Abstract: The research of outcrop,drilling, well log and seismic data showed that in J₁s₂² sand body of Jurassic Sangonghe formation in Junggar basin, a Jurassic interior sequence interface that defined as J₁S₃ was developed on anti-cycle’s turning point, with obvious recognition mark and fair responses in outcrop, drilling, well log and seismic profile. Because of bigger differences of assemblage relations of J₁s₂² sand body in different parts of the basin,extreme differences occurred in the interfacial configuration,mainly showing the characteristics of complicated contact relations between upper and lower lithologic properties in bottom of the sequence, varied geophysical parameters along its strata as well as bigger differences in upper and lower seismic interface reflection structures. The important controlled factor of forming non-homogeneity of this interface within the whole basin could be the fact that differentials of structural movement, particularly, those of local structural movements in the whole basin, which lead to variation of containable spaces in the different areas. Also, deposit supply and climatic variation or fluctuation is one of primary affective factors.

Key words: Junggar basin, Early Jurassic, sequence stratigraphy, interface