Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin
作者机构:Institute of Surface-Earth System ScienceSchool of Earth System ScienceTianjin UniversityTianjin 300072China Institute of Earth EnvironmentsChinese Academy of SciencesXi’an 710061China
出 版 物:《Acta Geologica Sinica(English Edition)》 (地质学报(英文版))
年 卷 期:2024年第98卷第1期
页 面:207-219页
核心收录:
学科分类:0202[经济学-应用经济学] 02[经济学] 020205[经济学-产业经济学] 0708[理学-地球物理学]
基 金:supported by the National Natural Science Foundation of China(Grant Nos.42150710532 and 42103048)
主 题:CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin
摘 要:The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological *** better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I *** calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal *** model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in *** spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin *** study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.