Red Lake greenstone belt
Encyclopedia
The Red Lake greenstone belt is an Archean
Archean
The Archean , also spelled Archeozoic or Archæozoic) is a geologic eon before the Paleoproterozoic Era of the Proterozoic Eon, before 2.5 Ga ago. Instead of being based on stratigraphy, this date is defined chronometrically...

 greenstone belt
Greenstone belt
Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gneiss bodies....

 at the town of Red Lake
Red Lake, Ontario
Population trend:* Population in 2006: 4526* Population in 2001: 4233* Population total in 1996: 4778** Golden : 2248** Red Lake : 2277* Population in 1991:** Golden : 2355** Red Lake : 2268-Climate:...

 in Northwestern Ontario
Northwestern Ontario
Northwestern Ontario is the region within the Canadian province of Ontario which lies north and west of Lake Superior, and west of Hudson Bay and James Bay. It includes most of subarctic Ontario. Its western boundary is the Canadian province of Manitoba, which disputed Ontario's claim to the...

, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. It consists of basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic and komatiitic
Komatiite
Komatiite is a type of ultramafic mantle-derived volcanic rock. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content...

 volcanics ranging in age from 2,925 to 2,940 million years old and younger rhyolite
Rhyolite
This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...

-andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...

volcanics ranging in age from 2,730 to 2,750 million years old.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK