ANALYSIS ON SEQUENCE STRATIGRAPHY AND DEPOSITIONAL SYSTEMS OF THE CARBONIFEROUS IN WEST MANJIAER REGION

Based on the comprehensive using of outcrop,borehole,logging and seismic data and the boundary characteristics of depositional system tracts,the Carboniferous of West Majiaer area,Tarim Basin were divided into six sedimentary sequences.And development of the lowstand,trangressive and highstand system tracts was ascertained.The study area was located on the continental shelf during Carboniferous.The major depositional systems were composed of 1) river system;2) littoral system;3) shallow marine shelf system;4) shallow carbonate system;5) fan-deltaic system;6) coastal plain system;7) lagoon system;and 8) mixed clastic-carbonate system.Lowstand system tracts were characterized by river system;and shallow marine shelf,shallow carbonate platform,coastal plain and mixed clastic-carbonate systems were developed in trangressive system tracts.Except for river system,all other systems were developed in highstand system tracts.The reservoirs were mainly developed in the littoral system of highstand system tracts.