不同煤系源岩生烃特征的黄金管热模拟实验对比研究  

Study on the Hydrocarbon Generation Characteristics of Different Coaly Source Rocks by Gold-tube Pyrolysis Experiments

作　　者：毛榕[1,2] 米敬奎[2] 张水昌[2] 何坤[2] 

机构地区：[1]长江大学地球化学系,湖北荆州434023 [2]中国石油勘探开发研究院CNPC油气地球化学重点实验室,北京100083

出　　处：《天然气地球科学》2012年第6期1127-1134,共8页Natural Gas Geoscience

基　　金：国家重大专项(编号:2011ZX007-001)资助

摘　　要：对鄂尔多斯盆地同一地区侏罗系煤、煤系泥岩和炭质泥岩生烃全过程的模拟实验结果表明:不同种类煤系源岩热解生油特征存在较大的差异;与典型的湖相或海相源岩相比,这3种煤系源岩生油潜力都比较低。生油潜力最高的为煤系泥岩,其最大生油量约为20mg/gTOC,而煤和炭质泥岩的生油潜力几乎只有煤系泥岩的一半。因此,煤系源岩单独大规模形成油藏的可能性较低。煤岩、煤系泥岩及炭质泥岩最大生成烃类气体气量为184～212mL/gTOC,在3种源岩中煤的生气量最大,而煤系泥岩的最大生气量只有3m3/t岩石;煤和炭质泥岩生成气体的碳同位素相近,而煤系泥岩生成甲烷碳同位素值要比煤同温度生成的甲烷碳同位素值偏低3‰～5‰。3种源岩模拟生气实验结果表明:煤应该是煤成气的主要贡献者。From the simulation experiments on the hydrocarbon generation of Jurassic coal,coaly mudstone and carbon mudstone from Ordos basin,it is indicated that the oil generation characteristics of three coaly source rocks are distinct from each other in pyrolysis.The hydrocarbon generation potential of the three coal bearing source rocks were all relatively low compared to a typical lacustrine or marine source rock.Coaly mudstone had a highest amounts of oil yields with a maximum of about 20mg/gTOC,which is twice as that of coal and carbon mudstone.Hence,coal bearing source rocks seem impossible to form extensive oil reservoir.The maximum gas yields of coal,coaly mudstone and carbon mudstone is 184-212mL/gTOC.Wherein,coal had a highest amounts of gas yields in the three source rocks,the largest amount of that generated from coaly mudstone was less than 3m3/trock.The isotope distributions of hydrocarbon gases derived from coal and carbon mudstone were similar.The carbon isotope of methane from coaly mudstone is 3‰-5‰ lighter than that from coal at the same temperature.The results of simulation experiments on the gas yields from the three source rocks demonstrated that coal should be the dominant contributor for the accumulation of coal genetic gas.

关 键 词：煤系源岩 黄金管热模拟 生油潜力 稳定碳同位素 煤成气 

分 类 号：TE135[石油与天然气工程—油气勘探]