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Related to andesite: Andesite line


A gray, fine-grained volcanic rock consisting chiefly of plagioclase feldspar and one or more mafic minerals.

[After the Andes.]


(ˈændɪˌzaɪt) or


(Geological Science) a fine-grained tan or grey volcanic rock consisting of plagioclase feldspar, esp andesine, amphibole, and pyroxene
[C19: from Andes + -ite1]


(ˈæn dəˌzaɪt)

a dark volcanic rock composed essentially of plagioclase feldspar and one or more mafic minerals.
[1840–50; after the Andes; see -ite1]
an`de•sit′ic (-ˈzɪt ɪk) adj.


A dark, fine-grained rock, taking its name from the Andes Mountains.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.andesite - a dark grey volcanic rockandesite - a dark grey volcanic rock    
igneous rock - rock formed by the solidification of molten magma
References in periodicals archive ?
A comparison of average calc-alkaline andesite from Plio- Pleistocene volcanics of the Chagai arc with its counterparts in some famous continental margin and oceanic island arcs of the world show relatively more resemblance in LILE, HFSE and REE with Zagros, less with Japan and Sunda arcs, and least with its counterpart in the Andes arc.
This zone consists of highly tectonically fractured andesite which has been altered by hydrothermal activity.
The andesite rock in the Cheviot area formed 395-370 million years ago.
The axe, which is made of andesite - a type of volcanic rock - would have been used by our ancestors for butchering animals and is only the ninth such tool found in the Midlands in more than a century of investigation.
Les Fyffe provides a new interpretation of stratigraphy in the Eel River area of west-central New Brunswick, and shows that volcanic rocks in the area include andesite and likely formed in an arc environment.
Photo: Andesite spire marks approach to North Butte summit for hikers on guided outing Day-hikes usually last from early morning until near sunset.
Argillic altered andesite with oxides, carbonates and local galena
low-silica andesite in the lower part of the Porten Road Formation is highly enriched in LREE and LFSE.
In addition to gold occurring in the quartz veins, it also occurs in adjacent rock units (the andesite dyke, fault gouge and fresh granodiorite.
Among the chemically similar andesite samples, those with higher MgO also contain higher amounts of incompatible elements.
The two veins are separated by a sheared andesite dyke that is generally 40cm in width.
The alluvial deposits on Dime Creek are composed of mostly volcanic andesite and basalt sand and gravel with occasional cobbles of intrusive olivine dunite.