It is of great significance for study of the temporal-spatial coupling of hydrocarbon migration and accumulation with trap formation to investigate the timing and chronology of hydrocarbon charging in multi-stages superimposed basins. This study

firstly

employed the analytic methods of crude oil and oil inclusion molecular geochemistry

single fluid inclusion microspectrofluorimetric and thermal maturity assessment

and microthermistry to determine the timing of hydrocarbon charging in the Ordovician strata of Tahe oilfield. The results show that the hydrocarbons in the Ordovician were charged in three periods. Secondly

the indirect dating method of aqueous inclusion and the direct dating method of stable radioactive isotope of Re-Os and K-Ar were used to establish the chronological sequence: the first charging event took place during the Middle to Late Caledonian (463. 2-414. 9 Ma)

the second charging event happened during the Late Hercy-nian (312. 9-268. 8 Ma)

and the third charging event occurred during the Himalaya (22-4. 8 Ma). All the three events occurred in the main Tahe oilfield

but only the first and third events developed in the peripheral areas of Tahe oilfield

such as Aiding

Tuoputai and South Tahe areas. Obviously

a deep understanding of the heterogeneity of hydrocarbon charging events and chronology in Tahe oilfield

which were controlled by differential structure evolution

will be helpful for hydrocarbon exploration in the Ordovician of other structural belts of Tarim Basin.