The Huronian Supergroup is a

Proterozoic The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided ...

assemblage of geologic formations of the

Superior craton The Superior Craton is a stable crustal block covering Quebec, Ontario, and southeast Manitoba in Canada, and northern Minnesota in the United States. It is the biggest craton among those formed during the Archean period. A craton is a large part ...

of the

Canadian Shield The Canadian Shield (french: Bouclier canadien ), also called the Laurentian Plateau, is a geologic shield, a large area of exposed Precambrian igneous and high-grade metamorphic rocks. It forms the North American Craton (or Laurentia), the anc ...

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

and

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

. It extends from west of the city of

Sault Ste. Marie Sault Ste. Marie is a cross-border region of Canada and the United States located on St. Marys River, which drains Lake Superior into Lake Huron. Founded as a single settlement in 1668, Sault Ste. Marie was divided in 1817 by the establishment of ...

in the west to the Ontario-Quebec border to the east and is part of the Southern Geologic Province. Stratigraphy The Huronian Supergroup consists of four Groups. All the rocks are low grade metamorphic sedimentary rocks or igneous rocks. The four geologic groups that make up the Huronian are the Elliot Lake Group, Hough Lake Group, Quirke Lake Group, and the Cobalt Group (from oldest to youngest). Major glacial periods,

Huronian glaciation The Huronian glaciation (or Makganyene glaciation) was a period where several ice ages occurred during the deposition of the Huronian Supergroup, rather than a single continuous event as it is commonly misrepresented to be. The deposition of thi ...

, occurred at the beginning of the Hough Lake,

Quirke Lake Quirke Lake is body of water located in Ontario, Canada. It is located in the Quirke Lake basin, a geological basin the northern part of the Huronian Supergroup. The lake is proximate to five decommissioned uranium mines. Location The lake is l ...

and Cobalt. Age The bulk of the Huronian Group consists of mostly metamorphosed sandstones and mudstones. Since there are no index fossils, the sedimentary rocks cannot be dated using fossils, like they can in

Phanerozoic The Phanerozoic Eon is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 538.8 million years to the present, and it began with the Cambrian Period, when anima ...

rocks. However, the base contains volcanics that have been dated at about 2.480 billion years ago (Gya). The top of the Huronian and cross cutting all of the units within are the Nipissing sills which date to 2.2185 Gya. The age at which the Huronian sediments were deposited is between 2.480 Gya and 2.219 Gya.

References

Geology of Ontario Geology of Quebec {{Canada-geologic-formation-stub

See also

References