沉积学报2025，Vol.43Issue(4)：1163-1177,15.DOI:10.14027/j.issn.1000-0550.2024.083
鄂尔多斯盆地西缘奥陶系乌拉力克组海相页岩气形成条件与勘探潜力
Formation Conditions and Exploration Potential for Marine Shale Gas from the Ordovician Wulalike Formation in the Western Ordos Basin
摘要
Abstract
[Objective]To investigate the geological conditions and exploration potential of marine shale gas in the Wulalike Formation,western Ordos Basin,and effectively guide the exploration of marine shale gas.[Methods]A comprehensive analysis of its organic geochemistry,XRD and FE-SEM,combined with the regional structure evolu-tion characteristics and thermal simulation experimentation,was conducted to determine the distribution of marine shale,hydrocarbon generation potential,reservoir properties,preservation conditions and exploration potential.[Re-sults](1)The thickness of strata in the Wulalike Formation varies greatly,from 10-80 m in the northern and central areas to more than 1 100 m in the south.The TOC of the Wulalike shale is between 0.10%and 1.40%,and the organ-ic matter is mainly Type I(sapropelic).The shales in the north and central areas are deeply buried and have under-gone a high degree of thermal evolution,bringing it to the gas generation stage now.The southern part was affected by the thrust of the western ordos basin,which generated both oil and gas.(2)Various types of pores are developed in the Wulalike shale(inter-and intragranular pores,microfractures and a small amount of organic matter pores).Al-though its overall porosity is lower than that of the Longmaxi shales of the Sichuan Basin,the content of brittle miner-al is high,microfractures are relatively well developed,and its permeability is better than in the Longmaxi shales.(3)In the western Ordos Basin,the underlying Kelimoli Formation is mainly limestone,and the overlying Lashi-zhong Formation is mainly shale with minor limestone content,which provide good sealing capability and favors shale gas enrichment.[Conclusions]The stratigraphic distribution,hydrocarbon potential,fracturing ability and preserva-tion conditions of the Wulalike Formation indicate that the southern area of the Tiekesumao Sag in the northern part and the western area of the Gufengzhuang Sag in the central part,both have good marine shale gas exploration poten-tial.关键词
海相页岩气/形成条件/勘探潜力/乌拉力克组/鄂尔多斯盆地西缘Key words
marine shale gas/formation conditions/exploration potential/Wulalike Formation/western Ordos Basin分类
天文与地球科学引用本文复制引用
黄军平,王菁,张才利,谭开俊,黄正良,史江龙,张艳,李相博,郭玮,冯明..鄂尔多斯盆地西缘奥陶系乌拉力克组海相页岩气形成条件与勘探潜力[J].沉积学报,2025,43(4):1163-1177,15.基金项目
中国石油天然气股份有限公司"十四五"前瞻性基础性重大科技项目(2021DJ1904) （2021DJ1904）
中国石油天然气股份有限公司油气和新能源分公司科技项目(2023YQX10101,2023YQX10105)Forward-looking Basic Strategic Technology Research Project,No.2021DJ1904 （2023YQX10101,2023YQX10105）
Technology Project of Oil&Gas and New Energy Branch,China National Petroleum Corporation,No.2023YQX10101,2023YQX10105 （）
