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大别造山带、东秦岭造山带和东昆仑造山带是中国中央山系的主要构成部分,每个造山带古老岩系的变质作用过程各具特色.大别山最古老岩系大别岩群于印支期陆内俯冲碰撞,发生了区域性的中偏高压区域变质作用,顺时针型pt轨迹上tmax和pmax近于同时达到,退变质轨迹段斜率陡,埋深后受构造驱动快速抬升到上中地壳.东秦岭最古老岩系秦岭岩群在晋宁期(约1.0Ga前)初始板块构造总背景下发生强烈的中压型碰撞变质作用,顺时针型pt轨迹上tmax在压力大幅度降低的过程中达到,反映弧陆碰撞增厚后深埋岩系受重力均衡抬升;至加里东期,秦岭岩群再次在板块构造的总背景下发生岛弧型变质,局部叠加中压型接触变质作用;晚海西以来北秦岭东段缺乏高于低角闪岩相条件的区域变质作用记录.东昆仑造山带最古老岩系于吕梁或早吕梁期发生中压碰撞区域变质,主体为角闪岩相,局部高角闪岩相-麻粒岩相条件,造山带剥露较浅使低压变质带得以良好保存.
The Dabie orogenic belt, the East Qinling orogenic belt and the East Kunlun orogenic belt are the major components of the central mountain system in China. Each metamorphic process of the ancient rock series in the orogenic belt has its own characteristics. During the Indosinian intraconducto-subduction collision, the Dabie Group, the oldest member of the Dabie Mountains, experienced regional metamorphism in the middle-high-pressure region. The tmax and pmax of the clockwise pt trajectory were nearly at the same time, and the slope of the retrogressive mass trajectory was steep , Buried deep and driven by tectonic uplift to the upper crust. The Qinling Group, the oldest member of the East Qinling, experienced a strong mid-pressure collision metamorphism under the general background of the initial plate tectonics in the Jinning Period (about 1.0Ga ago). The process of tmax on the clockwise pt trajectory was greatly reduced , Which indicates that the deep-buried rock series are uplifted by gravity balance after the arc-continent collision thickened. By the Caledonian period, the Qinling Group again occurred island arc metamorphism and partial superimposition of medium-pressure contact metamorphism under the general background of plate tectonics. Since the Late Hercynian, there was no record of regional metamorphism over the Lower Amphibolite facies. The eastern Kunlun orogenic belt in the Lüliang or early Luliang period occurred in the mid-pressure collision area metamorphism, the main body of the amphibolite facies, local amphibolite facies-granulite facies facies, shallow orogeny exposed shallow low-pressure metamorphic belt Well preserved.