关于冀中坳陷煤成气的探讨——与王雪平等同志商榷

AN APPROACH ON GASES DERIVED FROM COAL MEASURES IN JIZHONG DEPRESSION——A Discussion with Mr.Wang Xueping et al

戴金星

Dai Jingxing

石油工业部石油勘探开发科学研究院

Research Institute of Petroleum Exploration and Development, Ministry of Petroleum Industry

本文主要针对王雪平等[1]提出的“冀中坳陷天然气源主要为油型气”进行讨论.作者通过有关资料的对比和研究,认为冀中坳陷的天然气既有油型气又有煤成气,且以石炭-二叠系为主要源岩.从目前探明的天热气储量来看也是如此,99.3%的天然气集中分布于有二叠系分布的奥陶系和石炭-二叠系潜山中,源于第三系的天然气仅占探明储量的0.7%.

According to the σ13C values of methane,the gases in Jizhong Depression can be divided into three groups as follows.-55‰ for shallow biogenetic gas,-53.5‰— -40.4‰ for the gas derived from oil,and -39.6‰— -33.9‰ for the gas derived from coal measures.The 40Ar/36Ar values of coal measure gas are similar to those of oil-derived gas and they may be formed in the late stage of gas generation.The coal measure gas in the depression mainly formed by secondary gas generation as the depression resubsided in Tertiary time.It is evident that 99,3 percent of the presently proved gas reserves is discovered at Permo-Carboniferous buried hills,and Ordovician buried hills with Permo-Carboniferous cover while only 0.7 percent of the proved gas reserves is discovered in Tertiary systems.

https://doi.org/10.11781/sysydz198802189