SEQUENCE STRATIGRAPHIC ANALYSIS ON UPPER PERMIAN HESHAN FORMATION IN HESHAN AND LAIBIN AREAS IN CENTRAL GUANGXI

The present paper analyzes the upper Permian Heshan Formation from Heshan and Laibin areas incentral Guangxi by employing the study methods of outcrop sequence stratigraphy.In the Heshan Formation,7 sequence boundaries and 6 sequences defined by the boundaries are recognized.Among the 6 sequences,5 are attributed to type Ⅰ,and I to type Ⅱ.The sequences were formed in passive continentalmargin environment.Platform area was dominated by the sedimentation of the shallow carbonate sediments,and in the basin area the sediment of deep silicalite was developed in under-compensated conditions.