The Grès Singuliers of the Mont Blanc region (France and Switzerland): stratigraphic response to rifting and crustal necking in the Alpine Tethys

The Grès Singuliers unit represents an anomalous occurrence of a siliciclastic-dominated sedimentary system typifying a restricted geographic area around the Mont Blanc massif. Deposited during Early Jurassic rifting, this unit was influenced by the tectonic processes responsible for its development...

Full description

Saved in:
Bibliographic Details
Published in:International journal of earth sciences : Geologische Rundschau 2020-10, Vol.109 (7), p.2325-2352
Main Authors: Ribes, Charlotte, Ghienne, Jean-François, Manatschal, Gianreto, Dall’Asta, Nicolas, Stockli, Daniel F., Galster, Federico, Gillard, Morgane, Karner, Garry D.
Format: Article
Language:English
Subjects:
Earth and Environmental Science
Earth Sciences
Geochemistry
Geology
Geophysics/Geodesy
Jurassic
Magma
Massifs
Mineral Resources
Original Paper
Passive margins
Provenance
Rift zones
Rifting
Sciences of the Universe
Sedimentary facies
Sedimentology
Stratigraphy
Structural Geology
Tectonic processes
Tectonics
Uplift
Zircon
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The Grès Singuliers unit represents an anomalous occurrence of a siliciclastic-dominated sedimentary system typifying a restricted geographic area around the Mont Blanc massif. Deposited during Early Jurassic rifting, this unit was influenced by the tectonic processes responsible for its development. This contribution integrates and reconciles sedimentological, stratigraphic and tectonic data and discusses the tectono-sedimentary evolution of the Mont Blanc basement and its autochthonous sedimentary cover. Based on depositional facies, a petrographic and detrital zircon provenance analysis, we propose that the Grès Singuliers unit is mainly derived from erosion of the local basement and pre-rift sedimentary cover. Furthermore, recognition of Jurassic cataclasites and black gouges capping the Mont Blanc basement confirms the hypothesis that the Mont Blanc domain formed an extensional core complex. The source to sink relationship between the Mont Blanc detachment system and the Grès Singuliers unit, as well as timing and location within the Alpine rift system, allows us to interpret this unit as the syn-tectonic sedimentary response to crustal necking, responsible for the onset of localized severe crustal/lithospheric thinning in the European margin of the Alpine Tethys rift system. The main result of this study was to show that the exhumation and uplift of basement during crustal/lithospheric necking produced a new source area for clastic sedimentary systems. Therefore, the local occurrence of a siliciclastic unit similar to the Grès Singuliers along passive margins may be symptomatic of necking zones in other rift systems.
ISSN:1437-3254
1437-3262
DOI:10.1007/s00531-020-01902-z