Maturity effects on steranes of source rocks in Lishu fault depression,Songliao Basin

作     者：Chuanjun Yi Min Zhang Li Teng Chuanjun Yi;Min Zhang;Li Teng

作者机构：College of Resources and EnvironmentYangtze UniversityWuhanPeople's Republic of China Key Laboratory of Exploration Technology for Oil and Gas ResourceMinistry of EducationWuhanPeople's Republic of China 

出 版 物：《Acta Geochimica》 (地球化学学报（英文）)

年 卷 期：2020年第39卷第4期

页      面：561-573页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：financially supported by the National Natural Science Foundation of China(Grant No.41772124) 

主　　题：Thermal effect Steranes Genetic mechanism Lacustrine source rocks Maturity 

摘      要：Geochemical analysis results of 30 source rock samples from Lishu fault depression in Songliao Basin show that samples are compositionally similar and represent a uniform organic *** distribution of steranes among the samples is due to rank,with vitrinite reflectances(Ro)ranging from 0.65 to 1.61%.In the maturity stage(Ro=0.65-1.20%),the absolute concentrations of steranes increase,which is affected by kerogen degradation,whereas the pyrolysis of high mature source(Ro=1.20-1.61%)show a decrease in the abundance of ***,the parameters of steranes vary greatly with *** of prognane/regular sterane value with the increase of maturity suggests that pregnane is not a product of regular steranes *** ratios of C27/C29regular sterane gradually increase,while the value of C29-20S/(20S+20R)and αββ/(αββ+ααα)decrease at high maturity stage,which is associated with the difference in the thermostability of steranes *** reversed trend can be used to determine the high-maturity stage of source *** the values of rearranged steranes/regular steranes in source rocks show an apparent positive correlation with maturity,it,therefore,appears to be particularly useful for maturity assessment at elevated levels.