Skip to Main content Skip to Navigation
Journal articles

The volcaniclastic series from the luang prabang basin, Laos: A witness of a triassic magmatic arc?

Abstract : The paleogeographic evolution of South East Asia (SEA) during the early Mesozoic is still poorly understood and a number of models have recently been put forward to account for the geodynamic evolution of SEA. The Luang Prabang Basin (north Laos), located in the core of a “paleogeographic jigsaw” in SEA, recorded a long lasting volcanism that spanned for ∼ 35 my from the earliest Triassic up to Late Triassic as evidenced by combined stratigraphic and geochronological (U-Pb/zircon) analyses performed on both volcanic and volcaniclastic series. The volcanic rocks are arc tholeiites and calk-alkaline andesites to dacites. The volcaniclastic rocks contain, in part, volcaniclasts produced contemporaneously with sedimentation. Both the volcanic and volcaniclastic series display geochemical features characteristic of a subduction related volcanism. Therefore, the Luang Prabang Basin documents a magmatic arc in a good agreement with the recent recognition of neighboring ophiolitic rocks in the Luang Prabang area. Following a passive margin setting that prevailed from the late Carboniferous to the late Permian, an active margin then initiated along the western margin of the Indochina Block. This active magmatic arc developed as the result of an east-dipping subduction below the Indochina Block during most of the Triassic, at least from ca. 250 to 215 Ma. Subsequently, this oceanic subduction episode must have been followed by a continental collision of the Indochina Block with the eastern Simao Block, at a period that remains to be defined.
Complete list of metadatas

Cited literature [120 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-01267172
Contributor : Isabelle Dubigeon <>
Submitted on : Thursday, February 4, 2016 - 9:32:37 AM
Last modification on : Thursday, March 5, 2020 - 11:56:11 AM
Long-term archiving on: : Saturday, November 12, 2016 - 7:38:00 AM

File

rossignol-2016.pdf
Files produced by the author(s)

Identifiers

Citation

Camille Rossignol, Sylvie Bourquin, Marc Poujol, Erwan Hallot, Marie-Pierre Dabard, et al.. The volcaniclastic series from the luang prabang basin, Laos: A witness of a triassic magmatic arc?. Journal of Asian Earth Sciences, Elsevier, 2016, 120, pp.159-183. ⟨10.1016/j.jseaes.2016.02.001⟩. ⟨insu-01267172⟩

Share

Metrics

Record views

265

Files downloads

3507