ONE COAL BEARING LOW ENERGY BARRIER LAGOON DEPOSITIONAL SYSTEM——TAKING UPPER COAL MEASURES IN LATE PERMIAN IN ZHIJING AREA,GUIZHOR PROVINCE AS AN EXAMPLE

The Zhijing area is located in the northeast margin of the Late Permian terrigenous clastic deposits in western Guizhou province.The Late Permian coal-bearing deposits in the area are the Longtan-type of one and belong to the barrier-lagoon system.The section with coal No.2 of the upper coal measures in the area discussed in the paper represents a kind of low energy and small scale barrier-lagoon system,which is composed of tide flat,freshening lagoon,peat-swamp and low energy barrier facies and is suggested to be called as coal-bearing low energy barrier-lagoon depositional system