BASIN ANALYSIS OF THE PALEOPROTEROZOIC PENRHYN AND PILING GROUPS, ARCTIC CANADA

The geological setting of the Paleoproterozoic Penrhyn and Piling basins in the western Churchill Province that closed in response to the Trans-Hudson Orogeny (THO) remains unresolved. An understanding of the nature and evolution of these basins (including mechanisms and timing of basin initiation, sediment sources, and mechanisms and timing of basin closure) is important when reconstructing the tectonics and paleogeography of the surrounding microcratonic blocks at that time.

Reconnaissance field mapping and geochronology of the Penrhyn and Piling groups (located on Melville Peninsula and Baffin Island, respectively) through the Geo-Mapping for Energy and Minerals Program (GEM), has allowed for a greater understanding of stratigraphic relationships between the Penrhyn and Piling groups. The evolution of the Penrhyn and Piling basins is inherently linked with the changing tectonic regimes associated with the THO. To that end, it is hypothesized that the Piling basin represents an extensional continental back-arc basin, which transitioned to a foreland basin during the protracted collision with the Meta Incognita craton. The record of the Penrhyn Group is more challenging to analyze, having experienced greater deformation and transposition, but likely experienced extension and subsidence from far-field tectonic stresses related to the Piling basin.

Comparing the stratigraphy and geochronology of the Penrhyn and Piling groups together allows for an integrated approach to understanding the basin evolution and potential metal endowment. Detailed stratigraphy, detrital zircon geochronology and geochemistry will be presented to elucidate the timing and nature of these basins.