Kam Group

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The Kam Group is a 10 km (6 mi) thick Archean volcanic group in the Yellowknife greenstone belt of the Northwest Territories, Canada. It consists of tholeiitic mafic and subordinate felsic volcanic rocks that were erupted in a submarine environment about 2706 million years ago.

The Archean Eon is one of the four geologic eons of Earth history, occurring 4,000 to 2,500 million years ago. During the Archean, the Earth's crust had cooled enough to allow the formation of continents and life started to form.

A volcanic group is a collection of related volcanoes or volcanic landforms. The term is also used in a different sense when it denotes a suite of associated rock strata largely of volcanic origin; see group (stratigraphy) for details.

The Yellowknife greenstone belt, also called the Yellowknife Volcanic Belt, is an Archean greenstone belt in the southern Slave craton, Northwest Territories, Canada. It is mostly made of mafic volcanic rocks and is bordered to the east by batholithic intrusions of the Western Granodiorite Complex and beyond to the north by the Duckfish Lake Granite. Intrusive equivalents are collectively known as the Kam Group. Most of the Yellowknife townsite and the Con and Giant gold mines are within the Kam Group. The Yellowknife greenstone belt stands out as a positive topographic feature.

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Greenstone may refer to:

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Slave Craton An Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut

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Volcanology of Canada

Volcanology of Canada includes lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calderas, diatremes, and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds. It has a very complex volcanological history spanning from the Precambrian eon at least 3.11 billion years ago when this part of the North American continent began to form.

Back River volcanic complex

The Back River volcanic complex is an Archean stratovolcano spanning the Northwest Territories–Nunavut border in Northern Canada. It is located 480 kilometres (298 mi) northwest of Yellowknife and to the northwest of the Back River from which it takes its name. The volcano constitutes the Back Group of the Yellowknife Supergroup and is somewhat anomalous in the Slave craton because it has undergone only a low degree of deformation and is subhorizontal. The southern half of the complex is exposed at the crest of a small dome. This is the eroded portion of the stratovolcano that has been preserved in an upright position. The complex comprises four volcanic sedimentary sequences that correspond to the phases of growth and destruction of this stratovolcano.

The Lac des Vents volcanic complex is a 2.3 km (1.4 mi) thick Archean volcanic complex in the Abitibi greenstone belt of Quebec, Canada. It is an important part of a major submarine volcanic structure.

Abitibi greenstone belt

The Abitibi greenstone belt is a 2,800-to-2,600-million-year-old greenstone belt that spans across the Ontario–Quebec border in Canada. It is mostly made of volcanic rocks, but also includes ultramafic rocks, mafic intrusions, granitoid rocks, and early and middle Precambrian sediments.

The Bird River greenstone belt is an Archean greenstone belt in southeastern Manitoba, Canada.

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The Rattlesnake Hills greenstone belt represents a fragment of a partially exposed synformal Archean greenstone belt within the Wyoming craton that was intruded by Cenozoic alkalic volcanics. The supracrustal belt has been subjected to multiphase deformation during the Archean and later brittle deformation during the Laramide orogeny. Ductile deformation during the Archean produced foliation, and at least three episodes of folding.

Volcanology of Eastern Canada

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Volcanology of Western Canada

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The Sherman volcano is a possible prehistoric volcano in the municipality of Temagami in Northeastern Ontario, Canada. Geological evidence indicates that it was located west of the abandoned Sherman Mine and lies in the Archean Temagami Greenstone Belt.

Tectonic evolution of the Barberton greenstone belt

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Archean felsic volcanic rocks

Archean felsic volcanic rocks are felsic volcanic rocks that were formed in the Archean Eon. The term "felsic" means that the rocks have silica content of 62–78%. Given that the Earth formed at ~4.5 billion year ago, Archean felsic volcanic rocks provide clues on the Earth's first volcanic activities on the Earth's surface started 500 million years after the Earth's formation.

The geology of Nunavut began to form nearly three billion years ago in the Archean and the territory preserves some of the world's oldest rock units.

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