收稿日期: 2009-07-20
修回日期: 2009-10-15
网络出版日期: 2010-02-10
基金资助
石油化工联合基金(编号:40739902);国家“973”项目(编号:2005CB422102)联合资助.
40Ar Dating Model of Gas Source Rocks and the Quantitative Identification of Mixture Ratios for Duality Sourced Gases in Gas Reservoirs
Received date: 2009-07-20
Revised date: 2009-10-15
Online published: 2010-02-10
对2种不同成因气或同源不同成熟阶段气的模拟实验表明:煤型气、油型气混源气随油型气比例降低,碳同位素组成逐渐变重,氢同位素组成变轻,各组分同位素分馏模式不同,具有三阶段变化模式;同源不同成熟阶段混源气随高熟气比例的增加,烷烃气碳同位素组成逐渐变重\.建立了煤型气、油型气混源比例定量判识的地球化学模板,在雅克拉气田得到了很好地应用\.雅克拉气田主要为油型气,掺混煤型气比例约为12%~20%。同时,建立了同源不同成熟阶段气混源比例定量判识的地球化学模板,在塔河油田应用效果很好。塔河油田天然气由高成熟气与低成熟气混合形成,塔河东部主要以高成熟天然气为主,西部以低成熟气为主,只是混合的比例不同,低成熟气与高成熟气的混源比例在1∶19~13.3∶1之间,天然气由东南向西北、由东向西运移充注。针对南方海相地层实际情况,对氩同位素积累效应确定气源岩时代模型进行了修正,并对大湾2井天然气来源进行了定量判识。
王杰, 刘文汇, 陶成, 秦建中, 腾格尔 . 天然气藏二元混源比例定量判识探讨及气源岩40Ar年龄模型[J]. 天然气地球科学, 2010 , 21(1) : 125 -131 . DOI: 10.11764/j.issn.1672-1926.2010.01.125
Experiments on the mixture of two type gases or different stage gases indicate that the mixture alkane gases have the isotopically heavier carbon and lighter hydrogen with the decrease of oil-type gas mixture, and the three-stage model of stable isotope fractionation occurs. The geochemical pattern of the quantitative identification of the mixing of coal- and oil-type gases was established, and this pattern was successfully used in the Yakela gas pool, suggesting that the gas would be main oil-type gas, and mixed by 12%~20% coal-type gas. In the mixing simulation of different mature gases from the same source rocks, the carbon isotope compositions of alkane gases gradually become heavier with increase of high mature gas mixing. Then we established the geochemical pattern of the quantitative identification of the mixing of oil-type gases at different thermal stages. This pattern was used in the Tahe oilfield and indicated that the mixing of natural gases at high- and low-mature stages existed in the Tahe oilfield, with main high mature gas in the eastern part of Tahe area and low mature gas in the western part. The mixed proportion of low-and high-mature gases in the eastern and western parts ranged from 1 to 19 and 13.3 to 1, respectively. The filling direction of natural gas in the Tahe oil field was from southeastern to northwestern, and eastern to western. According to marine strata feature of south China, the amended dating model of the gas source rock was setup by argon isotope accumulation effect and used to quantitatively identify the gas source in the well Dawan 2 of the northeastern Sichuan basin.
/
〈 |
|
〉 |