The early Neoproterozoic Chandindu Formation of the Fifteenmile Group in the Ogilvie Mountains

• Main Authors: Kunzmann, Marcus, Halverson Galen, P., Hodgskiss, Malcolm, Sansjofre, Pierre, Schumann, Dirk, Macdonald, Francis A., Rainbird, Robert H
• Other Authors: Department of Earth and Planetary Sciences/Geotop, McGill University = Université McGill Montréal, Canada, Domaines Océaniques (LDO), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Department of Earth and Planetary Sciences Cambridge, USA (EPS), Harvard University Cambridge, Geological Survey of Canada Ottawa (GSC Central & Northern Canada), Geological Survey of Canada - Office (GSC), Natural Resources Canada (NRCan)-Natural Resources Canada (NRCan)
• Format: Other/Unknown Material
• Language: English
• Published: HAL CCSD 2014
• Subjects: geo; archeo; Canada; Hart River; Ogilvie; Ogilvie Mountains; Yukon
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-00985324

Annual Report Yukon Exploration and Geology 2013 Studies of biogeochemical and evolutionary change in the Neoproterozoic require a detailed understanding of stratigraphic successions and their intrabasinal correlation to integrate those records into regional and global frameworks. The early Neoproterozoic Fifteenmile Group in the Ogilvie Mountains has previously been shown to archive important information on the evolution of the biosphere, including ocean redox and early evolution of eukaryotes. Here, we formally define the Chandindu Formation, a 150 to 420-m-thick siltstone-dominated mixed carbonate-siliciclastic succession of the lower Fifteenmile Group in the Coal Creek and Hart River inliers. We present ten sections of the Chandindu Formation and propose a type section and formalization to promote the development of a consistent stratigraphic framework for Proterozoic successions in northwest Canada. The Chandindu Formation begins with muddy tidal flat facies, which are succeeded by shale-siltstonesandstone coarsening-upward cycles deposited in a predominantly subtidal environment. However, carbonate occurrences throughout the entire unit suggest localized carbonate buildups, likely nucleated on fault-bound paleohighs where siliciclastic background sedimentation was low. These paleohighs originated from rift-inherited complex basin topography and syn-depositional faulting during deposition of the upper Chandindu Formation.