【摘要】 塔里木盆地西南缘的石炭系由海相碎屑岩和碳酸盐岩组成,厚逾2000m。根据岩石相,区内石炭系自下而上可分出3个纵向相组合:①泻湖白云岩和浅滩鲕粒灰岩;②陆棚页岩、灰岩和滨浅海砂、砾岩;③台地灰岩。在本区的西北部,这些组合逐渐过渡为深水碎屑岩和灰岩;在本区的东部,组合①和②缺失,组合③变薄。上述沉积组合分别形成于半局限海湾、三角洲、碎屑滨岸、混合陆棚和碳酸盐台地环境。沉积特征表明,区内石炭系具有中等生油条件,较差的储集条件和好的盖层条件,次生孔隙是油气潜力的关键。更多还原

【Abstract】 The Carboniferous rocks in the Tiekelike thrust fault belt of southwestern Tarim Basin were deposited in shallow marine and deep basin environments. The most complete sedimentarysequence, more than 2000m in thickness, with the bottom and top of carbonates and the middlepart of interbedded shales, sandstones and limestones, developed in the Shache-Yiechengarea. Consequently, based on the petrofacies, the Carboniferous sediments of the region can be divided, from bottom to top, into three assemblages of sedimentary faciess: 1) lagoonal dolomitesand shoal oolites, 2) shelf shales, limestones and clasts and 3) shelf-platform limestones. Toward the northwest of the study area these assemblages gradually turn to deep-water elasticdeposits. East of the region the assemblages 1) and 2) are mostly absent and 3) gently getsthinner. These facies assemblages are considered to the products of the sedimentations of semi-restricted bay, braid delta, clastic shoreline, mixed elastic and carbonate shelf, carbonate platform, andturbidity basin. According to the siderite nodules in the main source rocks, the marine shales and thecementation of silicon in the main reservior rocks, the marine sandstones, the deposit environmentsare somewhat rich in oxygen and the diagenesis is strong. The relatively lower content of organiccarbon (0.5% on the average) of the shelf shales presents a middle ability of middle-scalehydrocarbon generation. The cements of the sandstones indicate that the reservior porosity is mainlycontroled by the burial diagenesis.更多还原