The South China Block-Indochina collision: where, when, and how? - Archive ouverte HAL Access content directly
Journal Articles Journal of Southeast Asian earth sciences Year : 2014

The South China Block-Indochina collision: where, when, and how?

(1) , (2) , (3) , (4) , (4)
1
2
3
4

Abstract

This study uses new field observations and existing studies to shed new light on the origin and significance of two NW-SE striking orogens in NW and NE Vietnam. We conclude that the architecture of each belt is a stack of NE-directed nappes formed either under deep ductile synmetamorphic conditions, or under shallow depth in the SW and NE parts, respectively. The Song Ma zone and Song Chay ophiolitic melange represent two ophiolitic sutures. However, the Late Permian Song Da and Babu mafic rocks are not ophiolites but intraplate basalts related to the Emeishan plume. A Late Triassic unconformity, the 225-205 Ma postorogenic plutonism, and the 250-230 Ma syntectonic metamorphism support an Early to Middle Triassic age for these tectonic events. Both NW and NE belts are due to SW-directed subduction with arc magmatism, ocean closure, and continental collision. Though two contemporary S-dipping subduction zones might explain the structural evolution of the two belts, a single convergent system, offset by the Tertiary Red River fault, is preferred as this S-directed subduction better accounts for the Late Permian intraplate magmatism. This scenario is discussed in the general geodynamic framework of SE Asia.
Vignette du fichier
Fig_1_map.jpg (196.28 Ko) Télécharger le fichier Fichier principal
Vignette du fichier
Final_text_SCB-Indo_collision_copie.pdf (6.42 Mo) Télécharger le fichier
Format : Figure, Image
Origin : Files produced by the author(s)
Loading...

Dates and versions

insu-00863348 , version 1 (18-09-2013)

Identifiers

Cite

Michel Faure, Claude Lepvrier, Nguyen van Vuong, Wei Lin, Zechao Chen. The South China Block-Indochina collision: where, when, and how?. Journal of Southeast Asian earth sciences, 2014, 79, pp.260-274. ⟨10.1016/j.jseaes.2013.09.022⟩. ⟨insu-00863348⟩
313 View
2197 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More