In igneous petrology, an intermediate composition refers to the chemical composition of a rock that has 51.5–63 wt% SiO2 being an intermediate between felsic and mafic compositions.
Typical intermediate rocks include andesite and trachyandesite among volcanic rocks and diorite and granodiorite among plutonic rocks.
Volcanic rocks:Subvolcanic rocks:Plutonic rocks: Picrite basaltPeridotite BasaltDiabase (Dolerite)Gabbro AndesiteMicrodioriteDiorite DaciteMicrogranodioriteGranodiorite RhyoliteMicrograniteGranite
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