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[1], [3] The composition of silica within basaltic magma ranges from 45-55 weight percent (wt.%), or mass fraction of a species. [1] It forms in temperatures ranging from approximately 1830 °F to 2200 °F. [1], [3] Basaltic magma has the lowest viscosity and volatiles content, yet still may be up to 100,000 times more viscous than water. [1]
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.
The Grímsvötn volcano in Iceland is a sub-glacial volcano, located beneath the Vatnajökull ice cap. For a typical sub-glacial eruption, overlying glacial ice is melted by the heat of the volcano below, and the subsequent introduction of meltwater to the volcanic system results in a phreatomagmatic explosion. [ 12 ]
Vulcanian eruptions display several common characteristics. The mass of rock ejected during the eruption is usually between 10 2 and 10 6 tonnes [1] and contains a high proportion of non-juvenile material (> 50%). During active periods of volcanic activity, intervals between explosions vary from less than 1 minute (e.g. Anak Krakatoa) to about ...
Volcanic rocks are named according to both their chemical composition and texture. Basalt is a very common volcanic rock with low silica content. 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.
A volcanic eruption is essentially the only natural way for short-lived – less than a few years – gases like sulfur dioxide and water vapor to make it into the stratosphere.
This figure describes the geological aspects and processes of the carbonate silicate cycle, within the long-term carbon cycle. The carbonate–silicate geochemical cycle, also known as the inorganic carbon cycle, describes the long-term transformation of silicate rocks to carbonate rocks by weathering and sedimentation, and the transformation of carbonate rocks back into silicate rocks by ...
Basaltic volcanic glass is also present in pillow lavas. [6] Of the cooling mechanisms responsible for forming volcanic glass, the most effective is quenching by water, followed by cooling by entrained air in an eruption column. The least effective mechanism is cooling at the bottom of a flow in contact with the ground. [4]