欧亚北极地区西部区域地质与构造演化

REGIONAL GEOLOGY AND TECTONIC EVOLUTION OF THE WESTERN EUROASIAN ARCTIC

欧亚北极地区西部,西起北大西洋东岸,东至上扬斯克山脉,区域地质构造复杂。根据其构造特征,以乌拉尔-新地岛-泰梅尔造山带为界,可以分为东西两区。西区主要构造单元包括前寒武纪的波罗的克拉通与斯瓦尔巴微板块以及蒂曼造山带、加里东造山带和乌拉尔-新地岛造山带等,而东区主要包括西伯利亚克拉通及上扬斯克造山带。本区主要经历4次大的构造事件:(1)新元古代至早寒武世的蒂曼造山运动,使得波罗的古陆与斯瓦尔巴-喀拉微板块碰撞造山,形成蒂曼造山带;(2)早古生代,奥陶纪-志留纪的加里东造山运动,使波罗的与劳伦碰撞造山,形成加里东造山带;(3)晚古生代,哈萨克斯坦板块与波罗的古陆与西伯利亚古陆的碰撞,形成乌拉尔-新地岛-泰梅尔造山带;(4)早白垩世,科雷马-奥莫隆复合超地体及阿拉斯加-楚科塔微板块与西伯利亚大陆边缘碰撞拼贴,形成上扬斯克造山带和南阿纽伊缝合线。

The western Euroasian Arctic area is located in the large area from the east coast of the North Atlantic in the west to Verkhoyansk Mountains in the east.It is quite complicated in geology.According to the basic geological features,it could be divided to two provinces,say western province and eastern province.In the western province,there are various tectonic units,such as the Precambrian Baltica craton,Siberian craton and Svalbard microplate surrounded by the Timanian,Caledonian and Uralian Orogens,while in the eastern area there occur the Siberian craton and Early Cretaceous Verkhoyansk Orogen.It has experimented four major tectonic events：1）the Timanian orogeny by the latest Neoproterozoic to earliest Cambrian resulted in the collision between Svalbard-Kara microplate and Baltic,and the Timanide was formed;2）the Caledonian orogeny from Ordovician to Silurian resulted in the Baltic colliding with Siberia,and formed the Caledonite.3）The collision of Siberia with Kazakhstan and Baltic in late Palaeozoic resulted in the Ural-Novaya Zemlya-Taimy Orogen.4）The collision of the Kolyma-Omolon Composite Superterrane and Alaska-Chukota microplate with the continental magin of Siberia,resulted in the formation of the Verkhoyansk Orogen and South Anyui Suture.