Intermediate composition

In igneous petrology an intermediate composition refers to the chemical composition of a rock that has 52-63 wt% SiO₂ being an intermediate between felsic and mafic compositions. Typical intermediate rocks include andesite, dacite and trachyandesite among volcanic rocks and diorite and granodiorite among plutonic rocks.^[1]

References

↑ "Last "5" years paper". pakistan. Retrieved 25 May 2011.

Common igneous rocks classified by silicon dioxide content

Type	Ultramafic <45% SiO₂	Mafic 45–52% SiO₂	Intermediate 52–63% SiO₂	Intermediate–felsic 63–69% SiO₂	Felsic >69% SiO₂

Volcanic rocks: Subvolcanic rocks: Plutonic rocks:	Komatiite, Picrite basalt Kimberlite, Lamproite Peridotite	Basalt Diabase (Dolerite) Gabbro	Andesite Diorite	Dacite Granodiorite	Rhyolite Aplite—Pegmatite Granite

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