John Menzies; Microstructures in Diamictites of the Lower Gowganda Formation (Huronian), Near Elliot Lake, Ontario: Evidence for Deforming-Bed Conditions at the Grounding Line?. Journal of Sedimentary Research ; 70 (1): 210–216. doi: https://doi.org/10.1306/2DC4090B-0E47-11D7-8643000102C1865D
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Diamictites examined in the lower Gowganda Formation (2.5-2.2 Ga) to the north of Elliot Lake reveal a large number of macrostructures and microstructures. From micromorphological analyses the microstructures show a group of structures indicative of both ductile and brittle deformation likely developed during glacial sedimentation. The diamictites possibly were deposited in a proximal subglacial or subaqueous environment as a product of soft deforming-bed sediments being extruded beneath an active ice sheet at its grounding-line margin as it entered a marine basin. This is the first known example of glacial deforming-bed conditions being shown to have possibly developed beneath Precambrian ice sheets.