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奥陶系是塔里木盆地的主要勘探目的层系.恢复奥陶纪的构造沉积环境是研究塔里木地块的构造演化历史和预测奥陶系有利储集相(区)带的重要基础.从周缘大地构造背景、岩相与沉积充填、古地理古气候古生态、构造变形和岩浆活动等出发,将盆地沉积充填和周缘造山带的演化相结合,重建了奥陶纪不同地质时期的原型盆地.在奥陶纪,塔里木地区表现出克拉通内拗陷和克拉通边缘拗陷相复合的盆地性质.中西部克拉通内拗陷主要为台地相沉积区,东部克拉通边缘拗陷主要为深水盆地相区,其间为斜坡过渡带.晚奥陶世,北昆仑洋的闭合和阿尔金地区沟-弧-盆体系的消亡导致塔里木南部地区处于挤压隆升背景,中西部的碳酸盐台地相区转变为混积陆棚,东部的盆地相区出现超补偿的巨厚复理石沉积,标志着盆地性质的急剧转变,盆地格局由奥陶纪的东西分异向志留纪的南北分异转化.
The Ordovician is the main exploration target strata in the Tarim Basin.The restoration of Ordovician tectonic sedimentary environment is an important basis for studying the tectonic evolution history of the Tarim block and predicting the favorable reservoir facies belt of Ordovician.From the peripheral land Tectonic setting, lithofacies and sedimentary filling, palaeogeography and paleoclimatic paleoclimate, tectonic deformation and magmatism, etc., Combining the sedimentary filling of the basin and the evolution of the peripheral orogenic belt to reconstruct the prototype basins in different geological periods of Ordovician. The Ordovician and Tarim areas show the complex basin nature of the craton and the craton marginal depression.The craton in the central and western China is dominated by the platform sedimentary facies and the eastern craton marginal depression is mainly the deep-water basin facies And the transitional zone between them.The transition between the Late Ordovician and the North Kunlun Ocean and the ditch-arc-basin system in the Altyn Tagh area lead to the southern part of the Tarim Basin in the background of compressional uplift and the carbonate platform in the Midwest Transforms into a mixed-type shelf, and the overcompensated gigantic-thick flysch deposits in the eastern basin facies signify a drastic change in the nature of the basin. The pattern of the basin varies from Ordovician to Silurian North-South differentiation.