set of criteria for evaluating high-quality reservoirs is established on the basis of experimental results.Upper Taiyuan Formation reservoir was classified into ClassⅠ,Ⅱ,andⅢfrom good to poor,and predictions were made for favorable areas of high-quality reservoirs.

关 键 词：鄂尔多斯盆地 太2上段 储层特征 孔隙结构 

分 类 号：P618.13[天文地球—矿床学]