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通过大量野外观察、分析测试和综合研究,结合覆盖全区1∶25万区域地质调查资料及其他前人工作成果,研究了西昆仑及邻区早-中二叠世构造-岩相古地理特征,并探讨了其形成机制。研究表明:西昆仑及邻区早-中二叠世发育典型的沟弧盆系统,自北向南依次发育塔里木陆块、西昆北弧后裂谷盆地、西昆中岩浆弧、西昆南增生楔、玉龙塔格-巴颜喀拉洋盆及甜水海地块。陆相、海陆过渡相、滨浅海相、半深-深海相均有发育,岩相反映的纵向序列表现为海进-海退的旋回性变化,岩浆活动强烈,构造-古地理环境复杂。早-中二叠世是玉龙塔格-巴颜喀拉洋盆扩张最为剧烈且规模为最大时期,主体处于伸展构造背景。中二叠世晚期强烈的华力西构造运动使古板块间的相对运动加剧,玉龙塔格-巴颜喀拉洋盆大洋岩石圈板块向北强烈俯冲,西昆北弧后裂谷盆地形成。早-中二叠世为研究区地球动力学机制从强烈扩张到强烈汇聚的转折时期,加强其构造-岩相古地理特征的研究对建立该区地层序列、探讨其地质演化历史以及指导找矿工作等均具有重要意义。
Through a large number of field observation, analysis and testing and comprehensive study, combined with 1: 250000 regional geological survey data and other previous work achievements covering the whole area, we studied the tectonic-lithofacies palaeogeographical features of the Early-Middle Permian in the West Kunlun and adjacent areas , And discussed its formation mechanism. The study shows that the typical arc-arc basin system developed in the early-middle Permian of West Kunlun and its adjacent areas developed Tarim block, north-west post-Rift basin, Xikun middle magmatic arc, Xikunan hyperplasia from north to south Wedge, Yulongtag - Bayan Kara Basin and sweet water Haitian. The continental facies, the transitional facies between the land and sea, the coastal facies, the semi-deep sediments and the deep sea facies are all developed. The longitudinal sequences reflected in the facies facies show the cyclic changes of the sea-regressive succession. The magmatic activity is strong and the tectonic-paleogeographic environment is complex. The Early-Middle Permian is the Yulongtag-Bayan Kara basin with the most intense and largest expansion, with the main body in the extensional tectonic setting. The intense mid-Permian Variscan tectonic movement exacerbated the relative movement between the ancient plates. The oceanic lithospheric plate of the Yulongtag-Bayankela Oceanic basin strongly subducted northward and the northern Kunlun arc post-rift basin formed. Early-Middle Permian is a transitional period from strong expansion to intensive convergence of geodynamics mechanism in the study area. It is of great significance to study its tectonic-lithofacies palaeogeographic features. It is of great significance to establish the sequence of stratigraphy in this area, discuss its geological evolution history, Work, etc. are of great significance.