摘要
对中国8大含气盆地中的500多口气井开展天然气汞含量检测,对产自不同地区的2个煤样开展煤生烃热释汞模拟实验,并对采自鄂尔多斯盆地的11块岩心煤样进行汞含量检测。研究表明,中国煤型气中汞的分布具有煤型气汞含量总体远高于油型气、不同煤型气汞含量的分布很不均匀、煤型气汞含量总体随产层深度的增加而变大这3个特征。中国煤型气中的汞主要来自于气源岩,其主要证据除了煤型气汞含量远高于油型气、高含二氧化碳天然气的汞含量随二氧化碳含量的增加而下降和煤系具备形成高含汞天然气的物质基础外,煤生烃热释汞模拟实验揭示煤在热演化过程中可以形成较高的天然气汞含量,煤型气汞含量受气源岩温度和储集层硫化环境的控制。结合岩石圈物质循环过程和油气形成过程,中国煤型气中汞的形成过程可以划分为搬运和沉积、浅部埋藏、深部埋藏、保存和破坏等4个阶段。
The mercury content in natural gas samples from more than 500 gas wells in eight large gas bearing basins of China was tested,mercury release experiments on two coal samples from different areas were conducted,and the mercury content of 11 coal samples from different gas wells of Ordos Basin was tested.The mercury distribution of the coal derived gas has three features:The first is that mercury content of coal derived gas is generally much higher than that of oil derived gas,the second is that the coal derived gases from different fields vary widely in mercury content,the third is that the mercury content in coal derived gas increases with the increase of production layer depth.Mercury in coal derived natural gas mainly originates from the source rock.Besides three evidences,namely,coal derived gas mercury content is much higher than that of oil derived gas,mercury content of gas with high carbon dioxide content decreases with the increase of carbon dioxide content,and the coal bearing strata have the material base to generate natural gas with high mercury content,the pyrolysis experiment of two coal samples show that coal can produce natural gas with high mercury content during the process of thermal evolution.The mercury content of coal derived natural gas is controlled mainly by the temperature of source rock and the sulfur environment of reservoir.According to lithospheric material cycling process and oil-gas formation process,the formation of mercury in coal derived gas can be divided into four stages,transportation and deposition,shallow burial,deep burial,and preservation and destruction.
作者
李剑
韩中喜
严启团
王淑英
葛守国
LI Jian;HAN Zhongxi;YAN Qituan;WANG Shuying;GE Shouguo(Research Institute of Petroleum Exploration & Development,PetroChina,Beijing 100083,China;Key Laboratory of Gas Reservoir Formation and Development,CNPC,Langfang 065007,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2019年第3期443-449,共7页
Petroleum Exploration and Development
基金
国家科技重大专项"大型气田成藏机制
富集规律与勘探新领域"(2016ZX05007-003)
中国石油天然气股份有限公司重大专项"有机质全过程生气定量表征及天然气精细鉴别"(2016B-0601)
关键词
中国
煤型气
汞
气源岩
油型气
天然气成因
China
coal derived gas
mercury
gas source rock
oil derived gas
gas genesis
