EVOLUTIONARY CHARACTERISTICS OF THE CARBONIFEROUS SEDIMENTATION AND DIAGENESIS CONTROLLED BY THE SEQUENCE STRATIGRAPHIC FRAMEWORK OF THE WEST TARIM BASIN

According to the ordered superimposed styles of high frequency cyclic sequences within long period cyclic sequences,three Ⅲ order cyclic sequences and two Ⅱ order cyclic sequenes were divided in the Carboniferous of the study area.Among them,Ⅲ 1 and Ⅲ 3 cyclic sequences belong to the transgressive tract system,and Ⅲ 2 belongs to the highstand tract system.They constitute together the sequence stratigraphic framework of the study area and control the space time distributive characteristics of sedimentary facies and source rock reservoir cap rock assemblages.As affected by the differences of diagenetic history and different diagenetic environments,the diagenetic characteristics and storage peformances of the Carboniferous clastic and carbonate reservoir rocks have obvious differences between the Bachu Uplifting area and the Maigaiti Slope area.Besides,the reservoirs distributing in the slope area have obviously better physical properties than those in the same formations of the uplifting area,and are the favorable exploration targets in the near future.