PERMIAN AND TRIASSIC SEQUENCE STRATIGRAPHY FRAMEWORK OF THE DINAN UPLIFT IN JUNGGAR BASIN

Based on the characters of seismic reflections and the analysis of geologic setting in the Dinan uplift in Junggar basin, three boundaries of sequence are recognized, i.e. the bottom of Permian, the top of Triassic and the boundary between Permian and Triassic. These boundaries are unexceptionally regional surfaces of abrupt change of lithology and well logging. Enlightened by this recognition, the boundary between Karamay and Baijiantan formations is analyzed. The result shows that this regional lithologic face also behaves as stratum absent face and strong seismic phase axis. Therefore it is a sequence boundary. Totally three sequences with seven system tracts are divided for the Permian and Triassic strata in the Dinan uplift.