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A fine-grained extrusive volcanic rock, similar to granite in composition and usually exhibiting flow lines.

[Greek rhuāx, stream (from rhein, to flow; see sreu- in Indo-European roots) + -lite.]


(Geological Science) a fine-grained igneous rock consisting of quartz, feldspars, and mica or amphibole. It is the volcanic equivalent of granite
[C19: rhyo- from Greek rhuax a stream of lava + lite]
rhyolitic adj


(ˈraɪ əˌlaɪt)

a fine-grained igneous rock rich in silica: the volcanic equivalent of granite.
[1865–70; rhyo- (irreg. < Greek rhýax stream of lava) + -lite]
rhy`o•lit′ic (-ˈlɪt ɪk) adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rhyolite - very acid volcanic rockrhyolite - very acid volcanic rock    
igneous rock - rock formed by the solidification of molten magma
References in periodicals archive ?
This quartz vein is hosted within a highly sericitized and sheared rhyolite unit of about 5 to 10m thick that corresponds very well with a similar altered rhyolite unit intersected in previously drilled and reported hole PE-2013-04 where visible gold within some quartz veining was also noted and values of up to 12.
In fact, Karen was looking at a well-known rock outcrop of rhyolite (a very ancient rock located in north Pembrokeshire) known as "the lion and the unicorn".
In the southeastern part, the granite is invaded by parallel sheets and swarms of many mafic dykes, and rhyolite sheets.
The nine contributions that make up the main body of the text are devoted to the Pleistocene megaflood landscapes of the Channeled Scabland, basalt and rhyolite volcanism in the western Snake River Plain of Idaho, the Columbia River Basalt Group of western Idaho and eastern Washington, and many other related subjects.
Rocks consist of Palaeozoic dolomite/limestone detachment blocks surrounded and underlain by Tertiary rhyolite tuffs.
The active nonhuman materials in the landscape--lively sandstone and vital rhyolite, sky and light--saturated my body's passive movement and inert gaze.
The main volcanic lithologies are predominately rhyolite, dacite and andesite of Eocene to Miocene in age.
The Round Top project is based on a Tertiary rhyolite intrusion that is enriched in both heavy and light rare earth elements (REEs).
Baragiola, a professor of engineering physics in the University of Virginia School of Engineering and Applied Science set up experiments to measure ozone produced by crushing or drilling into different igneous and metamorphic rocks, including granite, basalt, gneiss, rhyolite and quartz.
Extensive mineralized system controlled by NE and NW structures, favourable host rocks and subsurface rhyolite domes
These holes targeted the untested core of the Calandria Norte rhyolite dome with coincident anomalous chargeability, at a level below the somewhat disappointing 2009 drill intersections.
335 Ma Cumberland Hill Formation of southern New Brunswick consist of peralkaline rhyolite and trachyte.