Sideromelane

Sideromelane

Sideromelane is a vitreous basaltic volcanic glass, usually occurring in palagonite tuff, for which it is characteristic. It is a less common form of tachylite, with which it usually occurs together; however it lacks the iron oxide crystals dispersed in the glass, and therefore appearing transparent and pure, with yellow-brown color, instead of tachylite opaque black. It forms at higher temperatures and with more rapid chilling. Presence of sideromelane indicates higher temperature of the lava, and solidifying of the flow closer to the vent, probably by rapid quenching in a wet environment.

Sideromelane often forms during explosions of submarine volcanoes and subglacial volcanoes, and often occurs as fragments embedded in a palagonite matrix, forming hyaloclastite deposits. Sideromelane is a mafic rock.


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  • Sideromelane — Le sideromelane est un verre basaltique appelé verre volcanique, habituellement présent dans le tuf palagonite, pour lequel il est caractéristique. C est une forme moins commune de tachylite, avec lequel on le trouve habituellement ;… …   Wikipédia en Français

  • sideromelane — sid·er·o·mel·ane …   English syllables

  • sideromelane — ˌsidərəˈmeˌlān noun ( s) Etymology: German sideromelan, from sider + melan melane : obsidian …   Useful english dictionary

  • 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

  • Palagonite — is an alteration product from the interaction of water with volcanic glass of chemical composition similar to basalt. Palagonite can also result from the interaction between water and basalt melt. The water flashes to steam on contact with the… …   Wikipedia

  • Hyaloclastite — is a hydrated tuff like breccia rich in black volcanic glass, formed during volcanic eruptions under water or under ice. It has the appearance of angular flat fragments sized between a millimeter to few centimeters. The fragmentation occurs by… …   Wikipedia

  • Palagonite — Les plages de Moya, au nord est de Petite Terre à Mayotte, sont bordées de falaises à palagonite qui témoignent d un volcanisme qui s est manifesté à la surface de l océan …   Wikipédia en Français

  • Palagonites — Palagonite La palagonite est le produit de l altération provoquée par l interaction entre l eau et le verre volcanique à la composition proche du basalte. Formation et aspect La palagonite peut provenir de l interaction entre l eau et de la… …   Wikipédia en Français

  • Hyaloclastite — De la lave pahoehoe pénètre dans le Pacifique au Parc national des volcans d Hawaï Une hyaloclastite est une brèche ayant la consistance d un tuf, riche en morceaux de verre volcanique sombre, qui se forme lorsque des éruptions volcaniques se… …   Wikipédia en Français

  • Mafic — is an adjective describing a silicate mineral or rock that is rich in magnesium and iron; the term is a portmanteau of the words magnesium and ferric .[1] Most mafic minerals are dark in color and the relative density is greater than 3. Common… …   Wikipedia

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