Glossary of volcanic terms. - University of Wisconsin Oshkosh. G. J. Hudak. 2001.
Tuff — (from the Italian tufo ) is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff should not be confused with tufa , another type of rock. Volcanic ashThe products of a volcanic eruption are… … Wikipedia
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
Basalt — For the World War II raid, see Operation Basalt. For the cities, see Basalt, Colorado and Basalt, Idaho. Basalt Igneous Rock Composition … Wikipedia
Lava — flow redirects here. For the programming anti pattern, see Lava flow (programming). For other uses, see Lava (disambiguation) … Wikipedia
Volcanic rock — is an igneous rock of volcanic origin. Texture Volcanic rocks are usually fine grained or aphanitic to glassy in texture. They often contain clasts of other rocks and phenocrysts. Phenocrysts are crystals that are larger than the matrix and are… … Wikipedia
Tachylite — (also spelled tachylyte) is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt. It is a basic type of igneous rock that is decomposable by acids and readily fusible. The color is a… … Wikipedia
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
Extrusive — refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. This is opposed to… … Wikipedia
Leucite — is a rock forming mineral composed of potassium and aluminium tectosilicate K [AlSi2O6] . Crystals have the form of cubic icositetrahedra but, as first observed by Sir David Brewster in 1821, they are not optically isotropic, and are therefore… … Wikipedia
Felsic — is a term used in geology to refer to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. The term combines the words feldspar and silica. Felsic minerals are… … Wikipedia
