ultramaficrock
Ultramafic rock is a category of igneous rocks characterized by very low silica content and high magnesium and iron. The mineral assemblage is dominated by dark ferromagnesian minerals, chiefly olivine and pyroxene, with feldspar and quartz present only in trace amounts. Because of their composition, ultramafic rocks are among the most Mg- and Fe-rich rocks known.
Common ultramafic rock types include peridotite (which subdivides into dunite, harzburgite, and lherzolite) and pyroxenite. Ultramafic
Most ultramafic rocks originate in the Earth's mantle, formed by partial melting and crystallization at high
Outcrops are rare at the surface but are found in ophiolites, deeply exhumed mantle sections, and as
Weathering and alteration of ultramafic rocks commonly lead to serpentinization, producing serpentinite and secondary minerals such