Pyroclastic rocks or pyroclastics (derived from the links=no, meaning fire; and κλαστός, meaning broken) are clastic rocks composed solely or primarily of volcanic materials. Where the volcanic material has been transported and reworked through mechanical action, such as by wind or water, these rocks are termed volcaniclastic. Commonly asso...
Found on
http://en.wikipedia.org/wiki/Pyroclastic_rock
(from the article `igneous rock`) ...and dislocation of solid material. In volcanic environments they generally result from explosive activity or the incorporation of solid fragments ... ...millimetre). The latter includes silt and clay, which both have a size indistinguishable by the human eye and are also termed dust. Most shales ... ...
Found on
http://www.britannica.com/eb/a-z/p/137
A rock formed when small particles of magma are blown from the vent of a volcano by escaping gas.
Found on
http://www.encyclo.co.uk/local/22392
A rock formed by the accumulation of fragments of volcanic rock scattered by volcanic explosions.
Found on
http://www.scientificpsychic.com/etc/geology-glossary.html
(Gk: pyr=fire; klastos broken in pieces) fragments of volcanic material blown into the air during an explosion. Some are thrown out of the volcano as solid fragments (rocks); others (e.g. pumice, scoria) are made from liquid globules, which have solidified in the air and landed on Earth as solids.
Found on
http://www.seafriends.org.nz/books/glossary.htm
consolidated volcanic fragments that have been extruded explosively and deposited by settling (like sediment) either on land or in water.
Found on
https://www.encyclo.co.uk/local/20132
No exact match found.
