塔里木盆地下古生界碳酸盐岩台缘结构特征及其演化

台缘斜坡带以发育灰泥丘烃源岩和礁滩相储层备受关注，而台地结构样式制约着台缘斜坡带的发育类型和空间展布格局。在地震、测井、岩心、露头等资料的综合分析基础上，研究发现塔里木盆地下古生界发育缓坡型、镶边型、孤立型和淹没型4种碳酸盐岩台地结构样式。同一时期的不同地区台地结构样式存在差异:寒武纪时期,塔中、塔北为进积缓坡型碳酸盐岩台地，而塔西南为退积缓斜坡型碳酸盐岩台地；早奥陶世时期,塔北为退积镶边型碳酸盐岩台地，而塔中、塔西南地区则为加积镶边型碳酸盐岩台地。台地结构在纵向上发育演化的同时，台缘坡折带在平面上也发生迁移变化：寒武纪时期台缘坡折带环绕着西部台地呈向西开口的“U”字型分布；早中奥陶世塔西南地区的台缘斜坡带向盆内迁移，塔中、塘南地区分别发育中古台槽和塘南台缘坡折带；晚奥陶世时期塔里木盆地整体呈现“3个半岛型台地”、“4个台地边缘相带”的沉积格局。塔西南地区寒武-奥陶纪的台缘坡折带、塔中地区早、中奥陶世的中古台槽以及塘南地区奥陶纪台缘斜坡带的发现，对塔里木盆地早古生代沉积格局的重新认识具有重要意义。

Structure Characteristics and Evolution of the Eopaleozoic Carbonate Platform in Tarim Basin

The platform slope is concerned because the lime-mud mound source and bank-reef facies reservoir are developed there and its development is controlled by the platform structure style.Basing on the comprehensive research of seismic,logging,core,and outcrop data,it is proposed that four types of carbonate platformis developed in Cambrian-Ordovician in Tarim basin,i.e.ramp carbonate platform,rimmed shelf carbonate platform,isolated carbonate platform and drowned carbonate platform.The structure style of carbonate platform has distinct diversities in different areas in the same phase and the slope distribution has migrated in different phases.The prograded ramp carbonate platform is developed in Cambrian in the central and northern Tarim basin,while the retrogradated wide gentle slope occurs in Cambrian in the southwestern Tarim basin.The retrogradated rimmed shelf carbonate platform is developed in Early Ordovician in the northern Tarim basin,while the aggraded rimmed shelf carbonate platform occurs in Early Ordovician in the southwestern and central Tarim basin.The platform slope is formed in Cambrian,distributes around the west platform,represents U shape toward west,and the platform slope is formed in Early-Middle Ordovician migrates toward platform.The integrity attributes of the slope in Later Ordovician is that the three platform slopes distribute around four islands.The existences of the platform slope of the southwestern and central Tarim basin and Tangnan area play an important role inreservoirevaluation and source predication in Tarim basin.