鄂尔多斯盆地中东部本溪组致密砂岩储层特征及有利层段优选  

Characteristics and favorable intervals selection of tight sandstone reservoirs in Benxi Formation, central-eastern Ordos Basin

作　　者：黄道军[1] 李新虎[2] 刘燕[1] 张辉[1] HUANG Daojun;LI Xinhu;LIU Yan;ZHANG Hui(Department of Exploration,Petro China Changqing Oilfield Company,Xi’an 710018,China;College of Geology and Environment,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [2]西安科技大学地质与环境学院,陕西西安710054

出　　处：《西安科技大学学报》2023年第1期109-118,共10页Journal of Xi’an University of Science and Technology

基　　金：国家自然科学基金项目(41702136);陕西省自然科学基础研究项目(2019JQ-308)。

摘　　要：鄂尔多斯盆地中东部本溪组发育厚层含气的致密砂岩储层,开展其储层特征及有利层段研究,对于深化鄂尔多斯盆地中东部本溪组储层地质认识和有利勘探层段选择具有重要的理论和指导意义。基于岩石薄片、X射线衍射、扫描电镜等分析测试以及常规压汞、常规物性、核磁共振等多种岩石物理分析,综合开展了储层岩石学、孔隙结构、物性、含气性特征研究;结合烃源岩品质以及储层可压性、气测曲线特征开展有利层段优选。结果表明:鄂尔多斯盆地中东部本溪组砂岩以石英砂岩和岩屑石英砂岩为主,储集空间以原生粒间孔和次生溶孔为主;砂岩具有低孔、低渗、颗粒偏细等特点,属高排驱压力-微喉道型和物性较差的致密砂岩储层。储层具有高杨氏模量、低泊松比、石英等脆性矿物含量较高的特点,使储层易压裂改造;下伏于8号煤层且发育良好的致密砂岩储层为本溪组重要的气层,邻近灰岩的上覆致密砂岩储层含水性增强。研究成果为鄂尔多斯盆地中东部本溪组致密砂岩气的规模勘探与效益开发提供地质依据。Thick gas-bearing tight sandstone reservoirs are developed in Benxi Formation in the central-eastern Ordos Basin, and the study of its reservoir characteristics and favorable intervals has important theoretical and guiding significance for deepening the geological understanding of Benxi Formation reservoirs in the central-eastern Ordos Basin and selecting the favorable exploration intervals.Based on the analytical methods including petrographic thin section, X-ray diffraction, scanning electron microscopy, and the rock physical experiments including conventional mercury intrusion, conventional physical properties and nuclear magnetic resonance, the reservoir characteristics of petrological, pore structure, physical properties and gas-bearing properties were comprehensively examined.In light of the characteristics of hydrocarbon source rock quality and the type of the whole hydrocarbon curve, the reservoir favorable intervals selection was carried out.The research results show that the tight sandstone of Benxi Formation in the central-eastern Ordos Basin is mainly quartz sandstone and lithic quartz sandstone, and the rock space is dominated by primary intergranular pores and secondary dissolution pores.The formation was classified to tight sandstone reservoir with high displacement pressure, micro throat and poor physical properties by low porosity, low permeability and fine particles.The reservoir is characterized by high Young’s modulus, low Poisson’s ratio, high content of brittle minerals like quartz, which makes it easy to fracture and reform of reservoir.The well-developed tight sandstone reservoir underlying the Coal Seam 8#is an important gas-bearing reservoir in Benxi Formation.The water-bearing capacity of the overlying tight sandstone reservoir adjacent to limestone is enhanced.The research results provide a geological basis for large-scale exploration and beneficial development of gas-bearing tight sandstone in Benxi Formation in central-eastern Ordos Basin.

关 键 词：致密砂岩 储层特征 有利层段 本溪组 鄂尔多斯盆地 

分 类 号：TE135.1[石油与天然气工程—油气勘探]