勃利盆地七台河断陷煤层气富集特征及有利区优选  

Enrichment Characteristics of Coalbed Methane and Optimization of Favorable Areas in Qitaihe Fault Depression,Boli Basin

作　　者：张晓晴 康玉国 孙斌[3] 孙钦平[3] 杨青[3] Zhang Xiaoqing;Kang Yuguo;Sun Bin;Sun Qinping;Yang Qing(Natural Resources Survey Institute of Heilongjiang Province,Harbin 150036,China;China Coal Geology Group Co.,Ltd.,Beijing 100040,China;Research Institute of Petroleum Exploration and Development,Beijing 100083,China)

机构地区：[1]黑龙江省自然资源调查院,哈尔滨150036 [2]中煤地质集团有限公司,北京100040 [3]中国石油勘探开发研究院,北京100083

出　　处：《吉林大学学报（地球科学版）》2023年第4期1033-1047,共15页Journal of Jilin University：Earth Science Edition

基　　金：国家科技重大专项(2016ZX05041004-002);中国地质调查局项目(12120115008101)。

摘　　要：勃利盆地七台河断陷煤层气资源丰富,但勘探程度低,富集成藏规律和成藏机制认识不足,制约了勘探实践。本文基于对七台河断陷区煤层气地质条件的精细解剖,揭示了研究区煤层气富集特征及成藏机制。研究发现七台河断陷煤层气成藏条件良好,其中下白垩统城子河组煤层层数多、总厚度大,发育多个富煤中心,热演化程度较高,煤储层物性较好,煤层含气量总体西高东低,构造、水文、封盖等保存条件较好,具备良好的煤层气成藏基础,存在向斜-水力封堵型、断层封闭-水力封堵型、断层-多煤层自封闭型3种煤层气成藏模式,埋藏适中、缓—滞留水环境下的“逆断层封闭区”、“次级构造高点”和“煤层中部分层”是煤层气富集成藏有利部位。在此基础上,建立了多层次模糊数学煤层气选区评价模型,进行了有利区评价,优选出青龙山—桃山区、马场区等7个煤层气有利区。The Qitaihe fault depression in the Boli basin is rich in coalbed methane resources,but the exploration level is low,and the understanding of the enrichment and accumulation laws and mechanisms is insufficient,which restricts exploration practice.Based on a detailed dissection of the geological conditions of coalbed methane in the Qitaihe fault depression,this article reveals the enrichment characteristics and reservoir formation mechanism of coalbed methane in the study area.The study found that the coalbed methane reservoir in the Qitaihe fault depression has good conditions,with many coal seams in the Lower Cretaceous Chengzihe Formation,a large total thickness of coal seams,multiple developed coal rich centers,and a high degree of thermal evolution.The physical properties of coal reservoirs are favorable,and the gas content of coal seams is generally characterized by high in the west and low in the east.The structure,the hydrology,the sealing and other preservation conditions benefit coalbed methane reservoir formation.There are three types of models of coalbed methane reservoir formation,syncline-hydraulic sealing,fault sealing-hydraulic sealing,and fault-multi seam self-sealing.Under moderate burial depth and slow stagnant water environment,the reverse fault sealing area,secondary structural high point,and middle coal seam stratification are favorable locations for coalbed methane enrichment.On this basis,a multi-level fuzzy mathematics evaluation model for coalbed methane selection was established,and favorable areas were evaluated.Seven coalbed methane favorable areas were selected,including Qinglongshan-Taoshan district and Machang district.

关 键 词：勃利盆地 七台河断陷 煤层气 富集特征 成藏机制 成藏模式 多层次模糊数学 有利区优选 

分 类 号：P618.13[天文地球—矿床学] TE112.41[天文地球—地质学]