from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A fine-grained extrusive volcanic rock, similar to granite in composition and usually exhibiting flow lines.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An igneous, volcanic (extrusive) rock, of felsic composition, with aphanitic to porphyritic texture.
from the GNU version of the Collaborative International Dictionary of English
- n. A quartzose trachyte, an igneous rock often showing a fluidal structure.
from The Century Dictionary and Cyclopedia
- n. The name given by Richthofen to certain rocks occurring in Hungary which resemble trachyte, but are distinguished from it by the presence of quartz as an essential ingredient, and also by a great variety of texture, showing more distinctly than rocks usually do that the material had flowed while in a viscous state.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. very acid volcanic rock
Left long enough, this magma erupts as a substance known as rhyolite - a very pale yellow or grey rock which is responsible for the beautiful colours in Landmannalaugar and Yellowstone in the US.
Field work has been focused to define a drilling program to test the gold mineralization present in a silicified dacite dike (previously classified as a rhyolite dike), which outcrops extensively on the concessions.
The first is that, in addition to the basaltic magma associated with mid-ocean ridges, Iceland's volcanoes produce significant amounts of rhyolite, which is silica-rich and, more significantly, contains a lot more volatile substances.
Planting directly into more silicic ash such as rhyolite is however more problematic, due to nutrient issues such as nitrogen and calcium deficiency (Neild and others, 1998).
Planting directly into more silicic ash such as rhyolite is however more problematic, due to nutrient issues such as nitrogen and calcium deficiency (Neild and others,
The National Geographic theory is summarized by Tony Burton and visualizes the balls forming by crystallization of hot ash around nuclei of lava fragments, producing boulders of rhyolite.
The reason I wanted to see this beach is because the book said that if, conditions were right, the sound of the waves hitting this unique shoreline of flat, shingle-like “pink rhyolite and felsite bedrock” makes a tinkling, bell-like sound.
Element redistribution during hydrothermal alteration of rhyolite in an active geothermal system; Yellowstone drill cores Y-7 and Y-8: Geochimica et
Many of the pieces he excavated are of a rock called rhyolite.
Dacite and rhyolite magmas with low concentrations of dissolved gases can erupt as lava flows, producing little or no ash.