中央造山带的演化及其特点

中央造山带原型是由一列微板块加上分别位于其北面和同面的两列不同时期的小洋盆组成，微板块群的主体是柴达木，秦岭，大别－苏鲁，还加上祁连，元古代末至早古生代早期，北列拉张成多岛小洋盆，它们在加里东档期关闭，并在微板块群北缘形成前陆盆地带，南列形成裂陷槽，在加里东期末关闭，一般不造山，晚古生代，微板块群与欧亚板块合为一体，并总体北移，南列出现泥盆（个别）石炭二叠纪的小洋盆，属于古特提斯洋的一部分，洋盆在

EVOLUTION AND CHARACTERISTICS OF THE CENTRAL OROGENIC BELT

The Central Orogenic Belt originally consisted of a series of microplates plus two rows of micro_oceans of different stages located respectively to the south and north of the microplates. Qaidam, Qinling, Dabie-Sulu (Jiangsu-Shangdong) plus central Qilian constitute the main body of the microplates. During end_Proterozoic and early Early Paleozoic, the northern row extended into archipelagic oceans, which closed by the end of Caledonian stage and formed foreland basins along the northern margin of the microplates. Meanwhile the southern row formed rift valleys which closed simultaneously but did not transform into mountains. The microplates incorporated with Eurasia in Late Paleozoic and shifted northward with it. The southern row developed into Late Devonian (individually), Carboniferous-Permian micro_oceans belonging to parts of Paleo_Tethys. They closed during Middle-Late Permian and formed Early-Middle Triassic foreland deposits to their south. During the Indosinian stage this belt belonged to the northern branch of Paleo_Tethys, and the Triassic consisted of three types. The Yanshanian intracratonic compression strengthened eastward, causing maximum subduction and topographic uplift of the eastern microplates. Such effects decreased westwards. Plate tectonics of the Central Orogenic Belt ensues mainly the Non_Wilson Cycle rather than the Wilson Cycle. The Non_Wilson Cycle differs from the Wilson Cycle in three aspects, i.e., archipelagic ocean, soft collision and multicyclicity. This paper discusses their characteristics, and emphasizes that the Non_Wilson Cycle with its three aspects is of general significance in the development of Paleo_Asian and Tethys Oceans which occupied the main territory of China in geological history.