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大别山北部的北淮阳构造带主体由佛子岭群和庐镇关群构成.北淮阳构造带没有经历超高压变质作用,但却具有与大别山其他地区相同的构造变形形式.通过几何学、运动学及多期构造变形的研究,论证了北淮阳构造带具有与其他地质单元相同的动力学背景.同大别山中部穹隆及南部超高压变质地体相比,由于北淮阳构造带的俯冲深度较浅,从而保留了超高压变质作用之前的构造变形形迹.结合同位素年代学的测量结果,把北淮阳构造带的岩石变形划分为五期,分别代表了早期板块会聚的变形痕迹(D1),早期的构造折返(D2),表示主变形期的晚三叠世的伸展作用(D3),晚三叠世的重力滑脱伸展作用(D4)和白垩纪的伸展作用(D5).结合大别山的岩石变形,可以认为华南与华北板块碰撞造山过程大致经历了陆壳俯冲阶段,同俯冲期的折返作用,穹窿及其边缘的重力滑脱变形和混合岩化及岩浆侵入作用.
The northern Huaiyang tectonic belt in the northern part of the Dabie Mountains consists of the Foziling Group and the Guanqun of Lu Town.The Northern Huaiyang tectonic belt did not undergo the UHP metamorphism but has the same structural deformation as the other parts of the Dabie Mountains.By means of geometry, Kinematics and multi-stage tectonic deformation, it is demonstrated that the Beihuaiyang tectonic belt has the same dynamic background as other geological units.Comparing with the northern Dabie Mountains and the UHP metamorphic terranes, due to the subduction of the Northern Huaiyang tectonic belt And the depth is shallower, so as to preserve the structural deformation before the UHP metamorphism.Combined with the results of isotope chronology, the rock deformation of the Northern Huaiyang tectonic belt is divided into five phases, representing the deformation traces of the early plate convergence (D1 ), Early tectonic reentry (D2), Late Triassic extension of the main deformation period (D3), Late Triassic gravitational slip extension (D4) and Cretaceous extension (D5) Of the rock deformation, we can think that the collision between the South China and North China plate orogenic processes generally experienced the continental crust subduction stage, with the subduction of the reentry role, the dome and its edge of the gravitational slippage deformation and mixed rock And magma intrusion.