重庆科技大学学报（自然科学版）2025，Vol.27Issue(5)：59-69,11.DOI:10.19406/j.issn.2097-4531.2025.05.008
鄂尔多斯盆地H地区长8段致密砂岩储层成岩演化研究
Study on Diagenetic Evolution of Tight Sandstone Reservoirs of Chang 8 Member in H Area,Ordos Basin
摘要
Abstract
Taking the H area in the Ordos Basin as the study area,this research disusses the diagenetic evolution stages and sequences of tight sandstone reservois.The Chang 8 reservoir in the H area is predominantly composed of tight sandstone,with rock types mainly being feldspathic litharenite and lithic arkose,characterized by high quartz content and moderate structural maturity.The reservoir pores are primarily composed of primary intergranular pores and mixed intergranular pores,exhibiting overall low porosity and ultra-low permeability characteristics,with small median pore-throat radius.Analysis of key stratigraphic parameters such as sand-to-shale ratio,porosity,and permeability in the H area reveals that the potential"sweet spot"is distributed in the middle of the channel where the sand body is well developed.Diagenetic studies show that compaction and cementation(carbonate and clay minerals)are the main factors for the tightness of the reservoirs in this area,while dissolution(feldspar,rock frag-ment dissolution)creates secondary porosity but has limited improvement on permeability.The evolution of the res-ervoirs successively undergoes the early diagenesis A stage(chlorite cementation and pore preservation),early dia-genesis B stage(organic acid dissolution and pore increase),and middle diagenesis A stage(carbonate cementation and tightness),with oil charging alternating with diagenetic processes.Effective reservoirs are controlled by the synergy of porosity,permeability and pore-throat,while the main controlling factors for high production need to be comprehensively analyzed in conjunction with other factors.关键词
鄂尔多斯盆地/长8段/致密砂岩/储层特征/成岩演化Key words
Ordos Basin/Chang 8 Member/tight sandstone/reservoir characteristics/diagenetic evolution分类
地质学引用本文复制引用
梁钰楷,陈斌,曹青..鄂尔多斯盆地H地区长8段致密砂岩储层成岩演化研究[J].重庆科技大学学报（自然科学版）,2025,27(5):59-69,11.基金项目
陕西省科技厅自然科学基金项目"有机质类型及热成熟度对页岩层系生排烃过程孔隙演化约束机制研究"(2023-JC-QN-0320) （2023-JC-QN-0320）
陕西省教育厅科研计划项目"基于岩心可视化模型的页岩孔隙介质超临界CO2-水-岩反应机理及物性演化规律研究"(23JK0595) （23JK0595）
