【摘要】 塔里木盆地早奥陶世晚期进入伸展转向挤压的区域构造背景,造成台缘带挠曲下沉与台内地貌起伏,有利中下奥陶统鹰山组台内滩的发育。钻井资料表明鹰山组台内滩以中高能砂屑滩为主,台内滩主要分布在鹰山组上部,纵向上多旋回叠置,横向呈透镜状尖灭。通过井—震标定,鹰山组台内滩在地震响应上多具有平缓顶底面的丘状外部形态,内部多出现高频杂乱反射,有的出现多层斜交或前积反射,翼部围岩具有超覆与斜交反射,具有不同于围岩的强振幅特征。结合地震响应特征,利用地层厚度、地震属性等作图方法,可以进行台内滩的预测与识别。地震区域追踪判识表明,塔里木盆地中西部鹰山组台内滩发育,多呈团块状形态,大小不一,一般规模在100～300 km2,发育总面积达12 000 km2,集中分布区有塔北南缘、塔中北斜坡、和田河气田及其周缘等三大区块,并多沿古隆起斜坡分布。塔里木盆地台内滩类型多、分布广,是下古生界碳酸盐岩从台缘带向台内扩展的值得深入研究的有利探索领域。更多还原

【Abstract】 Based on the analysis of regional geology,and the discontinuity of stratum and lithology,the change of sedimentary facies,and the development of palaeo-uplifts,the transform stage of the regional deposition-tectonics cycles changed from extension to compression began at the end of the early Ordovician in Tarim basin.The early-middle Ordovician Yingshan Formation platform margin began bending and downwelling which caused the deepening upward depositional cycles with middle-low energy reef-bank complex along the margin.And it is favorable for the intra-platform beach development of Yingshan Formation in the western platform in Tarim basin,when the intra-platform ascending with morphologic prominence and lacking of platform margin barriers.Based on the well data,medium-high energy arene beaches are well developed with some of grit and oolitic beaches in intra-platform in Yingshan Formation,with 3~8 layers of multi-cycles deposition aggraded vertically,and lenticular or sheet-like pinchout and changed quickly laterally.The seismic response of intra-platform beaches of Yingshan Formation is different from the adjacent formation by well-seismic calibration.It displayed various mound and lenticular external shapes with lightly upper convex of the cap face and relatively even basal plane.The seismic wave of the most intra-platform beaches can be distinguished from the adjacent formation with weak reflection or chaotic reflection of top surface,but with discontinuous and strong reflection in case of thick mudstone cap formation,and with weak amplitude,discontinuous minor axis shape or chaotic reflection or disconnection strong wave.There are overlap and oblique reflection on the flank and thinning phenomenon of the overburden layer in the seismic section.The internal of most beaches have high frequency chaotic reflection,abnormaly strong and weak amplitude alternation,and some of them have multilayer crossing or progradation reflection which indicated multicycle beaches aggradation.On the basis of the characteristics of seismic facies,the formation thickness and seismic attributions,prediction and identification of Yingshan Formation intra-platform can be carried out in the western Tarim basin.By the regional seismic tracing and identification,there developed many large areas of intra-platform beaches in Yingshan Formation with blocklike shape horizontally and different size,most of the scales between 100 km2 and 300 km2,and the total area up to 12 000 km2.The intra-platform beaches mainly distributed in the southern slope of Tabei uplift,the northern slope of Tazhong uplift and the periphery of Hetihe gas field,most of which distributed along the slope of paleo-uplift.The Ordovician Yingshan Formation intra-platform beach,had better reservoirs with many types and wide distribution and great superimposd thickness,is favorable research aspect of potential exploration region of carbonate after the platform margin reef-bank field found in Tarim basin.And more important discovery can be obtained in intra-platform beaches along the favorable accumulation slopes of palaeo-uplift by means of reservoirs seismic prediction to choose pay targets.更多还原