ultramafic

American  

[uhl-truh-maf-ik] / ˌʌl trəˈmæf ɪk /

adjective

Geology.

1. ultrabasic.

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ultramafic Scientific  

/ ŭl′trə-măf′ĭk /

1. Containing mainly mafic minerals. Used of igneous rocks and often used interchangeably with ultrabasic. Dunite is an ultramafic rock.

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Etymology

Origin of ultramafic

First recorded in 1940–45; ultra- + mafic

Example Sentences

See Examples For:

ultramafic

Start with ultramafic wastes, the calcium- and magnesium-rich rock in which diamonds, along with metals such as nickel, platinum, and palladium are found.

From Science Magazine ● Sep. 3, 2020

If magma at composition A is ultramafic, as the magma cools it changes composition as different minerals crystallize from the melt and settle to the bottom of the magma chamber.

From Textbooks ● Jan. 1, 2017

In the figure, the righthand column lists the four groups of igneous rock from top to bottom: ultramafic, mafic, intermediate, and felsic.

From Textbooks ● Jan. 1, 2017

As has already been described, igneous rocks are classified into four categories, based on either their chemistry or their mineral composition: felsic, intermediate, mafic, and ultramafic.

From Textbooks ● Jan. 1, 2015

Explain why ultramafic intrusions, like those of the Muskox Intrusion, are relatively common in Archean rocks, but rare in Phanerozoic rocks.

From Textbooks ● Jan. 1, 2015