Abstract: The major oil layers developing in Chunfeng oilfield are located near the unconformity between Shawan formation and Lower Cretaceous (N₁s-K₁), which membership is still disputed nowadays, thus influencing related exploration deployments and development designs for available different horizons. The comprehensive analyses of them are conducted by means of fine stratigraphic correlation, seismic horizon calibration, velocity analysis, attribute extraction and stratigraphic isotopic dating, etc. and it is shown that the major oil layers are of more similarity with the Cretaceous, and they should be reasonably classified into Lianmuqin formation (K1l) of the Lower Cretaceous.

Key words: Junggar basin, Chenfeng oilfield, oil layer, stratigraphic correlation and classification, Lianmuqin formation