A drastic lower Miocene regolith evolution triggered by post obduction slab break-off and uplift in New Caledonia

Brice Sevin 1, 2 Dominique Cluzel 2 Pierre Maurizot 3 Caroline Ricordel-Prognon 3, 4 George Chaproniere 5 Nicolas Folcher 2 Florence Quesnel 3, 4
1 Geological Survey of New Caledonia
2 PPME - EA 3325 - Pôle Pluridisciplinaire de la Matière et de l'Environnement
3 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
4 ISTO - Institut des Sciences de la Terre d'Orléans - UMR7327
5 ANU - Australian National University
Abstract : A lower Miocene coarse conglomerate that crops out in the Népoui Peninsula does not represent the base of the marine transgression that followed obduction in New Caledonia. Instead, the conglomeratic alluvial fan that contains peridotite cobbles and reworked weathering products records a short-lived episode of terrestrial erosion intercalated between two intervals of subsidence marked by marine carbonate deposition. Considering the Miocene sea level evolution reported in the literature, it is concluded that neither lower Miocene transgression nor erosion were driven by sea level variation. In contrast, a southeastward propagating slab tear that initiated at the latitude of the high pressure/low temperature metamorphic complex of northern New Caledonia likely generated east to west tilting of New Caledonia, subsidence along the West Coast and hence fringing reef development together with moderate erosion of older regolith. Coincidence between conglomerate deposition and hence prominent erosion that closely followed emplacement of postobduction granitoids influenced by a slab window suggests a genetic link. Therefore, it is concluded that short-lived lower Miocene erosion was due to slab breakoff and subsequent uplift that occurred at ~ 22 Ma. Lower Miocene erosion profoundly dissected the Peridotite Nappe and in the northern half of New Caledonia only left isolated klippes along the West Coast.
Type de document :
Article dans une revue
Tectonics, American Geophysical Union (AGU), 2014, 33 (9), pp.1787-1801. 〈10.1002/2014TC003588〉
Liste complète des métadonnées

Littérature citée [67 références]  Voir  Masquer  Télécharger
https://hal-brgm.archives-ouvertes.fr/hal-01171278
Contributeur : Anne-Marie Pouget <>
Soumis le : mardi 28 juillet 2015 - 13:32:41
Dernière modification le : mardi 16 octobre 2018 - 01:01:34
Document(s) archivé(s) le : jeudi 29 octobre 2015 - 10:53:02

Fichier

Sevin_et_al-2014-Tectonics.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Collections

BRGM | UNIV-ORLEANS | ISTO | INSU | OSUC

Citation

Brice Sevin, Dominique Cluzel, Pierre Maurizot, Caroline Ricordel-Prognon, George Chaproniere, et al.. A drastic lower Miocene regolith evolution triggered by post obduction slab break-off and uplift in New Caledonia. Tectonics, American Geophysical Union (AGU), 2014, 33 (9), pp.1787-1801. 〈10.1002/2014TC003588〉. 〈hal-01171278〉

Exporter

BibTeX TEI DC DCterms EndNote

Partager

Métriques

Consultations de la notice

170

Téléchargements de fichiers

152

Contact

support.ccsd.cnrs.fr
hal.support@ccsd.cnrs.fr
Logo CCSD