mafic rock — A general term for igneous rock composed chiefly of one or more ferromagnesian, dark colored minerals; also said of those minerals. Compare: felsic rock. GG … Glossary of landform and geologic terms
Mafic — is an adjective describing a silicate mineral or rock that is rich in magnesium and iron; the term is a portmanteau of the words magnesium and ferric .[1] Most mafic minerals are dark in color and the relative density is greater than 3. Common… … Wikipedia
rock — rock1 rockless, adj. rocklike, adj. /rok/, n. 1. a large mass of stone forming a hill, cliff, promontory, or the like. 2. Geol. a. mineral matter of variable composition, consolidated or unconsolidated, assembled in masses or considerable… … Universalium
Rock — /rok/, n. a male given name. * * * I In geology, a naturally occurring and coherent aggregate of minerals. The three major classes of rock igneous, sedimentary, and metamorphic are based on the processes that formed them. These three classes are… … Universalium
Rock cycle — rocks do not remain in equilibrium and are forced to change as they encounter new environments. The rock cycle is an illustration that explains how the 3 rock types are related to each other and how processes change from one type to another over… … Wikipedia
mafic — /ˈmæfɪk/ (say mafik) adjective of some igneous rocks and their constituent minerals, composed dominantly of the magnesium rock forming silicates. Compare felsic …
igneous rock — Any of various crystalline or glassy, noncrystalline rocks formed by the cooling and solidification of molten earth material (magma). Igneous rocks comprise one of the three principal classes of rocks, the others being metamorphic and sedimentary … Universalium
metamorphic rock — Any of a class of rocks that result from the alteration of preexisting rocks in response to changing geological conditions, including variations in temperature, pressure, and mechanical stress. The preexisting rocks may be igneous, sedimentary,… … Universalium
Igneous rock — Geologic provinces of the world (USGS) Shield … Wikipedia
felsic and mafic rocks — ▪ igneous rock division of igneous rocks (mafic rock) on the basis of their silica content. Chemical analyses of the most abundant components in rocks usually are presented as oxides (oxide) of the elements; igneous rocks typically consist… … Universalium
