Geochemical characteristics and genesis of coalbed methane in Baode area

Authors

LI Yangbing, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
ZENG Lei, Chongqing Academy of Ecological and Environmental Science, Chongqing 401147, China; Chongqing Engineering Research Center of Contaminated Sites and Groundwater Environment Sustainable Remediation, Chongqing 401147, ChinaFollow
HU Weiqiang, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
CHEN Xin, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
MA Litao, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
LIU Cheng, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
HUANG Ying, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China
QIAO Fang, CNOOC Energy Technology-Drilling & Production Co., Tianjin 300452, China

Abstract

In order to find out the geochemical characteristics and origins of coalbed methane(CBM)in Baode area, coal, CBM and water samples were collected, gas component analysis, quality detection of CBM well-produced water and stable isotope analysis were carried out. The results show that CH₄ is the main hydrocarbon gas in CBM composition and its volume fraction ranges from 88.60% to 97.59%; a small amount of ethane is contained, and the volume fraction is only 0.01%-0.14%. The drying coefficient is greater than 0.99, the CBM belongs to the extremely dry CBM. The non-hydrocarbon components mainly contain CO₂ and N₂, of which the CO₂ volume fraction ranges from 1.74% to 7.61% and N₂ volume fraction ranges from 0.04% to 8.18%. CBM δ¹³C(CH₄) value is between –56.8‰ and –47.7‰, the δ¹³C(CO₂) value lies between –6.6‰ and 13.9‰, the δD(CH₄) value is between –252.6‰ and –241.6‰.The water produced from coal seam is weakly alkaline, belonging to NaHCO₃ type water, which is similar to the ion composition, salinity, value of δD(H₂O) and δ¹⁸O(H₂O) of surface water, and the recharge from surface water is conducive to the proliferation of CH₄-producing bacteria and the formation of secondary biogas. It is generally believed that CBM in the study area is a mixture of thermal and biogenic gas, formed mainly through carbon dioxide reduction, and “lightened” due to coal seam desorption, diffusion and migration, water dissolution and secondary biological action. The research results provide guidance for subsequent CBM exploration and development.

Keywords

Baode area, coalbed methane, geochemistry, thermogenesis, biogenesis, isotope

DOI

10.3969/j.issn.1001-1986.2021.02.017

Recommended Citation

LI Yangbing, ZENG Lei, HU Weiqiang, et al. (2021) "Geochemical characteristics and genesis of coalbed methane in Baode area," Coal Geology & Exploration: Vol. 49: Iss. 2, Article 18.
DOI: 10.3969/j.issn.1001-1986.2021.02.017
Available at: https://cge.researchcommons.org/journal/vol49/iss2/18

Reference

[1] 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. ZHAO 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.

[2] 马行陟,宋岩,柳少波,等. 鄂尔多斯盆地东缘韩城地区煤层气地球化学特征及其成因[J]. 天然气工业,2011,31(4):17-20. MA Xingzhi,SONG Yan,LIU Shaobo,et al. Origins and geochemical characteristics of coalbed methane in Hancheng,Eastern Ordos Basin[J]. Nature Gas Industry,2011,31(4):17-20.

[3] 李贵红,张泓. 鄂尔多斯盆地东缘煤层气成因机制[J]. 中国科学:地球科学,2013,43(8):1359-1364. LI Guihong,ZHANG Hong. The origin mechanism of coalbed methane in the eastern edge of Ordos Basin[J]. Science China:Earth Sciences,2013,43(8):1359-1364.

[4] 陈跃,马东民,方世跃,等. 构造和水文地质条件耦合作用下煤层气富集高产模式[J]. 西安科技大学学报,2019,39(4):644-655. CHEN Yue,MA Dongmin,FANG Shiyue,et al. Enrichment and high-yield models of coalbed methane influenced by geologic structures and hydrologic conditions[J]. Journal of Xi'an University of Science and Technology,2019,39(4):644-655.

[5] 聂志宏,巢海燕,刘莹,等. 鄂尔多斯盆地东缘深部煤层气生产特征及开发对策:以大宁-吉县区块为例[J]. 煤炭学报,2018,43(6):1738-1746. NIE Zhihong,CHAO Haiyan,LIU Ying,et al. Development strategy and production characteristics of deep coalbed methane in the east Ordos Basin:Taking Daning-Jixian block for example[J]. Journal of China Coal Society,2018,43(6):1738-1746.

[6] 陈博,汤达祯,林文姬,等. 基于地质建模的保德Ι单元煤层气井产能响应特征[J]. 煤田地质与勘探,2020,48(5):53-63. CHEN Bo,TANG Dazhen,LIN Wenji,et al. Geological modeling-based productivity response characteristics of the CBM well in Baode unit Ι[J]. Coal Geology & Exploration,2020,48(5):53-63.

[7] 田文广,汤达祯,王志丽,等. 鄂尔多斯盆地东北缘保德地区煤层气成因[J]. 高校地质学报,2012,18(3):479-484. TIAN Wenguang,TANG Dazhen,WANG Zhili,et al. Origin of coalbed methane in Baode,northeastern Ordos Basin[J]. Geological Journal of China Universities,2012,18(3):479-484.

[8] 李勇,孟尚志,吴鹏,等. 煤层气成藏机理及气藏类型划分:以鄂尔多斯盆地东缘为例[J]. 天然气工业,2017,37(8):22-30. LI Yong,MENG Shangzhi,WU Peng,et al. Accumulation mechanisms and classification of CBM reservoir types:A case study from the eastern margin of the Ordos Basin[J]. Nature Gas Industry,2017,37(8):22-30.

[9] 刘晓鹏,赵会涛,闫小雄,等. 克拉通盆地致密气成藏地质特征与勘探目标优选:以鄂尔多斯盆地上古生界为例[J]. 天然气地球科学,2019,30(3):331-343. LIU Xiaopeng,ZHAO Huitao,YAN Xiaoxiong,et al. The geological characteristics of tight sandstone gas and exploration target evaluation in the Craton Basin:Case study of the Upper Paleozoic of Ordos Basin[J]. Natural Gas Geoscience,2019,30(3):331-343.

[10] 胡维强,赵靖舟,李军,等. 鄂尔多斯盆地西南部上古生界烃源岩特征及其对天然气藏形成与分布的控制作用[J]. 天然气地球科学,2015,26(6):1068-1075. HU Weiqiang,ZHAO Jingzhou,LI Jun,et al. Hydrocarbon source rocks characteristics and its controls on formation and distribution of gas of Upper Paleozoic in southwest Ordos Basin[J]. Natural Gas Geoscience,2015,26(6):1068-1075.

[11] 胡维强,李洋冰,陈鑫,等. 鄂尔多斯盆地临兴地区上古生界天然气成因及来源[J]. 天然气地球科学,2020,31(1):26-36. HU Weiqiang,LI Yangbing,CHEN Xin,et al. Origin and source of natural gas in the Upper Paleozoic in Linxing area,Ordos Basin[J]. Natural Gas Geoscience,2020,31(1):26-36.

[12] 巢海燕,王延斌. 鄂尔多斯盆地东南缘临汾区块煤层气成因及其影响[J]. 煤炭学报,2016,41(7):1769-1777. CHAO Haiyan,WANG Yanbin. Origin of coalbed methane and its influence in Linfen,southeastern Ordos Basin[J]. Journal of China Coal Society,2016,41(7):1769-1777.

[13] 邹才能,杨智,黄士鹏,等. 煤系天然气的资源类型、形成分布与发展前景[J]. 石油勘探与开发,2019,46(3):433-442. ZOU Caineng,YANG Zhi,HUANG Shipeng,et al. Resource types,formation,distribution and prospects of coal-measure gas[J]. Petroleum Exploration and Development,2019,46(3):433-442.

[14] 徐占杰,刘钦甫,郑启明,等. 沁水盆地北部太原组煤层气碳同位素特征及成因探讨[J]. 煤炭学报,2016,41(6):1467-1475. XU Zhanjie,LIU Qinfu,ZHENG Qiming,et al. Origins and carbon isotopic composition of coalbed methane and carbon dioxide from Taiyuan Formation,northern Qinshui Basin,China[J]. Journal of China Coal Society,2016,41(6):1467-1475.

[15] 王勃,姚红星,王红娜,等. 沁水盆地成庄区块煤层气成藏优势及富集高产主控地质因素[J]. 石油与天然气地质,2018,39(2):366-372. WANG Bo,YAO Hongxing,WANG Hongna,et al. Favorable and major geological controlling factors for coalbed methane accumulation and high production in the Chengzhuang block,Qingshui Basin[J]. Oil & Gas Geology,2018,39(2):366-372.

[16] 马东民,王传涛,夏玉成,等. 大佛寺井田煤层气井压裂参数优化方案[J]. 西安科技大学学报,2019,39(2):263-269. MA Dongmin,WANG Chuantao,XIA Yucheng,et al. Optimization program of fracturing parameters for coalbed methane wells in Dafosi minefield[J]. Journal of Xi'an University of Science and Technology,2019,39(2):263-269.

[17] 杨帆,杨秀春,姜波,等. 保德地区构造特征及其构造应力场分析[J]. 煤炭科学技术,2014,42(7):92-97. YANG Fan,YANG Xiuchun,JIANG Bo,et al. Analysis on tectonic characteristics and tectonic stress field in Baode area[J]. Coal Science and Technology,2014,42(7):92-97.

[18] 陈红东,姜波,屈争辉,等. 临汾与保德地区构造差异性特征及其对煤层含气性的控制[J]. 煤炭学报,2014,39(3):510-517. CHEN Hongdong,JIANG Bo,QU zhenghui,et al. Diversity structural characteristics and control action on coal bed gas content in Linfen and Baode area[J]. Journal of China Coal Society,2014,39(3):510-517.

[19] 李勇,汤达祯,方毅,等. 鄂尔多斯盆地东缘煤层气甲烷碳同位素分布及成因[J]. 中国科学:地球科学,2014,44(9):1940-1947. LI Yong,TANG Dazhen,FANG Yi,et al. Distribution of stable carbon isotope in coalbed methane from the east margin of Ordos Basin[J]. Science China:Earth Sciences,2014,44(9):1940-1947.

[20] 沈玉林,秦勇,申建,等. 鄂尔多斯盆地东缘上古生界煤系叠置含气系统发育的沉积控制机理[J]. 天然气工业,2017,37(11):29-35. SHEN Yulin,QIN Yong,SHEN Jian,et al. Sedimentary control mechanism of the superimposed gas bearing system development in the Upper Paleozoic coal measures along the eastern margin of the Ordos Basin[J]. Natural Gas Industry,2017,37(11):29-35.

[21] 王越,陈世悦,梁绘媛,等. 鄂尔多斯盆地保德地区上古生界沉积相与沉积演化特征[J]. 沉积学报,2016,34(4):775-784. WANG Yue,CHEN Shiyue,LIANG Huiyuan,et al. Sedimentary facies and their evolution in the Upper Paleozoic of Baode area,Ordos Basin[J]. Acta Sedimentologica Sinica,2016,34(4):775-784.

[22] 平立华,郭英海,李壮福,等. 鄂尔多斯盆地保德地区太原组桥头砂岩沉积特征及成因[J]. 天然气地球科学,2006,17(6):797-801. PING Lihua,GUO Yinghai,LI Zhuangfu,et al. Sedimentary characters and origin of Qiaotou sandstone in the Taiyuan Formation,Baode area of Ordos Basin[J]. Natural Gas Geoscience,2006,17(6):797-801.

[23] 侯中帅,陈世悦,王越,等. 鄂尔多斯盆地东缘保德地区上古生界层序地层与沉积相特征[J]. 古地理学报,2018,20(2):231-243. HOU Zhongshuai,CHEN Shiyue,WANG Yue,et al. Characteristics of sequence stratigraphy and sedimentary facies of the Upper Paleozoic in Baode area,eastern margin of Ordos Basin[J]. Journal of Palaeogeography,2018,20(2):231-243.

[24] LI Qingguang,JU Yiwen,BAO Yuan,et al. Composition,origin,and distribution of coalbed methane in the Huaibei coalfield,China[J]. Energy and Fuels,2015,29(2):546-555.

[25] SONG Yan,LIU Shaobo,ZHANG Qun,et al. Coalbed methane genesis,occurrence and accumulation in China[J]. Petroleum Science,2012,9(3):269-280.

[26] 琚宜文,李清光,颜志丰,等. 煤层气成因类型及其地球化学研究进展[J]. 煤炭学报,2014,39(5):806-815. JU Yiwen,LI Qingguang,YAN Zhifeng,et al. Origin types of CBM and their geochemical research progress[J]. Journal of China Coal Society,2014,39(5):806-815.

[27] 侯光才,张茂省. 鄂尔多斯盆地地下水勘查研究[M]. 北京:地质出版社,2008. HOU Guangcai,ZHANG Maosheng. Exploration of groundwater in Ordos Basin[M]. Beijing:Geological Publishing House,2008.

[28] 田文广,邵龙义,孙斌,等. 保德地区煤层气井产出水化学特征及其控气作用[J]. 天然气工业,2014,34(8):15-19. TIAN Wenguang,SHAO Longyi,SUN Bin,et al. Chemical behaviors of produced water from CBM wells in the Baode area,Shanxi,China,and their control on gas accumulation[J]. Nature Gas Industry,2014,34(8):15-19.

[29] 陶俊杰,申建,王金月,等. 二连盆地吉尔嘎朗图凹陷煤层气成因类型及勘探方向[J]. 高校地质学报,2019,25(2):295-301. TAO Junjie,SHEN Jian,WANG Jinyue,et al. Genetic types and exploration prospect of coalbed methane in Jiergalangtu depression,Erlian Basin[J]. Geological Journal of China Universities,2019,25(2):295-301.

[30] 刘会虎,兰天贺,胡宝林,等. 淮南潘集外围深部煤层气地球化学特征及成因[J]. 煤炭学报,2018,43(2):498-506. LIU Huihu,LAN Tianhe,HU Baolin,et al. Geochemical characteristics and its origins of CBM in deep-seated coal seam around Panji mining area of Huainan[J]. Journal of China Coal Society,2018,43(2):498-506.

[31] STAHL W J. Carbon and nitrogen isotopes in hydrocarbon research and exploration[J]. Chemical Geology,1972,2(2):121-149.

[32] SCHOELL M. Genetic characterization of natural gas[J]. AAPG Bulletin,1983,67:2225-2238.

[33] 徐永昌,沈平,刘文汇,等. 一种新的天然气成因类型-生物一热催化过渡带气[J]. 中国科学B辑,1990(9):975-980. XU Yongchang,SHEN Ping,LIU Wenhui,et al. A new genetic type of natural gas-bio-thermal catalytic transition zone[J]. Science in China(Series B),1990(9):975-980.

[34] 沈平,徐永昌. 中国陆相成因天然气同位素组成特征[J]. 地球化学,1991(2):144-152. SHEN Ping,XU Yongchang. The isotopic composition of natural gases from continental sediments in China[J]. Geochimica,1991(2):144-152.

[35] 戴金星. 各类烷烃气的鉴别[J]. 中国科学B辑,1992,22(2):185-193. DAI Jinxing. Identification of various alkane gases[J]. Science in China(Series B),1992,22(2):185-193.

[36] 陈安定,张文正,徐永昌. 沉积岩成烃热模拟实验产物的同位素特征及应用[J]. 中国科学B辑,1993,23(2):209-217. CHEN Anding,ZHANG Wenzheng,XU Yongchang. Isotope characteristics and application of products from thermal simulation experiments of sedimentary rock hydrocarbon formation[J]. Science in China(Series B),1993,23(2):209-217.

[37] 刘文汇,刘全有,徐永昌,等. 天然气地球化学数据的获取及应用[J]. 天然气地球科学,2003,14(4):21-29. LIU Wenhui,LIU Quanyou,XU Yongchang,et al. The gaining and applying of data in natural gas geochemistry study[J]. Natural Gas Geoscience,2003,14(4):21-29.

[38] WHITICAR M J. Carbon and hydrogen isotope systematics of bacterial formation end oxidation of methane[J]. Chemical Geology,1999,161:291-314.

[39] 于振锋,郝春生,杨昌永,等. 阳泉矿区寺家庄井田太原组煤层气地球化学特征及成因[J]. 煤田地质与勘探,2019,47(3):91-96. YU Zhenfeng,HAO Chunsheng,YANG Changyong,et al. Genesis and geochemical characteristics of coalbed methane from Taiyuan Formation in Sijiazhuang mine field of Yangquan mining area[J]. Coal Geology & Exploration,2019,47(3):91-96.

[40] 李建军,白培康,毛虎平,等. 郑庄-胡底煤层气地球化学特征及成因探讨[J]. 煤炭学报,2014,39(9):1802-1811. LI Jianjun,BAI Peikang,MAO Huping,et al. Analysis of geochemistry characteristics and its origin of CBM in Zhengzhuang and Hudi blocks[J]. Journal of China Coal Society,2014,39(9):1802-1811.

[41] 王晓锋,刘文汇,徐永昌,等. 水介质对气态烃形成演化过程氢同位素组成的影响[J].中国科学:D辑地球科学,2012,42(1):103-110. WANG Xiaofeng,LIU Wenhui,XU Yongchang,et al. Influences of water media on the hydrogen isotopic composition of natural gas/methane in the processes of gaseous hydrocarbon generation and evolution[J]. Science in China:Series D Earth Science,2012,42(1):103-110.

[42] 王晓锋,刘文汇,徐永昌,等. 不同成因天然气的氢同位素组成特征研究进展[J]. 天然气地球科学,2006,17(2):163-169.WANG Xiaofeng,LIU Wenhui,XU Yongchang,et al. The hydrogen isotopic composition of natural gases generated from different pathway[J]. Natural Gas Geoscience,2006,17(2):163-169.

[43] WHITICAR M J,FABER E,SCHOELL M. Biogenic methane formation in marine and freshwater environments:CO₂ reduction vs. acetate fermentation-isotope evidence[J]. Geochimica et Cosmochimica Acta,1986,50:693-709.

[44] JENDEN P D,KAPLAN I R. Comparison of microbial gases from the middle America Trench and Scripps submarine canyon:Implications for the origin of natural gas[J]. Applied Geochemistry,1986,1(6):631-646.