Assembly and dispersal history of continental blocks within the Altun-Qilian-North Qaidam mountain belt, NW China

The continental arc and intraplate magmatic rocks occur widely within the Altun-Qilian-North Qaidam (AQNQ) region of NW China and play a key role in reconstructing the assembly and dispersal history of micro-continental blocks within a complex orogenic system. In the South Qilian belt, amphibolites...

Full description

Saved in:
Bibliographic Details
Published in:International geology review 2019-03, Vol.61 (4), p.424-447
Main Authors: Fu, Changlei, Yan, Zhen, Guo, Xianqing, Niu, Manlan, Cao, Bo, Wu, Qi, Li, Xiucai, Wang, Zongqi
Format: Article
Language:English
Subjects:
Affinity
Amphibolite
Amphibolites
Assembly
Basalt
Continental margins
Dating
Depletion
Dispersal
Dispersion
Early Palaeozoic continental arc
Garnet
Geological time
Hualong Complex
Magma
Marine crustaceans
Neoproterozoic continental arc
Niobium
Orogeny
Precambrian
Radiometric dating
South Qilian belt
Tantalum
Tectonics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The continental arc and intraplate magmatic rocks occur widely within the Altun-Qilian-North Qaidam (AQNQ) region of NW China and play a key role in reconstructing the assembly and dispersal history of micro-continental blocks within a complex orogenic system. In the South Qilian belt, amphibolites from the Hualong Complex can be subdivided into four types based on their lithologies, ages, and tectonic affinities. Type I is characterized by garnet and Proterozoic detrital zircons, indicating a metasedimentary origin. Type II and IV amphibolites are tholeiitic and calc-alkaline, respectively, and characterized by enrichment in LREES, Th, U, and Ba, accompanied by depletion in Nb and Ta, indicating a continental arc setting on an active continental margin. Type III is alkaline with ocean island basalt affinity and considered to have intraplate, rift-related origins. SHRIMP U-Pb dating and previous studies suggest that type II, III, and IV amphiboltes are formed at 1126 Ma, 882 Ma, and 470 Ma, respectively, which corresponds to 1126-895 Ma continental arc magmatism, 882-580 Ma rifted-related magmatism, and 522-440 Ma continental arc magmatism within the AQNQ. The three episodes of magmatism further demonstrate the processes of assembly and breakup of the Proterozoic supercontinent Rodinia and reassembly of the Altun-Qilian-North Qaidam orogenic belt.
ISSN:0020-6814
1938-2839
DOI:10.1080/00206814.2018.1428831