海相油气地质2026，Vol.31Issue(3)：289-300,12.DOI:10.3969/j.issn.1672-9854.2026.03.007
二连盆地天然气地质条件、资源潜力与勘探方向
Geological conditions,resource potential,and exploration directions of natural gas in the Erlian Basin
摘要
Abstract
The Erlian Basin is mainly focused on oil exploration,with a relatively low degree of natural gas exploration.Natural gas has been discovered in the Permian,Jurassic and Cretaceous strata.Based on geochemical analysis of the gas components and carbon isotopic compositions,the natural gas in the Erlian Basin can be classified into four genetic types:biogenic gas,oil-type gas,coal-type gas,and non-hydrocarbon gas.Gas maturity assessments and gas-source correlations reveal that the basin hosts multiple sets of gas-prone source rocks,including immature to low-mature coal and dark mudstone in the shallow Saihantala Formation of the Cretaceous,mature to high-mature dark mudstone in the middle-deep Arshan Formation of the Cretaceous,low-mature to high-mature coal-measure source rocks of the Jurassic,and mature to over-mature dark mudstone of the Carboniferous-Permian.The coal seams are thin but widely distributed,while the dark mudstones are nearly 1 000 m thick and extensively developed in the basin,with organic matter types of II2-III,providing a source rock foundation for natural gas generation.Natural gas accumulates in near-source structural highs,and there are five main favorable reservoir-seal assemblages,based on which accumulation models for shallow biogenic gas,mid-deep oil and gas,and deep natural gas are established.Using the genetic method and analogy method,the natural gas resources are evaluated.The calculated in-place resources are 2 411×108 m3 for the Carboniferous-Permian,2 311×108 m3 for the Jurassic,707×108 m3 for the Cretaceous Arshan Formation in four sags,and 1 425×108 m3 for the Cretaceous Saihantala Formation and Teng-2 member.Overall,favorable exploration targets include the near-source structural highs of the mature Arshan Formation in the sags,and the shallow biogenic gas traps of the Cretaceous Saihantala Formation and Teng-2 member.The Carboniferous-Permian in the eastern sags,and the Jurassic in inherited sags such as Honghaorshute,Aqituwula,and Gaolihan,have good exploration prospects.关键词
天然气成因类型/成藏条件/成藏模式/资源潜力/勘探方向/二连盆地Key words
genetic types of natural gas/natural gas accumulation conditions/reservoir formation model/resource poten-tial/exploration direction/Erlian Basin分类
能源科技引用本文复制引用
钟雪梅,高歌,师玉雷,王帅,张国伟,庞秋菊,金娟娟,江涛..二连盆地天然气地质条件、资源潜力与勘探方向[J].海相油气地质,2026,31(3):289-300,12.基金项目
本文受中国石油天然气股份公司科技专项"中石油'十四五'油气资源评价"(编号:2023YQX20106)和"中石油油气成藏远景区划"(编号:QGYQCCQH2025-1)联合资助 （编号:2023YQX20106）
