中国地质2025，Vol.52Issue(6)：2014-2024,11.DOI:10.12029/gc20240529003
鄂尔多斯盆地延安东部地区本溪组深部煤层气成藏条件与勘探潜力
Accumulation conditions and exploration potential of deep coalbed methane in Benxi Formation,Eastern Yan'an area,Ordos Basin
摘要
Abstract
This paper is the result of oil and gas exploration engineering. [Objective]The Benxi Formation coal seams in the eastern Yan'an area of Ordos Basin are characterized by table distribution,sadvanced thermal maturity and high gas content.This study evaluates the gas accumulation conditions and resource potential of deep coalbed methane in the Benxi Formation,aiming to provide guidance for future exploration and to further enrich the geological theory of deep coalbed methane accumulation.[Methods]Based on a comprehensive review of deep coalbed methane exploration results in China,this study utilizes abundant drilling data and coal core analysis from the eastern Yan'an area to analyze the distribution,reservoir characteristics,coal quality,and gas-bearing properties of the Benxi Formation coal seams,systematically evaluating their accumulation conditions and exploration potential.[Results](1)The 8#coal seam of the Benxi Formation is widely distributed in the eastern Yan'an area,with an average thickness of 4 m.The coal lithotypes are primarily bright coal and semi-bright coal,with a rank reaching lean coal to anthracite.The average gas content is 16.8 m3/t,indicating favorable conditions for deep coalbed methane accumulation;(2)The study area covers 10500 km2,with an estimated coalbed methane resource of 970 billion cubic meters and an average resource abundance of 0.92 × 108 m3/km2;(3)Based on six indicators such as coal seam thickness,gas content,and preservation conditions,criteria for selecting favorable areas for deep coalbed methane were established.This resulted in the identification of 147.9 km2 as first-class favorable areas and 1138 km2 as second-class favorable areas;(4)Following the favorable area selection,a review of existing wells was conducted.Four vertical wells,including Well C7,were selected for fracturing and production testing,achieving post-fracturing gas rates ranging from 1000 m3/d to 1700 m3/d.[Conclusions]The Benxi Formation in the eastern Yan'an area possesses significant exploration potential for deep coalbed methane and is expected to become a successor resource for stabilizing gas field production.Future work should focus on detailed geological studies,classified evaluation,selection of optimal production zones,and advancing the exploration and development process for deep coalbed methane.关键词
深部煤层气/成藏条件/勘探潜力/油气勘查工程/延安东部地区/鄂尔多斯盆地Key words
deep coalbed methane/accumulation conditions/exploration potential/oil and gas exploration engineering/eastern Yan'an/Ordos Basin分类
天文与地球科学引用本文复制引用
孙建博,杨钊,胡登平,罗腾跃,林进,孟祥振,赵伟波,张建锋,王振川,蒲泊伶,刘刚,姜磊..鄂尔多斯盆地延安东部地区本溪组深部煤层气成藏条件与勘探潜力[J].中国地质,2025,52(6):2014-2024,11.基金项目
陕西延长石油(集团)有限责任公司项目"延安东部地区深层煤层气富集成藏规律与有利开发目标评价"(ycsy2024jcyj-B-04)资助. Supported by the project of Shaanxi Yanchang Petroleum(Group)Co.,Ltd."Yan'an Eastern Region of Deep Coalbed Methane Accumulation Law and Favorable Development Target Evaluation"(No.ycsy2024jcyj-B-04). （集团）
