【摘要】 早石炭世末,准噶尔-哈萨克斯坦与西伯利亚板块发生陆-陆碰撞,形成大型双重逆冲推覆构造.推覆构造的原地系统为西伯利亚板块陆缘的晚古生代弧-盆体系,地层为下石炭统及泥盆系.外来系统为西伯利亚板块陆缘内侧的基底变质岩系及其重熔而成的混合岩系,地层为前寒武纪中—深变质岩系与下古生代浅变质岩系.滑动系统从下往上分别是角闪岩相、高绿片岩相及绿片岩相韧性剪切带,一部分构造岩是前海西期变质岩系经韧性变形,或之后又经构造重熔所致,另一部分是前海西期混合花岗岩韧性变形的产物.推覆距离至少为110km.推覆方向为250°±5°.扩展方式是后展式.以上表明,滑动系统、外来系统中的变质岩不属中国阿尔泰造山带的基底岩系,外来系统中的混合花岗岩时代不是海西期,而是加里东期,碰撞期后的隆升剥蚀从南东往北西逐渐减弱.更多还原

【Abstract】 The continental collision between Siberian and Kazakhstan-Junggar in Early Carboniferous shaped the large-scale dual thrust-nappe structures in the Altay orogen, NW China. Here the thrust-nappe systems involve an autochthonous system of Lower Carboniferous and Devonian strata, being the part of late Paleozoic arc-basin system of the continental margin of Siberian Plate, an allochthonous system that is comprised of pre-Cambrian middle to high-grade metamorphic rock series, partly remelted into migmatitic granites and early Paleozoic low-grade metamorphic rock series in the inner side of continental margin of Siberian Plate,as well as a gliding system that consists of ductile shear zones in the upward order of amphibolite facies, high greenschist facies and greenschist facies, in which some tectonites are resulted from ductile deformation of pre-Hercynian metamorphic rock series that partly experienced tectonic remelting afterwards, the other from ductile deformation of pre-Hercynian migmatitic granites.The overthrust proceeded along 250°±5°and extended from foreland to backland with the minimum displacement of at least 110 km.All the facts above demonstrate that the metamorphic rocks in the gliding system and allochthonous system are not the basement rocks of Chinese Altay orogen, and that the times of migmatitic granites in allochthonous system are Caledonian , but not Hercynian inferred before. Uplift denudation after collision gets weaker from SE to NW.更多还原