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List of largest volcanic eruptions. The 1991 eruption of Mount Pinatubo, the largest eruption since 1912, is dwarfed by the eruptions in this list. In a volcanic eruption, lava, volcanic bombs, ash, and various gases are expelled from a volcanic vent and fissure. While many eruptions only pose dangers to the immediately surrounding area, Earth ...
Felsic. In geology, felsic is a modifier describing igneous rocks that are relatively rich in elements that form feldspar and quartz. [1] It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen ...
Paraná and Etendeka traps, Brazil, Namibia and Angola form 128 to 138 million years ago. 132 million years ago, a possible supervolcanic eruption occurred, ejecting 8,600 cubic kilometers (2,063 cu mi). [90] Formation of the Karoo-Ferrar flood basalts begins 183 million years ago.
The 1815 Tambora eruption is the largest and most devastating observed eruption in recorded history; a comparison with other major eruptions is listed below. [ 3 ] [ 29 ] [ 36 ] The explosion was heard 2,600 kilometres (1,600 mi) away, and ash deposits were registered at a distance of at least 1,300 kilometres (810 mi).
From the 1631 eruption until 1944, there was a comparatively small eruption every few years, emitting 0.001–0.01 km 3 of magma. For Vesuvius, the amount of magma expelled in an eruption increases roughly linearly with the interval since the previous one, and at a rate of around 0.001 cubic kilometres (0.00024 cu mi) for each year. [75]
A volcano is a rupture 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. The process that forms volcanoes is called volcanism. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth ...
Felsic eruption forms felsic volcanic rocks near the volcano and a spectrum of volcano-sedimentary sequence in the sea in Archean. [1] Archean felsic volcanic rocks are felsic volcanic rocks that were formed in the Archean Eon (4 to 2.5 billion years ago). [2] The term "felsic" means that the rocks have silica content of 62–78%. [3]
Eruptions can last anywhere from hours to days, with longer eruptions being associated with more felsic volcanoes. Although they are usually associated with felsic magma, Plinian eruptions can occur at basaltic volcanoes, if the magma chamber differentiates with upper portions rich in silicon dioxide, [40] or if magma ascends rapidly. [42]