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TECTONICS,
VOL. 2, NO. 2,
PAGES 139–166,
1983
SPECULATIONS ON THE MESOZOIC PLATE TECTONIC EVOLUTION OF EASTERN CHINA
Michael P. Klimetz
Department of Geological Sciences, State University of New York at Albany, Albany, New York 12222
Abstract
Several orogenic belts transecting eastern China are the sites of former convergent plate margins, although there have been
varying views on the collisional framework of individual continental blocks, styles of convergence at these zones, and the
timing of respective collisions. A tectonic study of eastern China, Mongolia and the southern Soviet Far East indicates the
collision of the South China Block with a combined North China-Northeast China Fold Zone Block in the Late Triassic-Early
Jurassic, their collective suturing to Eurasia in the Late Jurassic-Early Cretaceous, followed by the Sikhote Alin-Japan Block
in the Mid to Late Cretaceous. The evidence is as follows: (1) A linear belt of Late Triassic-Early Cretaceous granites and
granodiorites trends east from the Qinlingshan through the Dabieshan to the Huaiyang massif. Ophiolites, flysch, subduction
zone melange, a paired metamorphic belt indicating north dipping subduction and marine strata of Carboniferous to Late Triassic
age from the Qinlingshan define the suture between the North and South China Blocks, (2) A sinuous belt of ultramafics, blueschists,
silicic to intermediate magmatism and west and north vergent folds and thrusts trend from the west margin of the Ordos Basin
through central Inner Mongolia and along the east Great Khingan Range to the Amur River. Coupled with a Mid Jurassic-Early
Creataceous unconformity a suturing of eastern Chinese blocks to Eurasia along this zone is suggested, (3) A fold and thrust
belt with ultramafics, flysch, blueschists and subduction zone melange along the Ussuri River in northeast China indicates
the suturing of the Sikhote Alin-Japan Block to Eurasia along a west dipping subduction zone in the Mid to Late Cretaceous.
Similarly, a tectonic study of southern China and Southeast Asia has revealed a complex regional mosaic of suture-bounded
terrains which nucleated about the eastern, western and southern margins of the Yangtze Craton during the Late Triassic and
Early Jurassic. The evidence is as follows: (4) A north–south trending belt of ophiolites, blueschists, calc-alkaline volcanics
and subduction zone melange, including granites, granodiorites arid strongly deformed marine strata all of Late Triassic age
exposed in the Longmenshan of Sichuan merge with the Kekexilishan ophiolite zone Into the Ailaoshan-Tengtiaohe ophiolite and
blueschist belt in central Yunnan along which the Songban-Ganzi Complex and the Shan-Thai-Malaya Block join the Craton, and
(5) A southeastern prolongation of the Ailaoshan-Tengtiaohe belt bifurcates into the southeast trending Konvoi zone of northern
Vietnam and the north–south trending Pak Lay-Luang Prabang zone of Laos and eastern Thailand. Zones of ophiolite, calc-alkaline
volcanics and strong Late Triassic deformation, they separate the Indosinia and Shan-Thai-Malaya Blocks from the Craton respectively.
These findings differ significantly from previous interpretations of a Late Paleozoic consolidation of South–Eastern Asia
as well as disputing the existence of a true Pangea.
Received 19
November
1982;
accepted 3
March
1983.
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Citation: Klimetz, M. P.
(1983),
SPECULATIONS ON THE MESOZOIC PLATE TECTONIC EVOLUTION OF EASTERN CHINA,
Tectonics,
2(2),
139–166.
Copyright 1983 by the American Geophysical Union.
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