Research about Gowganda Formation

USGS1971

Glacial marine sediments in the precambrian Gowganda formation at Whitefish Falls, Ontario (Canada)

Study of a well-exposed section of the Gowganda Formation at Whitefish Falls, Ontario, suggests criteria for the recognition of glacial marine sediments. Thickness of hundreds of feet, lateral continuity, faint internal stratification, sorted lenses of sandstone and conglomerate, and dropstones characterize much of the tillite. Thickness of hundreds of feet, lateral continuity, and marked development of irregular and lenticular laminae instead of varve structure characterize much of the argillite. These characteristics, together with evidence for a nearshore, marine-to-deltaic environment for the overlying beds, suggest a glacial marine interpretation even though no fossil evidence is available. Massive tillite, tillite containing faint stratification and lenses of sorted conglomerate and sandstone, and dropstone-bearing argillite, all of which interfinger, suggest a glacial marine environment composed of: ( 1 ) a subglacial facies; ( 2 ) a periglacial facies; and ( 3 ) a facies of marine ice rafting, respectively. Separation of the two tillite-bearing members by as much as 700 ft. of argillite containing no dropstones suggests two distinct ice ages during Gowganda time.

Ontario↗

USGS1969

Glacial sedimentology of the Precambrian Gowganda Formation, Ontario, Canada

The Gowganda Formation is part of the thick Huronián sequence of Precambrian sedimentary rocks that crop out in central Ontario from Lake Superior to Quebec. Although it has long been considered to be glacial, recent work on submarine slump and turbidite deposits has reopened the question of its origin. This study was made to determine its origin and paleogeography. Till-like conglomerates, varved argillites, and abundant dropstones characterize the Gowganda and provide strong evidence for a glacial origin. Pebble fabric parallel to regional paleocurrents, rare striated and grooved pavements, and abundant unweathered detritus are also in harmony with a glacial origin. Local thin-bedded sandstones contain flame structure, graded bedding, contorted bedding, and rippled tops, suggesting deposition by turbidity flows. Association of these sandstones with varved argillites and rafted stones indicates that Gowganda turbidites are glaciolacustrine. Along the southern margin of the Gowganda, at Whitefish Falls, thick, laterally continuous till-like conglomerates contain internal stratification indicative of subaqueous deposition. Argillites that lack varved structure and associated silty limestones suggest a glacial marine environment. In the Cobalt region the apparent long axes of pebbles in conglomerates show a predominant north-south alignment. In the Bruce Mines-Elliot Lake region, the orientation of the long axes of pebbles is more variable. Differences in orientation are related to stratigraphic position. Ripple cross-lamination in sandstones that are interbedded with argillite indicates south-trending paleocurrents. Distribution of varved argillite, silty limestone, and probable marine argillites suggests a northern fresh-water facies and a southern marine facies. Abundant plutonic pebbles and feldspar indicate that the Gowganda ice sheets eroded a northern plutonic terrane and deposited much of their sediment load on the underlying Huronian sediments to the south.

Ontario↗

USGS1966

Sediment transport in a Precambrian ice age: The Huronian Gowganda Formation

The Gowganda Formation of Ontario consists of conglomerates, quartzites, and argillites deposited in a glacial environment. The distribution of varved argillites and silty limestones suggests continental and marine facies, respectively. Pebble and ripple-drift orientations, distribution of limestones, striated pavements, distribution of the underlying Bruce Group, and Huronian quartzite paleocurrents support the conclusion that sediment transport was from north to south.

Ontario↗