摘要
Steranoids and terpanoids in source rocks and crude oils from the Gaoyou depression have been analyzed by GC-MS.The fact that C20 sterane 14 α（H)17α(H)20S/14α（H）17α（H）20（R+S）%and C31 hopane 17α（H）21β（H）22S/17α（H）21β（H）22（R+S）%in the oils are higher than those in the source rocks,as has been revealed in this study,is eonsidered.to have resulted from,oil migration.By comparing steranes and hopanes in inmature oils from the eastern part of China with those in source rocks,it is suggested that the source rocks with over 10% C20 sterane 14α（H）17α（H），20S/14α（H）17α（H）20（R+S）%，over 3% C29 sterane 14β（H）17β（H）20（R+S）[14α（H）17α（H）20（R+S）+14β（H）17β（H）20（R+S）]% and≥50%,C31 hopane 17α（H）21β（H）22S/17α（H）21β（H）22(R+S)%in the eastern part of China may produce crude oils of commercial importance.It seems possible to find inmature oils in the sedimentary rocks at burial depths shallower than the oil-generating threshold and mature oils migrated from deep levels in shallow reservoirs.
Steranoids and terpanoids in source rocks and crude oils from the Gaoyou depres-sion have been analyzed by GC-MS. The fact that C29 sterane 14 α(H)17α(H)20S/14α (H)17α(H)20(R+S)%and C31 hopane 17α(H)21β/17α(H)21β(H)22(R+S)% in the oils are higher than those in the source rocks, as has been revealed in this study, is considered to have resulted from oil migration. By comparing steranes and hopanes in inmature oils from the eastern part of China with those in source rocks, it is suggest-ed that the source rocks with over 10% C29 sterane 14 α(H) 17α(H) 20S/14α(H)17α (H)20(R+S)%, over 3%,C29 sterane 14β(H)17β(H)20 (R+S)/[ 14α(H)l7α(H)20(R + S) + 14β(H)l7β(H)20(R+S)]%and≥50% C31 hopane 17α(H) 21)β (H) 22S/17α (H) 21β (H) 22 (R+S) % in the eastern part of China may produce crude oils of commer-cial importance. It seems possible to find inmature oils in the sedimentary rocks at bu-rial depths shallower than the oil-generating threshold and mature oils migrated from deep levels in shallow reservoirs.
出处
《地球化学》
CAS
1985年第1期80-89,共10页
Geochimica
