The Research Of Reservior Fiuld Geochemical Description In Tahe Oilfield

Petroleum reservoir geochemistry is a new frontier and has become one of the important research field in petroleum geology since the late 1980s.It is based on the key technology of the thin layer chromatography flame ionization detection (TLC-FID) and the oil show analyzer (OSA).The result of reservoir geochemical description is not depended the fluid character and composing, so it can complement the shortage of well logs and mud logs. It is equal to the Tahe oilfield where there is complex petroleum.Based on a systematic analysis of a lot of core and oil from Tahe Oilfield, applying for the theory and technology of reservoir geochemical description, the paper show content of hydrocarbon rate of reservoir, communication and distribution characteristics together with regional geology and latest research date forming machine and control factors were studied combining with hydrocarbon migration and accumulation.According to the Ordovician core form 18 wells on Tahe oilfield geochemical analysis, it was considered that hydrocarbon prospects of reservoir in middle-lower Ordovician are higher than upper Ordovician. The types of petroleum property analysis shows that there is heavy oil in zone 4 and zone 6,middle oil in zone 2and zone3,and light oil in zone 9,mixing oil in zone 7 in Tahe Oilfield. It is two basic factors to from the tar mats that high content of asphalt and content rate of oil. There are many tar mats in middle-lower Ordovician. It is disadvantage for developing, but sometime it is advantage for sealing. In upper Ordovician, there are a few of tar mats because of its lower content of oil rate.The physical properties and biomarker of petroleum represents the direction of hydrocarbon migration was from south to north in the early and it migrated both form south to north and form east to west in the late. On basis of studies of reservoir bitumen, liquid inclusion, the main stages of formation of hydrocarbon pools in Tahe Oilfield is late Hercynian.Combining all feather, hydrocarbon distribution in space resulted in the direction of migration, multiple pool-forming and secondary alterations and maxing of proportion of petroleum in different period. But the core factors which caused the complexion distribution of petroleum property were multiple pool-forming and proportion of petroleum in different accumulation period.All these result of research will provide useful information for exploration and development of the Tahe oilfield in the future.