Granodiorite
Encyclopedia : G : GR : GRA : Granodiorite
Granodiorite is an intrusive igneous rock similar to granite, but contains more plagioclase than potassium feldspar. It usually contains abundant biotite mica and hornblende, giving it a darker appearance than true granite. Mica may be present in well-formed hexagonal crystals, and hornblende may appear as needle-like crystals.
On average the upper continental crust has the same composition as granodiorite.
External link
- [Grandiorite definition at USGS] (public domain source)
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