鄂尔多斯盆地黄陵探区浅埋藏致密油储层特征及“四元”分类评价新方法  

Characteristics and New"Four Parameters"Classification Evaluation Method of Shallow Buried Tight Oil Reservoir in Huangling Area of Ordos Basin

作　　者：王猛 吴小斌[2] 高其宇 钱昭良 WANG Meng;WU Xiaobin;GAO Qiyu;QIAN Zhaoliang(No.5 Gas Production Plant,Yanchang Gasfield,Yan’an,Shaanxi 716000,China;College of Petroleum&Environment Engineering,Yan’an University,Yan’an,Shaanxi 716000,China)

机构地区：[1]延长气田公司采气五厂,陕西延安716000 [2]延安大学石油与环境工程学院,陕西延安716000

出　　处：《西安石油大学学报(自然科学版)》2025年第2期11-22,64,共13页Journal of Xi’an Shiyou University(Natural Science Edition)

基　　金：国家自然科学基金地区科学基金项目“深水相致密砂岩CO_(2)溶蚀机理及其强化封存机制”(42062011);陕西省重点实验室基金项目“致密砂岩油藏体积压裂多尺度渗吸规律研究”(WSFRM20210502002);陕西省教育厅专项“致密砂岩储层微观孔喉结构连续定量表征及其对渗流规律的制约机制研究”(23JK0737)。

摘　　要：浊积砂体是鄂尔多斯盆地三叠系延长组黄陵探区内重要的油气储层类型,受沉积及成岩的影响,物性差属低渗致密砂体储层。为了进一步揭示研究区浅埋藏致密油储层特征,采集了14口钻井260件样品进行大量的测试分析,在铸体薄片、能谱、X-衍射、扫描电镜、高压压汞以及恒速压汞等实测资料的基础上,对储层的岩石学特征、微观孔喉特征进行分析,结合测井资料研究储层四性关系,建立了适合黄陵双龙-腰坪地区“四元”分类评价参数,以便进一步指导油气勘探的实践工作。研究表明:快速混源沉积、缺乏分选、岩屑偏多是致密储层的基础原因;溶蚀作用欠发育,后期碳酸盐胶结加剧了储层的致密化。埋深浅,驱动压力低以及平均主流喉道偏细,且发育多类型黏土矿物是储层渗流差的原因。整体储层物性与孔喉半径呈正相关,与排驱压力呈负相关,孔隙度受孔喉均值而渗透率受主流喉道半径控制明显。油层评价时选取“四元”(声波时差、电阻率、自然伽马及含油饱和度)标准化处理后,计算并选取得出其分类系数“Ψ”大于1.1作为优质油层的判别标准。Turbidite sandstone is an important type of oil and gas reservoir in the Huangling exploration area of the Triassic Yanchang Formation in the Ordos Basin.Due to sedimentation and diagenesis,it has poor physical properties and belongs to low-permeability tight sandstone reservoir.In order to further reveal the characteristics of shallow buried tight oil reservoir in the research area,260 samples from 14 wells were collected for testing and analysis.The petrological characteristics and microscopic pore throat characteristics of the reservoir were analyzed based on the measured data such as casting thin sections,energy spectrum,X-ray diffraction,scanning electron microscopy,high-pressure mercury injection,and constant velocity mercury injection.Combined with well logging data,the four-property relationship of the reservoir was studied,and a"four element"classification evaluation parameter suitable for the Huangling Shuanglong-Yaoping area was proposed to guide oil and gas exploration practices.The research result shows that rapid mixed source sedimentation,lack of sorting,and excessive rock debris are the fundamental reasons for the formation of the tight reservoir;Underdeveloped dissolution and later carbonate cementation intensified the densification of the reservoir.The shallow burial depth,low driving pressure,and thin average mainstream throat,as well as the development of multiple types of clay minerals,are the reasons for poor reservoir permeability.The overall reservoir properties are positively correlated with pore throat radius and negatively correlated with displacement pressure.Porosity is controlled by the average pore throat radius,while permeability is controlled by the mainstream throat radius.After standardizing the"four properties"of oil reservoir(acoustic time difference,resistivity,natural gamma,and oil saturation),a classification coefficientΨgreater than 1.1 is as the criterion for high-quality oil reservoirs.

关 键 词：致密油 储层特征 “四元”分类 黄陵探区 鄂尔多斯盆地 

分 类 号：TE112.23[石油与天然气工程—油气勘探]