甘蒙北山—东疆天山元古代古陆壳特征及其早古生代地壳类型  

OLD CONTINENTAL CRUST FEATURE OF PRO-TEROZOIC ERA AND CRUST TYPE OF EARLY PALAEOZOIC ERA IN GANSU-MENGGU BEISHAN AREA AND EASTEN XINJIANG TIANSHAN MTS

作　　者：左国朝 冯永忠 刘春燕 李茂松[2] 郭召杰[2] 

机构地区：[1]甘肃省地矿局研究所 [2]北京大学地质系

出　　处：《甘肃地质学报》1992年第1期55-67,共13页Acta Geologica Gansu

基　　金：国家自然科学基金(编号:9487001-1)

摘　　要：本文研究了甘蒙北山及东疆天山早古生代地壳类型,划分为元古代的古陆壳、早古生代洋壳、拉张型过渡壳、汇聚型过渡壳。早古生代沿着库米什—卡瓦布拉克—星星峡—小黄山一线自震旦世晚期由东向西逐渐开裂,于晚寒武世至早奥陶世全面打开,形成库米什—小黄山洋盆。其北侧由塔里木古板块北缘分离出中天山微大陆。且末断裂带斜贯全区,起了控制东西两侧构造发展的转换断层作用。甘蒙北山较东疆天山的地壳类型更为复杂,先后发育有奥陶纪拉张型过渡壳—裂谷带和志留纪汇聚型过渡壳—沟弧盆体系。晚古生代全区构造演化进入开合交替时期,其开时形成拉张过渡壳,早古生代洋区在库鲁克塔格北缘哈孜布拉克塔格地区延续到泥盆—石炭纪。Early Palaeozoic crust types of Gansu-Menggu Beishan area and Eastern Xinjiang Tianshan Mts. have been researched and divided into old continental crust,early Palaeozoic ocean crust,tensile transtion-al crust, convergent transtional crust. At early Palaeozoic, along the line Kumishi-Kawabulake-Xing-xingxia Xiaohuangshan, it splited from east to west since late Sinian Period. The whole open was at late Cambrian to early Ordovician &formed Kumishi- Xiaohuangshan ocean basin. The micro- continent of Middle Tianshan Mts. separated from the north of Tarim old plate on the northern. The Qieme fault zone played a important role in control transform fault of both side east and west tectonic development. The crust types of Gansu-Menggu Beishan are more complicated than Eastern Xinjiang Tianshan' s. There were Ordovician tensile transitional crust-rift zone and Silurian convergent transitional crust-trench-arc-basin system from early to late. During Later Palaeozoic Era, whole area tectonic evolution entered open and closed alternatively period,tensile transtional crust formed at the open period. At Early Palaeozoic, ocean has existed untill Devonian-Carboniferous at the Hazibulaketage region of the northern Kuluke-tage.

关 键 词：元古代 古陆壳 地壳 类型 古生代 

分 类 号：P313.2[天文地球—固体地球物理学]