Volcanic rocks
Volcanic Vol*can"ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster]

2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster]

3. Changed or affected by the heat of a volcano. [1913 Webster]

{Volcanic bomb}, a mass ejected from a volcano, often of molten lava having a rounded form.

{Volcanic cone}, a hill, conical in form, built up of cinders, tufa, or lava, during volcanic eruptions.

{Volcanic foci}, the subterranean centers of volcanic action; the points beneath volcanoes where the causes producing volcanic phenomena are most active.

{Volcanic glass}, the vitreous form of lava, produced by sudden cooling; obsidian. See {Obsidian}.

{Volcanic mud}, fetid, sulphurous mud discharged by a volcano.

{Volcanic rocks}, rocks which have been produced from the discharges of volcanic matter, as the various kinds of basalt, trachyte, scoria, obsidian, etc., whether compact, scoriaceous, or vitreous. [1913 Webster]


The Collaborative International Dictionary of English. 2000.

Look at other dictionaries:

  • volcanic rocks — plural noun Those formed by volcanic agency • • • Main Entry: ↑volcano …   Useful english dictionary

  • 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

  • Volcanic — Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3. Changed or …   The Collaborative International Dictionary of English

  • Volcanic bomb — Volcanic Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3.… …   The Collaborative International Dictionary of English

  • Volcanic cone — Volcanic Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3.… …   The Collaborative International Dictionary of English

  • Volcanic foci — Volcanic Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3.… …   The Collaborative International Dictionary of English

  • Volcanic glass — Volcanic Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3.… …   The Collaborative International Dictionary of English

  • Volcanic mud — Volcanic Vol*can ic, a. [Cf. F. volcanique, It. vulcanico.] 1. Of or pertaining to a volcano or volcanoes; as, volcanic heat. [1913 Webster] 2. Produced by a volcano, or, more generally, by igneous agencies; as, volcanic tufa. [1913 Webster] 3.… …   The Collaborative International Dictionary of English

  • Volcanic arc — Mariana Islands, an oceanic island arc A volcanic arc is a chain of volcanoes positioned in an arc shape as seen from above. Offshore volcanoes form islands, resulting in a volcanic island arc. Generally they result from the subduction of an… …   Wikipedia

  • Volcanic glass — A sand grain of volcanic glass under the petrographic microscope. Its amorphous nature makes it go extinct in cross polarized light (bottom frame). Scale box in millimeters. Volcanic glass is the amorphous (uncrystallized) product of rapidly… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”