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西藏羌塘盆地中生代构造岩相组合分带及特征明显 ,可以反映羌塘盆地的演化史。早中三叠世北羌塘构造岩相组合表现为前陆盆地沉积 ,而南羌塘盆地为剥蚀环境 ;至晚三叠世除中央隆起剥蚀外 ,北羌塘仍为前陆盆地沉积 ,而此时南羌塘坳陷演化成陆缘海沉积。早侏罗世早期盆地开始坳陷 ,造成相对较窄沉积相的构造岩相组合特点 ,初步形成“两坳一隆”的构造格局 ;中侏罗世南北羌塘坳陷继续下降 ,“两坳一隆”的构造格局更加明显 ;晚侏罗世羌塘盆地发育到晚期 ,并萎缩、封闭成型。从构造岩相组合特征看 ,中侏罗统北羌塘坳陷龙尾湖—雀莫错凹陷区与南羌塘坳陷蒂让碧错凹陷区都是有利于储、聚油气的远景区。
The combined zonation and characteristics of the Mesozoic tectonic lithofacies in the Qiangtang Basin in Tibet are obvious, which can reflect the evolutionary history of the Qiangtang basin. The Early Triassic North Qiangtang lithofacies assemblages are characterized by foreland basin sedimentation, while the southern Qiangtang basin is denudation environment. In the Late Triassic, except for central uplift and denudation, the northern Qiangtang is still foreland basin sedimentary whereas At this time, the South Qiangtang depression evolved into continental margin deposition. Early Early Jurassic basin began to depress, resulting in relatively narrow sedimentary facies lithofacies assemblage characteristics of the initial formation of “two Au a Long” structure; Middle and Late Jurassic Qiangtang depression continued to decline, “two Au A Long ”structure more pronounced; Late Jurassic Qiangtang basin developed to late, and shrink, closed molding. From the characteristics of tectonic facies assemblages, the Longtiao-Catola Sag in the Middle Qiangtang depression of Middle Jurassic and the Dijikapo depression in the South Qiangtang depression are all favorable prospects for reservoir and poly-oil gas.