应用流体包裹体厘定合兴场地区须家河组天然气成藏期次

Using fluid inclusion to redefine gas accumulation stages of Xujiahe Formation in Hexingchang area

通过对合兴场地区须家河组四段和二段中230个包裹体样品的分析,根据油气包裹体及含烃盐水包裹体特征,结合地层埋藏史,确定了气藏的成藏年代。气藏油气充注过程为:须四段(3385.4m)均一化温度的主峰分别为77～98℃和118～120℃,对应成藏期为中侏罗世中晚期和晚侏罗世中期,前者为主要成藏期;须二段(4612.77m,4562.7m)均一化温度的主峰分别为95～106.1℃,119.8～127.1℃和134.5～140.1℃,对应的主成藏期为晚三叠世末期到早侏罗世早期和中侏罗世晚期。

Based on the analysis of 230 inclusion samples of the second and fourth members of Xujiahe Formation in Hexingchang area,the characteristics of hydrocarbon inclusion and hydrocarbon-bearing salt water inclusion combining with burial history are used to define the gas reservoir formation time.The process of hydrocarbon accumu-lation in the study area is as following：The two main peak homogenization temperatures of the fourth member of Xujiahe Formation ranges from 77 ℃ to 98 ℃ and from 118 ℃ to 120 ℃ respectively,and the corresponding hydrocarbon accumu-lation stages are middle-late stage of Middle Jurassic and middle stage of Late Jurassic,with the former as the main accumulation stage;The main peak homogenization temperatures of the second member of Xujiahe Formation ranges from 95 ℃ to 106.1 ℃,from 119.8 ℃ to 127.1 ℃ and from 134.5℃ to 140.1 ℃ respectively,and the corresponding hydrocarbon accumulation stages are from the late stage of Late Triassic to the early stage of Early Jurassic and late stage of Middle Jurassic.