Premium
The Zoulang Nanshan Caledonian Subduction Complex in the Northern Qilian Mountains and Its Dynamics 1
Author(s) -
Zhiqin Xu,
Huifen Xu,
Jianxin Zhang,
Haibing Li,
Zhizhi Zhu,
Jingchuan Qu,
Daizhang Chen,
Jinlu Chen,
Kaichun Yang
Publication year - 1994
Publication title -
acta geologica sinica ‐ english edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.444
H-Index - 61
eISSN - 1755-6724
pISSN - 1000-9515
DOI - 10.1111/j.1755-6724.1994.mp7003001.x
Subject(s) - geology , subduction , forearc , terrane , accretionary wedge , ophiolite , flysch , accretion (finance) , volcanic arc , oceanic crust , seismology , metamorphism , block (permutation group theory) , island arc , geochemistry , petrology , tectonics , physics , geometry , mathematics , astrophysics
The front of the Zoulang Nanshan Caledonian volcanic island arc zone in the northern Qilian Mountains is a forearc accretionary terrane, composed of multiple accretionary volcanic island arcs, flysch accretionary wedges, high ‐ pressure metamorphosed detachment zones and remnants of ophiolites. It resulted from the northeastward subduction of the Early Palaeozoic Qilan oceanic crust beneath the Alxa block. High ‐ pressure metamorphism, which occurred during the subduction, progressed through three stages: the initial stage of medium T ‐ high P, the main stage of temperature decrease and pressure increase, and the lag stage of pressure decrease and temperature increase. Finally the paper presents a retrotrench subduction dynamic model indicative of northward subduction of the central Qilian block and southward accretion of the Alxa block during the period of 450‐500 M a.