•  
  •  
 

Coal Geology & Exploration

Abstract

The Wangfu fault depression in the southern Songliao Basin is rich in coalbed methane (CBM) resources. However, CBM exploration in this area has been restricted by the low-level exploration of deep CBM and a lack of systematic studies on the geological characteristics of CBM, primary factors controlling CBM enrichment and accumulation, and the selection of favorable targets. Therefore, based on the systematical analysis of the geological characteristics of coal-bearing strata, this study identified the major factors controlling deep CBM accumulation, established the index system for favorable area selection, and predicted the favorable areas of CBM enrichment. The results show that: (1) Macroscopically, coals in the Huoshiling Formation in the Wangfu fault depression can be primarily categorized into bright and semi-bright coals, possessing the characteristics of low moisture, low volatile constituents, and low ash content. They exhibit vitrinite reflectance > 1.8%, average porosity of 5.01%, and average gas content of 21.80 m3/t (calculated based on well CS38). (2) The sedimentary environment, filled and leveled through volcanic eruption, of the Huoshiling Formation in the Wangfu fault depression is conducive to the formation of coal seams. Specifically, coal seams primarily occur between the double steep slope zones and in the shallow water areas of the central and eastern Wangfu fault depression, which were formed by the filling and leveling effects of volcanic eruption. In this manner, the coal formation mode featuring filling and leveling is formed. Additionally, the presence of large-area thick mudstone roofs and closed faults allow for CBM enrichment and preservation in the fault depression. (3) Class I favorable areas in the Wangfu fault depression predominantly occur in the northern and central parts of the fault depression, with coal seam thicknesses > 5m, fault throw <50 m, cover thicknesses > 80 m, and gas logging-derived total hydrocarbon values > 15%. These suggest great potential for exploration and exploitation. Classes Ⅱ and Ⅲ favorable areas are mainly found in the northern and southern parts of the fault depression, with coal seam thicknesses < 5m, cover thicknesses < 80 m, and gas logging-derived total hydrocarbon values < 15%. Weak-sealing or open faults and greatly different cover thicknesses pose risks to CBM exploration and exploration in these areas.

Keywords

Songliao Basin, Wangfu fault depression, deep coalbed methane, geological characteristic, favorable area evaluation

DOI

10.12363/issn.1001-1986.23.08.0517

Reference

[1] 聂志宏,时小松,孙伟,等. 大宁–吉县区块深层煤层气生产特征与开发技术对策[J]. 煤田地质与勘探,2022,50(3):193−200.

NIE Zhihong,SHI Xiaosong,SUN Wei,et al. Production characteristics of deep coalbed methane gas reservoirs in Daning–Jixian Block and its development technology countermeasures[J]. Coal Geology & Exploration,2022,50(3):193−200.

[2] 庚勐,陈浩,陈艳鹏,等. 第4轮全国煤层气资源评价方法及结果[J]. 煤炭科学技术,2018,46(6):64−68.

GENG Meng,CHEN Hao,CHEN Yanpeng,et al. Methods and results of the fourth round national CBM resources evaluation[J]. Coal Science and Technology,2018,46(6):64−68.

[3] 张道勇,朱杰,赵先良,等. 全国煤层气资源动态评价与可利用性分析[J]. 煤炭学报,2018,43(6):1598−1604.

ZHANG Daoyong,ZHU Jie,ZHAO Xianliang,et al. Dynamic assessment of coalbed methane resources and availability in China[J]. Journal of China Coal Society,2018,43(6):1598−1604.

[4] 杨兆彪,高为,秦勇,等. 贵州深部煤层气地质特征及其资源潜力[J/OL]. 煤炭学报,2023:1–15 [2023-09-01]. https://doi.org/10.13225/j.cnki.jccs.2023.0465.

YANG Zhaobiao,GAO Wei,QIN Yong,et al. Geological characteristics and resource potential of deep coalbed methane in Guizhou[J/OL]. Journal of China Coal Society,2023:1–15 [2023-09-01]. https://doi.org/10.13225/j.cnki.jccs.2023.0465.

[5] 李曙光,王成旺,王红娜,等. 大宁–吉县区块深层煤层气成藏特征及有利区评价[J]. 煤田地质与勘探,2022,50(9):59−67.

LI Shuguang,WANG Chengwang,WANG Hongna,et al. Reservoir forming characteristics and favorable area evaluation of deep coalbed methane in Daning–Jixian Block[J]. Coal Geology & Exploration,2022,50(9):59−67.

[6] 杨秀春,徐凤银,王虹雅,等. 鄂尔多斯盆地东缘煤层气勘探开发历程与启示[J]. 煤田地质与勘探,2022,50(3):30−41.

YANG Xiuchun,XU Fengyin,WANG Hongya,et al. Exploration and development process of coalbed methane in eastern margin of Ordos Basin and its enlightenment[J]. Coal Geology & Exploration,2022,50(3):30−41.

[7] 徐凤银,闫霞,李曙光,等. 鄂尔多斯盆地东缘深部(层)煤层气勘探开发理论技术难点与对策[J]. 煤田地质与勘探,2023,51(1):115−130.

XU Fengyin,YAN Xia,LI Shuguang,et al. Theoretical and technological difficulties and countermeasures of deep CBM exploration and development in the eastern edge of Ordos Basin[J]. Coal Geology & Exploration,2023,51(1):115−130.

[8] 郭绪杰,支东明,毛新军,等. 准噶尔盆地煤岩气的勘探发现及意义[J]. 中国石油勘探,2021,26(6):38−49.

GUO Xujie,ZHI Dongming,MAO Xinjun,et al. Discovery and significance of coal measure gas in Junggar Basin[J]. China Petroleum Exploration,2021,26(6):38−49.

[9] 叶建平,侯淞译,张守仁. “十三五”期间我国煤层气勘探开发进展及下一步勘探方向[J]. 煤田地质与勘探,2022,50(3):15−22.

YE Jianping,HOU Songyi,ZHANG Shouren. Progress of coalbed methane exploration and development in China during the 13th Five–Year Plan period and the next exploration direction[J]. Coal Geology & Exploration,2022,50(3):15−22.

[10] 齐东岩. 王府断陷火石岭组火山岩储层分布规律及预测研究[D]. 大庆:东北石油大学,2018.

QI Dongyan. The distribution and prediction of volcanic rocks reservoir in Huoshiling Formation of Wangfu Fault Depression,northeast China[D]. Daqing:Northeast Petroleum University,2018.

[11] 孙文铁,李忠慧,李忠诚,等. 断陷盆地次生气藏成藏主控因素及成藏模式:以王府断陷泉一段–登娄库组碎屑岩气藏为例[J]. 东北石油大学学报,2020,44(6):94−102.

SUN Wentie,LI Zhonghui,LI Zhongcheng,et al. Main controlling factors and accumulation model of secondary gas reservoirs in faulted basins:Taking the clastic gas reservoir from Quan 1 member to Denglouku Formation in Wangfu Fault Depression as an example[J]. Journal of Northeast Petroleum University,2020,44(6):94−102.

[12] 韩青林. 王府断陷小城子洼槽火石岭组致密储层特征[J]. 石油知识,2021(5):60−61.

HAN Qinglin. Tight reservoir characteristics of Huoshiling Formation in Xiaochengzi subsag of Wangfu Fault Depression[J]. Petroleum Knowledge,2021(5):60−61.

[13] 王宏语,李瑞磊,朱建峰,等. 陆相裂谷盆地构造沉积学特征:以松辽盆地伏龙泉断陷为例[J]. 现代地质,2019,33(6):1151−1162.

WANG Hongyu,LI Ruilei,ZHU Jianfeng,et al. Tectonic sedimentology characteristics of continental rift basin:Case study from Fulongquan Fault Depression of Songliao Basin[J]. Geoscience,2019,33(6):1151−1162.

[14] 曾凡成,张昌民,李忠诚,等. 断块型沉火山碎屑岩致密气藏有效储层控制因素及分布规律:以松辽盆地南部王府气田白垩系沙河子组为例[J]. 石油与天然气地质,2021,42(2):481−493.

ZENG Fancheng,ZHANG Changmin,LI Zhongcheng,et al. Controlling factors and distribution pattern of effective tight gas pools in blocky pyroclastic rocks in the Cretaceous Shahezi Formation in Wangfu gas field,southern Songliao Basin[J]. Oil & Gas Geology,2021,42(2):481−493.

[15] 杨丽,林荣达,李向宜. 松辽盆地东部构造带白垩系沉积演化特征研究[J]. 科学技术与工程,2011,11(27):6544−6549.

YANG Li,LIN Rongda,LI Xiangyi. Research of the sedimentary evolutionary characteristic in Cretaceous of eastern tectonic zone in Songliao Basin[J]. Science Technology and Engineering,2011,11(27):6544−6549.

[16] 马行陟,宋岩,柳少波,等. 中高煤阶煤储层吸附能力演化历史定量恢复:以鄂尔多斯盆地韩城地区为例[J]. 石油学报,2014,35(6):1080−1086.

MA Xingzhi,SONG Yan,LIU Shaobo,et al. Quantitative research on adsorption capacity evolution of middle–high rank coal reservoirs in geological history:A case study from Hancheng area in Ordos Basin[J]. Acta Petrolei Sinica,2014,35(6):1080−1086.

[17] 孙宪航,陈保东,张莉莉,等. 液化天然气BOG的计算方法与处理工艺[J]. 油气储运,2012,31(12):931−933.

SUN Xianhang,CHEN Baodong,ZHANG Lili,et al. BOG calculation method and processing technique of liquefied natural gas[J]. Oil & Gas Storage and Transportation,2012,31(12):931−933.

[18] 余琪祥,罗宇,曹倩,等. 准噶尔盆地东北缘深层煤层气勘探前景[J]. 天然气地球科学,2023,34(5):888−899.

YU Qixiang,LUO Yu,CAO Qian,et al. Exploration prospect of deep coalbed methane in the northeastern margin of Junggar Basin[J]. Natural Gas Geoscience,2023,34(5):888−899.

[19] 曲浩鑫,许浩,汤达祯,等. 基于低温氮吸附法的海拉尔盆地褐煤孔隙特征研究[J]. 中国煤炭,2018,44(10):52−59.

QU Haoxin,XU Hao,TANG Dazhen,et al. Study on pore characteristics of lignite in Hailar Basin based on low–temperature nitrogen adsorption method[J]. China Coal,2018,44(10):52−59.

[20] 俞秋明. 利用气测录井对含气显示层进行定量评价的方法探讨[J]. 科技情报开发与经济,2012,22(22):145−147.

YU Qiuming. Probe into the methods for conducting quantitative assessment on gas–bearing presentation layers by using gas–logging[J]. Sci–Tech Information Development and Economy,2012,22(22):145−147.

[21] 胡晓兵. 榆社武乡区块深部煤层气地质特征与有利区评价[D]. 北京:中国矿业大学,2022.

HU Xiaobing. Geological characteristics and favorable area evaluation of deep coalbed methane in Yushe–Wuxiang Block[D]. Beijing:China University of Mining and Technology,2022.

[22] 徐德信,李乐,程政. 黔西北某区块煤层气赋存规律影响因素分析[J]. 石化技术,2017,24(7):172−173.

XU Dexin,LI Le,CHENG Zheng. Analysis of influencing factors of coalbed methane occurrence law in a block in northwest Guizhou[J]. Petrochemical Industry Technology,2017,24(7):172−173.

[23] 黄一鹏. 天然气藏泥岩盖层封闭性研究现状[J]. 石化技术,2019,26(12):341.

HUANG Yipeng. Research status of sealing property of mudstone caprock in natural gas reservoir[J]. Petrochemical Industry Technology,2019,26(12):341.

[24] INGRAM G M,URAI J L. Top–seal leakage through faults and fractures:The role of mudrock properties[J]. Geological Society,1999,158(1):125−135.

[25] WELSH K E,DEARING J A,CHIVERRELL R C,et al. Testing a cellular modelling approach to simulating late–Holocene sediment and water transfer from catchment to lake in the French Alps since 1826[J]. Holocene,2009,19(5):785−798.

[26] FOSSEN H. Structural geology[M]. New York:Cambridge University Press,2010.

[27] 吕延防,万军,沙子萱,等. 被断裂破坏的盖层封闭能力评价方法及其应用[J]. 地质科学,2008,43(1):162−174.

LYU Yanfang,WAN Jun,SHA Zixuan,et al. Evaluation method for seal ability of cap rock destructed by faulting and its application[J]. Chinese Journal of Geology,2008,43(1):162−174.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.