In order to determine the extension directions of the sandbodies,with the help of the core calibration imaging logging data,the dip mode maps of the lithological sedimentation beddings were established,the directions of the sandstone cross-bedding after were determined after removing the structural influences,the changes of the sandstone and vertical palaeo-current directions were judged for the individual well,and moreover integrating with the palaeo-current directions,the source directions,the extension of the sedimentary facies and so on,the comprehensive analysis was conducted.The researches show that there are four types of the bedding mainly developed in Shahezi Formation of Anda Sag,the palaeo-current directions in the convergence point to the center of the basin,the deposits are controlled by two big EW-direction sources and their transportations are from the edge to the center,the western fan-delta front and the eastern braided river delta-front facies belt are widely developed,they are regarded as the much better reservoir development areas.The actual drilled results of the horizontal well in the favorable blocks of Shahezi Formation are consistent with the prediction of the sandbody spread directions and furthermore the incremental effects are much more obvious.%为了确定徐家围子断陷安达凹陷沙河子组砂岩体的延伸方向,通过岩心刻度成像测井资料建立岩性沉积层理的倾角模式图,确定去除构造影响后的砂岩交错层理的方位,判别单井的砂体古水流方向和纵向上古水流方向变化,再结合区域的古水流向、物源方向、沉积相带展布等进行综合分析.研究认为:安达凹陷沙河子组主要发育4种层理类型,古水流方向呈内收敛状指向盆地中心,沉积物受东西两大物源控制,从盆地边部向中心搬运,西部扇三角洲前缘及东部辫状河三角洲前缘相带广泛发育,为好储层发育区.沙河子组有利区带的水平井实钻结果与砂体延伸方向预测一致,增产效果明显.
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