储层岩石中稀有气体组分和同位素分析技术  

Measurement technology for content and isotopic compositions of noble gases in reservoir rocks

作　　者：杨华敏[1,2] 王杰[1,2] 陶成[1,2] 刘文汇[1,2] 

机构地区：[1]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214151 [2]中国石化油气成藏重点实验室,江苏无锡214151

出　　处：《天然气地球科学》2016年第4期681-687,共7页Natural Gas Geoscience

基　　金：国家重点基础研究发展规划("973")项目(编号:2012CB214801);中国石化股份有限公司科技部攻关项目(编号:P12009)联合资助

摘　　要：利用自制真空球磨脱气装置,与稀有气体纯化富集系统,四极杆质谱计及稀有气体同位素质谱计联机使用,可对储层岩石样品进行脱气、纯化富集等前处理,并完成稀有气体全组分氦、氖、氩、氪、氙的含量和各个同位素比值分析。空白实验测试了各个系统的动态真空压强、静态漏率均满足实验要求。当真空球磨脱气罐空转运行10min,本底空白值为1.0×10^(-1) Pa,40 Ar离子流强度在1.3×10^(-10 )A量级,不会对样品气造成影响。测试了塔河油田奥陶系钻井岩心样品的稀有气体组分和同位素值,并与同区块天然气样品的稀有气体氦、氩数据做对比。结果表明岩石样品中稀有气体氦、氩数据与同区块的天然气氦、氩数据指标具有可比性,岩样的稀有气体数据也可应用于成藏定年,即岩样中~3 He/~4 He同位素特征可用来划分区域构造的相对活动性,^(40)Ar/^(36) Ar值是估算气源岩时代的有效指标,可用来计算成藏年代。因此当缺乏天然气样品时,一定程度上也可用储层岩石代替气样做稀有气体同位素分析。With connecting self-designed Vacuum-Ball mill device,noble gas purification and concentrating system,Quadrupole Mass Spectrometer and noble gas isotope mass spectrometer,we can extract,purify,concentrate gases from reservoir rocks.And the content and isotopic compositions of total noble gases in reservoir rocks are successfully measured.In blank test,the dynamic vacuum pressure and static rate of leak all meet the demands.When the self-designed Vacuum-Ball mill device runs for 10 mins,the background＇s pressure is 1.0×10^-1Pa,the intensity of mass ^40Ar is 1.3×10^-10 A,sample gases are not affected.The contents and isotopic compositions of total noble gases were measured from Ordovician rocks of drilling cores in Tahe Oilfield,compared with He,Ar contents and isotopic compositions from the same area＇s natural gases.The results show perfect compatibility of the contents and isotopic compositions of He,Ar between reservoir rocks and natural gases.Noble gases indicator can also be used for accumulation dating.Relative activity for regional structure is divided by ^3 He/^4 He in reservoir rocks,and ^40 Ar/^36 Ar is effective indicator for estimating gas-source rock time.So for the interval with absence of natural gas samples,it can be replaced by reservoir rocks accordingly.

关 键 词：稀有气体组分和同位素 分析技术 储层岩石 成藏定年 

分 类 号：TE122.2[石油与天然气工程—油气勘探]