intermediate rock
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Intermediate rocks are a classification of igneous rocks based on their silica content, falling between felsic and mafic rocks. They typically contain between 55% and 65% silica. Examples of intermediate rocks include syenite, diorite, and monzonite, with an average silica content of around 59%.12
Magma types are also classified by their silica content and temperature. Andesitic magma is considered intermediate, with temperatures ranging from 800–1,000 °C (about 1,470–1,830 °F) and a silica content that aligns with intermediate rocks. The silica content influences the minerals that crystallize from magma as it cools, affecting the final composition and properties of the rock.312
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- felsic and mafic rocks
…and 65 percent silica are intermediate; those with between 45 and 55 percent silica are mafic; and those with less than 45 percent are ultramafic. Compilations of many rock analyses show that rhyolite and granite are felsic, with an average silica content of about 72 percent; syenite, diorite, and monzonite…
Read More…and 65 percent silica are intermediate; those with between 45 and 55 percent silica are mafic; and those with less than 45 percent are ultramafic. Compilations of many rock analyses show that rhyolite and granite are felsic, with an average silica content of about 72 percent; syenite, diorite, and monzonite…
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igneous rockChemical components…more than 66 percent silica; intermediate, rocks with 55 to 66 percent silica; and subsilicic, rocks containing less than 55 percent silica. The latter may be further divided into two groups: mafic, rocks with 45 to 55 percent silica and ultramafic, those containing less than 45 percent. The subsilicic rocks,…
Read More…more than 66 percent silica; intermediate, rocks with 55 to 66 percent silica; and subsilicic, rocks containing less than 55 percent silica. The latter may be further divided into two groups: mafic, rocks with 45 to 55 percent silica and ultramafic, those containing less than 45 percent. The subsilicic rocks,…
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