A STUDY ON THE HETEROGENEITY OF SAND BODY RESERVOIRS IN TRIASSIC BRAIDED DELTA, NORTHERN TARIM BASIN──EXEMPLIFIED BY AKEKULE──DALIYA REGION

The Sand body of Triassic braided delta in northwest Tarim basin is one of the major hosting reservoirs of oil/gas pools in this area,which can be divided into a frontal subfacies and plain subfacies according to their depositional features.Based on the analogy of typical sections in field and detailed analyses of drilling cores,six classes of bounding surface and nine architectural units are identified for the sand body of braided delta in Akekule——Daliya region.Furthermore,in view of the features and scale,the hetero-geneity can be classified into four classes,whieh will control the enrichment of oil/gas to different extents,resulting in a petroliferous difference in the sedimentary reservoir bodies either vertically,laterally or upwards.