What is peridotite rock?

Peridotite is the general name for the ultrabasic or ultramafic intrusive rocks, dark green to black in color, dense and coarse-grained texture, often as layered igneous complex.

How is peridotite rock formed?

Peridotite is derived from Earth’s mantle, either as solid blocks and fragments, or as crystals accumulated from magmas that formed in the mantle. The compositions of peridotites from these layered igneous complexes vary widely, reflecting the relative proportions of pyroxenes, chromite, plagioclase, and amphibole.

What is the importance of peridotite rock?

Peridotites are economically important rocks because they often contain chromite – the only ore of chromium; they can be source rocks for diamonds; and, they have the potential to be used as a material for sequestering carbon dioxide. Much of Earth’s mantle is believed to be composed of peridotite.

What is characteristics of peridotite?

Peridotite is a very dense, coarse-grained, olivine-rich, ultra- mafic intrusive rock. It is noted for its low silica content, and contains very little or no feldspar ( orthoclase, plagioclase). It is a common component of oceanic lithosphere, and is derived from the upper mantle.

What is the density of peridotite?

between 3.2 – 3.4 g/cm3
Peridotite and Dunite are more dense than crustal rocks (with average densities between 3.2 – 3.4 g/cm3).

What is composed of peridotite?

Peridotite is a dark-colored igneous rock consisting mostly of olivine and pyroxene. It is an important rock type because the Earth’s mantle is predominantly composed of it. A classification diagram of ultramafic rocks.

What is the crystal size of peridotite?

The large grains are about 4 mm long parallel to the mineral lineation and 2 mm wide, perpendicular to the foliation. The small olivine grains are equant and less than 100 μm in diameter, most are less than 10 μm.

What is fertile peridotite?

lherzolite – This is a type of peridotite that consists chiefly of olivine but which also contains pyroxene and Al-bearing phases such as plagioclase, Al-spinel, or Al-garnet. Lherzolites are considered to be “fertile” mantle rocks because they can produce basaltic magmas during partial melting.

Is peridotite fast or slow cooling?

Peridotites of the Iwanaidake ophiolite have steep slopes, almost along constant cooling rate curves; Finero peridotites show gentle slopes, indicative of a rapid increase in cooling rate conditions between ~850 and ~650 °C.