Closing history of the southern Tianshan oceanic basin, western China: an oblique collisional orogeny
Closing history of the southern Tianshan oceanic basin, western China: an oblique collisional orogeny
复制标题
DOI：
10.1016/s0040-1951(98)00273-x
复制
发表时间：
1999-02-15
期刊：
影响因子：
2.9
通讯作者：
Wu, SM
中科院分区：
文献类型：
--
作者：
Chen, CM;Lu, HF;Wu, SM
天山(天山)山脉是重要的古生代碰撞造山带，是认识中亚构造演化的关键。本文结合已有的国内外天山、塔里木地区沉积学、地球化学、同位素年代学、古隆起学、古地磁等方面的研究成果，提出斜向碰撞作用在南天山洋盆晚古生代闭合中可能起了重要作用。由于震旦纪(晚元古代，小于800 Ma)的大陆伸展和裂谷作用，塔里木和伊犁地块在晚寒武世-奥陶纪从母大陆分离出来。两个地块之间的南天山洋壳向北俯冲到志留纪伊犁地块南缘之下。在泥盆纪-早石炭世，塔里木地块迅速向北漂移，并顺时针旋转约46度。这一过程导致伊犁微大陆在晚泥盆世与塔里木大陆东段(现今地理位置)发生碰撞，南天山洋壳演化为西向残馀洋盆。晚石炭世-早二叠世，塔里木地块位于几乎恒定的纬度范围内，相对于伊犁微大陆顺时针旋转约26度，最终由东向西呈剪刀式闭合残留洋盆，完成了塔里木-伊犁碰撞。在塔里木-伊犁缝合带南缘，塔里木陆壳的A型俯冲和岩石圈规模的左行剪切作用形成了岩浆。晚二叠世-早三叠世沉积于弧以上的周缘前陆盆地的碎屑岩。(C)1999 Elsevier Science B.V.保留所有权利。
The Tianshan (Tien Shan) Range is an important Paleozoic collisional orogenic belt and the key to understand the central Asia tectonic evolution. This paper integrates our research results with the existing Chinese and international literature on sedimentology, geochemistry, isotopic geochronology, paleontonology and paleomagnetism of the Tianshan and Tarim regions to propose that the oblique collision may have played an important role in the late Paleozoic closing of the southern Tianshan oceanic basin. As a result of the Sinian (latest Proterozoic, younger than 800 Ma) continental extension and rifting process, the Tarim and Yili blocks separated from their parent continent in the Late Cambrian-Ordovician. The southern Tianshan oceanic crusts between the two blocks subducted northward beneath the southern margin of the Yili block in the Silurian. During the Devonian-Early Carboniferous, the Tarim block rapidly drifted to the north and rotated about 46 degrees clockwise. This process induced the collision of the Yili micro-continent with the eastern segment (present geographical position) of the Tarim continent in the Late Devonian, and the southern Tianshan oceanic crust evolved to be a west-facing remnant oceanic basin. During the Late Carboniferous-Early Permian, the Tarim block, located within an almost constant latitude range, rotated about 26 degrees clockwise with respect to the Yili micro-continent, which ultimately closed the remnant oceanic basin in a 'scissors-like' manner from east to west and completed the Tarim-Yili collision. Subsequent A-type subduction of the Tarim continental crust and lithosphere-scale sinistral shearing generated a magmatic are on the southern margin of the Tarim-Yili suture zone. The Late Permian-Early Triassic clastics deposited in a peripheral foreland basin developed above the are. (C) 1999 Elsevier Science B.V. All rights reserved.