The Noranda Caldera is a well-known large subaqueous

Archean The Archean ( , also spelled Archaean or Archæan), in older sources sometimes called the Archaeozoic, is the second of the four geologic eons of Earth's history of Earth, history, preceded by the Hadean Eon and followed by the Proterozoic and t ...

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...

complex not too far from

Rouyn-Noranda, Quebec Rouyn-Noranda (; 2021 population 42,313) is a city on Osisko Lake in the Abitibi-Témiscamingue region of Quebec, Canada. The city of Rouyn-Noranda is coextensive with a territory equivalent to a regional county municipality (TE) and census ...

within the Blake River Megacaldera Complex. The caldera contains a 7-to-9-km-thick succession of bimodal

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

felsic In geology, felsic is a grammatical modifier, modifier describing igneous rocks that are relatively rich in elements that form feldspar and quartz.Marshak, Stephen, 2009, ''Essentials of Geology,'' W. W. Norton & Company, 3rd ed. It is contrasted ...

tholeiitic The tholeiitic magma series () is one of two main magma series in subalkaline igneous rocks, the other being the calc-alkaline series. A magma series is a chemically distinct range of magma compositions that describes the evolution of a mafic ...

to calc-

alkaline In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The ...

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

s which were erupted during five major series of volcanic activity.ASH FALL: Newsletter of the Volcanology and Igneous Petrology Division Geological Association of Canada
Retrieved on 2007-09-22 The metallogenic impact of the Noranda Caldera is well-known, but the importance of the New Senator Caldera and Misema Caldera remains to be evaluated.

References

Calderas of Quebec Archean calderas Polygenetic volcanoes Landforms of Abitibi-Témiscamingue {{AbitibiTémiscamingue-geo-stub

See also

References