It is one of the three main rock types, the others being sedimentary and metamorphic.
Volcanic Rocks. Volcanic rocks are also known as 'extrusive igneous rocks.' We see from their definition that volcanic rocks form on the surface, or 'exterior,' of the earth. If you remember that 'extrusive' and 'exterior' both start with the letters 'ext,' it may help you recall this term.  Igneous rock (derived from the Latin word ignis meaning fire) is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from partial melts of pre-existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Over 700 types of igneous rocks have been described, most of them having formed beneath the surface of Earth 's crust. adjective. A piece of igneous rock. A piece of igneous rock. The definition of igneous is something produced by volcanic action or intense fire. Rocks that have formed from solidified lava from a volcano are an example of rocks that would be described as igneous. igneous. 1  of, containing, or having the nature of, fire; fiery. 2  produced by the action of fire; specif., formed by volcanic action or intense heat, as intrusive or extrusive rock solidified from molten magma or lava. An Igneous rock is the product of cooled solidified magma/lava. As magma/lava cools it goes through the process of crystallization which turns it into an igneous rock. The amount of time it takes for an igneous rock to form depends on its location and its composition.  Full Definition of IGNEOUS. 1. : of, relating to, or resembling fire: fiery. 2. a: relating to, resulting from, or suggestive of the intrusion or extrusion of magma or volcanic activity. See igneous defined for English-language learners.  Igneous Rock Facts. Enjoy our igneous rock facts for kids. Find interesting information and a range of examples that help explain what igneous rocks are and what makes them different from other kinds of rocks. Igneous rock is formed when magma cools and solidifies, it may do this above or below the Earth's surface. Magma can be forced into rocks, blown out in volcanic explosions or forced to the surface as lava. The atoms and molecules of melted minerals are what make up magma.  The term for a rock formed when molten rock cools and hardens. Extrusive, or volcanic, igneous rock cools on the surface as lava. Intrusive igneous rock forms when molten rock cools underground. volcanic rock-extrusive igneous rock solidified near or on the surface of the Earth. porphyritic rock, porphyry-any igneous rock with crystals embedded in a finer groundmass of minerals. sodalite-a vitreous mineral consisting of sodium aluminum silicate and sodium chloride in crystalline form; occurs in igneous rocks. Definition of IGNEOUS ROCK. : rock formed by solidification of a molten magma — compare plutonic rock, volcanic rock. ADVERTISEMENT. This word doesn't usually appear in our free dictionary, but the definition from our premium Unabridged Dictionary is offered here on a limited basis. Note that some information is displayed differently in the Unabridged Intrusive igneous rocks are formed from magma that cools and solidifies within the crust of a planet, surrounded by pre-existing rock (called country rock); the magma cools slowly and, as a result, these rocks are coarse grained. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Over 700 types of igneous rocks have been described, most of them having formed beneath the surface of Earth 's crust. Noun. 1. igneous rock-rock formed by the solidification of molten magma. rock, stone-material consisting of the aggregate of minerals like those making up the Earth's crust; that mountain is solid rock; stone is abundant in New England and there are many quarries. volcanic rock-extrusive igneous rock solidified near or on the surface of the Earth. porphyritic rock, porphyry-any igneous rock with crystals embedded in a finer groundmass of minerals. sodalite-a vitreous mineral consisting of sodium aluminum silicate and sodium chloride in crystalline form; occurs in igneous rocks.
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what is igneous rock definition