Quartz monzonite

Quartz monzonite
Igneous rock
	Quartz monzonite bedrock from a USGS drill core at western Cape Cod, Massachusetts

Quartz monzonite is an intrusive, felsic, igneous rock that has an approximately equal proportion of orthoclase and plagioclase feldspars. It is typically a light colored phaneritic (coarse-grained) to porphyritic granitic rock. The plagioclase is typically intermediate to sodic in composition, andesine to oligoclase. Quartz is present in significant amounts. Biotite and/or hornblende constitute the dark minerals. Because of its coloring, it is often confused with granite, but whereas granite contains more than 20% quartz, quartz monzonite is only 5–20% quartz. Rock with less than five percent quartz is classified as monzonite. A rock with more alkali feldspar is a syenite whereas one with more plagioclase is a quartz diorite.^[1] The fine grained volcanic rock equivalent of quartz monzonite is quartz latite.^[1]

The term adamellite was originally applied by A. Cathrein in 1890 to orthoclase-bearing tonalite (likely a granodiorite) at Monte Adamello, Italy, in 1890, but later came to refer to quartz monzonite. The term is now deprecated.^[2]

Quartz monzonite porphyry is often associated with copper mineralization in the porphyry copper ore deposits.^[3]

Geographic distribution

United States

In the White Mountains and western highlands of New Hampshire, the Kinsman Quartz Monzonite is an extensive formation that underlies Kinsman Mountain, parts of Franconia Notch, Mount Cardigan, and Mount Sunapee.^[4]

Stone Mountain in Georgia is a large quartz monzonite monadnock.^{[citation needed]}

Quartz monzonite extracted from a quarry in Little Cottonwood Canyon was used to build several buildings in Salt Lake City, Utah, including the Church of Jesus Christ of Latter-day Saints' Salt Lake Temple, Church Administration Building, and Conference Center, as well as the Utah State Capitol.^{[citation needed]}

The large boulders of Joshua Tree National Park in southern California are quartz monzonite.^{[citation needed]}

A large pluton in the Atlanta lobe of the Idaho Batholith, near McCall, Idaho, is made of quartz monzonite.^[5]

The Guilford Quartz Monzonite and Woodstock Quartz Monzonite, probably comagmatic, are located in central Maryland.^{[citation needed]}

Australia

In Queensland, Castle Hill, Mount Stuart and Mount Louisa around Townsville represent a large quartz monzonite province.^{[citation needed]}

References

^ ^a ^b Classification of Igneous Rocks Archived September 30, 2011, at the Wayback Machine
^ Streckeisen, A. (1 March 1976). "To each plutonic rock its proper name". Earth-Science Reviews. 12 (1): 1–33. doi:10.1016/0012-8252(76)90052-0.
^ Titley, Spencer R. and Carol L. Hicks, Geology of the Porphyry Copper Deposits, University of Arizona Press, 1966, p. 35
^ Billings, M.P. (1956). "The Geology of New Hampshire: Part II – Bedrock Geology". ngmdb.usgs.gov. New Hampshire State Planning and Development Commission. Retrieved September 17, 2020.
^ Idaho Batholith

External links

Media related to Quartz monzonite at Wikimedia Commons

[IUGS-1] Classification of Igneous Rocks Archived September 30, 2011, at the Wayback Machine

[2] Streckeisen, A. (1 March 1976). "To each plutonic rock its proper name". Earth-Science Reviews. 12 (1): 1–33. doi:10.1016/0012-8252(76)90052-0.

[3] Titley, Spencer R. and Carol L. Hicks, Geology of the Porphyry Copper Deposits, University of Arizona Press, 1966, p. 35

[4] Billings, M.P. (1956). "The Geology of New Hampshire: Part II – Bedrock Geology". ngmdb.usgs.gov. New Hampshire State Planning and Development Commission. Retrieved September 17, 2020.

[5] Idaho Batholith

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v t e Types of rocks
Igneous rock	Adakite Andesite Alkali feldspar granite Anorthosite Aplite Basalt Alkali basalt Picrite basalt Basaltic trachyandesite Mugearite Shoshonite Basanite Blairmorite Boninite Carbonatite Charnockite Enderbite Dacite Diabase Diorite Napoleonite Dunite Essexite Foidolite Gabbro Granite Granodiorite Granophyre Harzburgite Hornblendite Hyaloclastite Icelandite Ignimbrite Ijolite Kimberlite Komatiite Lamproite Lamprophyre Latite Lherzolite Monzogranite Monzonite Nepheline syenite Nephelinite Norite Obsidian Pegmatite Peridotite Phonolite Phonotephrite Porphyry Pumice Pyroxenite Quartz diorite Quartz monzonite Quartzolite Rhyodacite Rhyolite Comendite Pantellerite Scoria Shonkinite Sovite Syenite Tachylyte Tephriphonolite Tephrite Tonalite Trachyandesite Benmoreite Trachybasalt Hawaiite Trachyte Troctolite Trondhjemite Tuff Websterite Wehrlite
Sedimentary rock	Argillite Arkose Banded iron formation Breccia Calcarenite Chalk Chert Claystone Coal Conglomerate Coquina Diamictite Diatomite Dolomite Evaporite Flint Geyserite Greywacke Gritstone Itacolumite Jaspillite Laterite Lignite Limestone Lumachelle Marl Mudstone Oil shale Oolite Phosphorite Sandstone Shale Siltstone Sylvinite Tillite Travertine Tufa Turbidite Varve Wackestone
Metamorphic rock	Anthracite Amphibolite Blueschist Cataclasite Eclogite Gneiss Granulite Greenschist Hornfels Calcflinta Itabirite Litchfieldite Marble Migmatite Mylonite Metapelite Metapsammite Phyllite Pseudotachylite Quartzite Schist Serpentinite Skarn Slate Suevite Talc carbonate Soapstone Tectonite Whiteschist
Specific varieties	Adamellite Appinite Aphanite Borolanite Blue Granite Epidosite Felsite Flint Ganister Gossan Hyaloclastite Ijolite Jadeitite Jasperoid Kenyte Lapis lazuli Larvikite Litchfieldite Llanite Luxullianite Mangerite Novaculite Pietersite Pyrolite Rapakivi granite Rhomb porphyry Rodingite Shonkinite Taconite Tachylite Teschenite Theralite Unakite Variolite Wad