Gabbro

The classification scheme for gabbroic rocks without taking into account olivine and feldspathoids. Cpx is clinopyroxene, Opx is orthopyroxene, Plag is plagioclase. Rocks that contain less than 10% plagioclase are ultramafic (pyroxenite if pyroxenes are the dominant minerals). Pyroxene is almost exclusively clinopyroxene and norite is conversely rich in orthopyroxene. Anorthosite is almost monomineralic plagioclase-rock.
The classification scheme of olivine-bearing (>10%) gabbroic rocks. “Olivine” should be added to the rock name if it contains more than 10% of it. Gabbroic rock that contains almost no pyroxene is troctolite.

Work in progress

Coarse-grained igneous rock of basaltic composition that formed at depth and is 90% plagioclase. clinopyroxene,

Gabbro

     

   

 

 

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