Abstract:

On the basis of the larger regional unconformity,Changling depression can be divided into 2 second-order sequences of Quantou Formation-Qingshankou Formation and Yaojia Formation-Nenjiang Formation.Marked by the local unconformity and sedimentary transformation base,Qingshankou Formation can be subdivided into 4 third-order sequences.In Daqingzijin region situated in front of the deltaic sandstone body of Baokang,sandstone bodies are widely spread in sequence S1 and S2 of lowstand system tracts which are main oil-bearing strata in that region.Sequence stratigraphy does not only control the type of oil and gas accumulation but also control the nature of oil bearing.60% of industrial oil and gas wells are estimated to locate in the low level system tracts.

Key words: sequence stratigraphy, dividing, reservoirs, Changling depression