A lava type comprised primarily of magnesium (ma) and iron (fe) usually found at the mid-ocean ranges and hot spots. These yeail fluid lavas which retain very little gasses and generally do not erupt as violently.

is a rock type consisting of predominantly iron and magnesium silicate minerals with little quartz or feldspar minerals

A term applied to igneous rocks that are rich in ferromagnesian minerals or low in silica as basalt or gabbro.

It is a term used for describing the dark colored rocks or minerals which is composed of magnesium and iron.

Igneous rocks composed mostly of dark, iron- and magnesium-rich minerals.

An igneous rock composed chiefly of dark, ferromagnesium minerals.

An igneous rock composed primarily of one or more ferro-magnesian, dark minerals.

Adjective describing dark-colored minerals rich in iron and magnesium and relatively poor in silica (for example, pyroxene, amphibole, or olivine); also, describing rocks rich in mafic minerals.

A term used in reference to magmas or igneous rocks that are relatively poor in silica and rich in iron and magnesium.

ferromagnesian rich igneous rock (dark colored)

A term used to describe an igneous rock that has a large percentage of dark-colored minerals such as amphibole, pyroxene and olivine. Also used in reference to the magmas from which these rocks crystallize. Mafic rocks are generally rich in iron and magnesium. Basalt and gabbro are examples of mafic rocks. (See felsic to contrast.)

a mineral containing predominantly ferromagnesian rock forming silicates. In general, a dark mineral.

A mineral or rock rich in iron and magnesium silicates such as olivine and pyroxene.

refers to rocks or magmas that are formed largely of iron and magnesium silicates.

It is composed of one or more ferromagnesian (iron-magnesium), dark-colored minerals like olivine and pyroxene (in combination with quartz), feldspar or feldspathoid minerals.

A dark-coloured silicate mineral rich in iron and/or magnesium; ferromagnesium minerals, include olivine, pyroxene, amphibole and biotite. It is the opposite of silicic or felsic.

An igneous rock that is dark in colour, containing more than 50 percent ferromagnesium minerals, such as amphibole, pyroxene and olivine (e.g., basalt, gabbro).

a dark-colored igneous rock composed chiefly of ferromagnesian (magnes-ium-iron-rich) minerals, like augite, and gray-colored, calcium-rich plagioclase.

igneous rock with dark coloration due to high magnesium and iron content

A term used to describe minerals or igneous rocks that are rich in iron and/or magnesium. Mafic igneous rocks have a high percentage of dark-colored (mafic) minerals.

referring to a generally dark-coloured igneous rock with significant amounts of one or more ferromagnesian minerals, or to a magma with significant amounts of iron and magnesium.

Descriptive of igneous rocks composed dominantly of magnesium and iron rockforming silicates.

magnesium- and iron-rich igneous rock

Term used to describe the amount of dark-colored iron and magnesium minerals in an igneous rock. Complement of felsic.

An adjective used to describe a rock in which dark colored minerals predominates.

Said of an igneous rock composed chiefly of one or more ferromagnesian, dark-colored minerals in its mode; also, said of those minerals. The term was proposed by Cross, et al. to replace the term femag, which they did not consider to be euphonious. Etymol: a mnemonic term derived from ma gnesium + erric + ic. It is the complement of felsic.

An igneous rock composed chiefly of one or more dark colored ferromagnesian (iron-magnesium) minerals.

Refers to igneous rocks or magmas that are rich in minerals containing significant quantities of iron and magnesium; these rocks tend to contain lower concentrations of silica than silicic rocks, averaging around 45-50% silica.

consisting of or designating any of a group of dark minerals occurring in igneous rocks, composed chiefly of magnesium and iron. [AHDOS

Mafic refers to dark-colored igneous rock or magma that have significant amounts of iron and magnesium. For example, olivine, augite, and hypersthene are mafic rocks.

In geology, mafic minerals and rocks are silicate minerals, magmas, and volcanic and intrusive igneous rocks that have relatively high concentrations of the heavier elements. The term is a combination of "magnesium" and ferrum, the Latin word for iron [ma(gnesium) + f(errum) + ic] http://dictionary.reference.com/search?q=mafic. In spite of the name, mafic magmas also are rich in calcium and sodium.