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  2. Pneumonoultramicroscopicsilicovolcanoconiosis - Wikipedia

    en.wikipedia.org/wiki/Pneumonoultramicroscopicsi...

    volcano: from Latin, referring to volcano; coni: from ancient Greek (κόνις, kónis) which means dust-osis: from ancient Greek, suffix to indicate a medical condition; This word was invented at a meeting of the National Puzzlers' League (N.P.L.) by its president Everett M. Smith.

  3. Rhyolite - Wikipedia

    en.wikipedia.org/wiki/Rhyolite

    Its high silica content makes rhyolitic magma extremely viscous. This favors explosive eruptions over effusive eruptions, so this type of magma is more often erupted as pyroclastic rock than as lava flows. Rhyolitic ash-flow tuffs are among the most voluminous of continental igneous rock formations.

  4. Volcanic rock - Wikipedia

    en.wikipedia.org/wiki/Volcanic_rock

    Rhyolite is a volcanic rock with high silica content. Rhyolite has silica content similar to that of granite while basalt is compositionally equal to gabbro. Intermediate volcanic rocks include andesite, dacite, trachyte, and latite. [citation needed] Pyroclastic rocks are the product of explosive volcanism. They are often felsic (high in

  5. Volcano - Wikipedia

    en.wikipedia.org/wiki/Volcano

    Augustine Volcano (Alaska) during its eruptive phase on January 24, 2006. A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.

  6. Silicification - Wikipedia

    en.wikipedia.org/wiki/Silicification

    Lithological silica are brought to surface through volcanic events whereas weathering of pre-existing rocks releases silica into the waters. The sources of silica can be divided into two categories: silica in organic and inorganic materials. The former category is also known as biogenic silica, which is a ubiquitous material in animals and plants.

  7. Volcanic ash - Wikipedia

    en.wikipedia.org/wiki/Volcanic_ash

    The types of minerals present in volcanic ash are dependent on the chemistry of the magma from which it erupted. Considering that the most abundant elements found in silicate magma are silicon and oxygen, the various types of magma (and therefore ash) produced during volcanic eruptions are most commonly explained in terms of their silica content.

  8. Extrusive rock - Wikipedia

    en.wikipedia.org/wiki/Extrusive_rock

    Shield volcanoes are large, slow forming volcanoes [6] that erupt fluid basaltic magma that cools to form the extrusive rock basalt. Basalt is composed of minerals readily available in the planet's crust, including feldspars and pyroxenes. [2] Fissure volcanoes pour out low viscosity basaltic magma from fissure vents to form the extrusive rock ...

  9. Silicon dioxide - Wikipedia

    en.wikipedia.org/wiki/Silicon_dioxide

    Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO 2, commonly found in nature as quartz. [5] [6] In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a