Orogenic belt resulting from ocean-continent collision

Zhao，Jun Hong1; Yang，Ting2; Wang，Wei1

2022-11-01

10.1130/G50337.1

GEOLOGY   Impact Factor & Quartile

0091-7613

1943-2682

Orogenic belts have been thought to form through plate convergence, involving subduction of oceanic lithosphere at continental margins (accretionary orogens), which may ultimately lead to ocean closure and continent-continent collision (collisional orogens). Intraplate orogens away from plate margins have been known, but the mechanisms controlling their evolution are poorly understood. The South China craton, including the Yangtze and Cathaysia blocks, underwent a Paleozoic orogenesis that formed a >500-km-wide orogenic belt with widespread granitoids that are unconformably overlain by Devonian cover sequences. The pre-Devonian basement rocks were subjected to strong deformation and greenschist to amphibolite-facies metamorphism at 460–400 Ma. Paleozoic magmatism was characterized by voluminous crustally derived Silurian granitoids associated with incorporation of ancient crustal materials at 450–440 Ma and addition of juvenile mantle-derived melts at 420–410 Ma. Based on the absence of arc-like magmatism and the existence of ophiolites in the West Cathaysia terrane, geochemical evidence that oceanic crust existed beneath the East Cathaysia terrane, and geophysical evidence of contrasting lithospheres on both sides and two discrete slabs beneath their fault boundary, we propose that this Paleozoic orogenic belt was formed by collision between the two terranes that was driven by far-field forces during the assembly of Gondwana, and the East Cathaysia terrane represents oceanic lithosphere that was overthrusted by the continental crustal materials of the West Cathaysia terrane. Numerical modeling shows that this type of collision can explain the dynamics of the Paleozoic orogenesis in the South China craton and may be a mechanism for some orogens in which subduction-related igneous and metamorphic rocks are lacking

EI ; SCI

English

NI Journal Papers

Others

National Natural Science Foundation of China[42025203];

Geology

Geology

WOS:000886619800012

GEOLOGICAL SOC AMER, INC

20224613115592

Igneous rocks ; Structural geology

Geology:481.1

GEOSCIENCES

2-s2.0-85141762915

Scopus

1.State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan,430074,China
2.Department of Earth and Space Sciences,Southern University of Science and Technology,Shenzhen,518055,China

Zhao，Jun Hong,Yang，Ting,Wang，Wei. Orogenic belt resulting from ocean-continent collision[J]. GEOLOGY,2022,50(11):1266-1269.

Zhao，Jun Hong,Yang，Ting,&Wang，Wei.(2022).Orogenic belt resulting from ocean-continent collision.GEOLOGY,50(11),1266-1269.

Zhao，Jun Hong,et al."Orogenic belt resulting from ocean-continent collision".GEOLOGY 50.11(2022):1266-1269.