摘要
阿克1气藏是塔西南前陆区喀什凹陷油气勘探上获得重大突破的工业性气藏。采用金管封闭体系热模拟实验和GC-IRMS碳同位素测定,结合运用GOR-ISOTOPEKINETICS专用软件,推导出了塔西南前陆区烃源岩(煤和泥岩)热解生成甲烷的碳同位素动力学参数。该区侏罗系煤、侏罗系泥岩和二叠系泥岩的平均活化能分别为225.86kJ/mol、194.03kJ/mol和223.45kJ/mol,甲烷(12CH4)的指前因子各为1.00×1014s-1、1.00×1013s-1、1.00×1014s-1。在此基础上,利用碳同位素动力学计算结果,并结合地质背景,进一步探讨了阿克1气藏天然气的来源,为天然气定量评价提供了新思路。阿克1气藏天然气为烃源岩过成熟阶段的烃产物,属于混源气,主要捕获了Ro为2.0%～3.6%阶段的天然气;其气源区包括喀什凹陷中心和阿克1井推覆体下盘,主力气源岩是石炭系烃源岩。
The Ake 1 gas pool is a commercial gas reservoir that has made great breakthrough for oil and gas exploration in the Kashi Sag of the southwestern foreland region, Tarim Basin. By using the thermal simulation experiment of the closed gold-tube system and the measurement of GC-IRMS carbon isotope, combined with the GOR-ISOTOPE KINETICS specific software, the carbon isotopic kinetic parameters of methane generated from source rocks in the Southwestern Foreland Region, Tarim Basin are obtained. The average activation energies of Jurassic coal, Jurassic mudstone and Permian mudstone samples selected from the Southwestern Foreland Region of the Tarim Basin are 225.86 kJ/mol, 194.03 kJ/mol, and 223.45 kJ/mol, respectively. The prefactor of their methane （^12CH4） are 1.00 x 10^14 s^-1, 1.00 x 10^13s^-1, and 1.00 x 10^14s^-1. Based on the above researches,combined with the geological background, the origin of natural gas from the Ake 1 gas pool is further discussed by using the results of carbon isotope kinetic calculation. This provided a new thought for quantitatively evaluating the origin of natural gas. It is suggested that natural gas of the Ake 1 gas pool was the evolution product of over-matured source rocks, and belonged to the mixed gas, the maturity （ R°） of which is 2.0% ～3.6%. The gas source kitchen of the Ake 1 gas pool included the center of Kashi Sag and the drop plate of Well Ake 1, the main gas of which was derived from Carboniferous source rock.
出处
《地球化学》
CAS
CSCD
北大核心
2005年第5期525-532,共8页
Geochimica
基金
国家"十五"重点科技攻关项目(2001BA605A02-03-01和2004BA616A02-01-01)
中国博士后科学基金(2002031282)
国家自然科学基金(40072043)
有机地球化学国家重点实验室开放基金(OGL-200403)~~
关键词
天然气成因
碳同位素动力学
热解实验
烃源岩
气源
前陆区
塔里木盆地
origin of natural gas
carbon isotope kinetics
pyrolysis experiment
source rock
gas source
foreland region
Tarim Basin
