The Spi Group: a post-Archean, pre-2.1 Ga rift succession, Trans-Hudson hinterland

Autor: Judith G. Patterson
Rok vydání: 1991
Předmět:
Zdroj: Canadian Journal of Earth Sciences. 28:1863-1872
ISSN: 1480-3313
0008-4077
Popis: A succession of mafic flows intercalated with sandstone and overlain by conglomerate, herein named the Spi Group, lies unconformably on Archean basement and is preserved in a syncline near Spi Lake, N.W.T. An alluvial fan setting near active rift fault escarpments is the interpreted environment of deposition. The nearby Montgomery Lake Group, Mackenzie Lake metasediments, and Padlei Formation at the base of the Hurwitz Group are possible correlatives of the Spi Group; diabase dykes of the Kaminak swarm, common in the Archean basement, are possibly related to the mafic flows. Correlation with the upper, coarse clastic part of the Hurwitz Group (Tavani Formation) is discounted because the Spi conglomerate does not contain clasts of Hurwitz lithology. The Montgomery Lake, Padlei and Spi successions are interpreted as being rift-related, and are older than the 2.1 Ga gabbro that intrudes the Hurwitz Group. Recognition of widespread rifting in this part of the Hearne Province constrains tectonic modelling of the preorogenic history of the Trans-Hudson hinterland.
Databáze: OpenAIRE