Acid igneous rocks

Granite

Acidic igneous rocks ( silica-igneous igneous rocks ) - a detachment of igneous rocks distinguished by the content of silica (SiO ₂ ), which varies from 63-78%. The rock-forming minerals of the order are quartz , potassium feldspars , acid plagioclases , biotite , less often muscovite , hornblende and augite . Of the accessory minerals, zircon and tourmaline are typical.

The characteristic representatives of acidic rocks of the plutonic class are granodiorites , plagiogranites , granites ; volcanic class - rhyolites , dacites . The squad distinguishes 16 families and 33 species of rocks. Of these, 9 families and 18 species fall on the plutonic class, 7 families and 15 types of rocks on the volcanic class.

Content

Classification

The classification of acidic igneous rocks was developed and approved by the Interdepartmental Petrographic Committee of Russia and published in the Petrographic Code of Russia ^[1] as part of the general classification tables of igneous (volcanic and plutonic) rocks .

Plutonic rock class	Class of hypabyssal breeds	Volcanic rock class
Normally alkaline suborder : Family of granodiorites: Tonalit ; Granodiorite . Granite Family: Plagiogranite (trondjemite); Granite Leucogranite Family: Leukoplagiogranitis; Leukogranit . Moderately alkaline suborder : Granosyenite family: Granosyenite (syenogranite). Family of moderate alkaline granites: Monzogranit (adamellite); Alkaline feldspar granite; Microcline-albite granite. Family of moderate alkaline leukogranites: Monzoleic granite; Alaska Microcline-albite leukogranite. Alkaline suborder : Alkaline granosyenite family: Alkaline granosyenitis; Alkaline Granite Family: Alkaline monzogranit; Alkaline microcline-albite granite. Alkaline Leukogranite Family: Alkaline Alaskite; Alkaline microcline-albite leukogranite.	aplit	Normally alkaline suborder : Dacite family: Plagiodacitis; Dacite . Rhodocyte family: Plagioriodacitis; Riodacitis. Rhyolite Family: Plagioriolitis; Riolite . Moderately alkaline suborder : Trachidocyte Family: Trachidacitis. Trachiriodacyte Family: Trachiriodacitis; Alkaline feldspar trachioriodacitis; Ongonite . Trachyriolite Family: Trachyriolite; Alkaline feldspar trachioriolitis; Ongoriolit. Alkaline suborder : Family of Pantellerites - Commandids: Pantelleritis (alkaline rhyodacite); Komendit (alkaline rhyolite).

The Evolution of Sour Magma

Acid Magma Generation and Differentiation

Acid Rock Associations

Acid metallogeny

Sour Moon rocks

Notes

↑ Petrographic Code, 2009 , p. 103-152.

Links

Acidic rocks in GeoWiki

Literature

Igneous rocks in six volumes [Sat. ] / Ed. O. A. Bogatikova . - M .: Nauka , 1983. - T. 1: Classification, nomenclature, petrography. - 768 p. - 2600 copies.
Igneous rocks in six volumes [Sat. ] / Ed. O. A. Bogatikova . - M .: Nauka , 1987. - T. 4: Acid and medium rocks. - 375 p. - 1750 copies.
Petrographic Code of Russia: Magmatic, Metamorphic, Metasomatic, Impact Formations / Ed. O. A. Bogatikova , O. V. Petrova, A. F. Morozov; open ed. L.V. Sharpenok. - 3rd ed., Rev. and additional .. - St. Petersburg. : VSEGEI , 2009 .-- 200 p. - 500 copies.

[_122536d8145feb12-1] Petrographic Code, 2009 , p. 103-152.