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The most famous and destructive historical eruptions are mainly of this type. An eruptive phase can consist of a single eruption, or a sequence of several eruptions spread over several days, weeks or months. Explosive eruptions usually involve thick, highly viscous, silicic or felsic magma, high in volatiles like water vapor and carbon dioxide.
The 1815 Tambora eruption is the largest and most devastating observed eruption in recorded history; a comparison with other major eruptions is listed below. [ 4 ] [ 30 ] [ 37 ] The explosion was heard 2,600 kilometres (1,600 mi) or 3,350 kilometres (2,080 mi) away, and ash deposits were registered at a distance of at least 1,300 kilometres ...
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 richer in magnesium and iron. Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium ...
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 ...
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]
The Siberian Traps (Russian: Сибирские траппы, romanized: Sibirskiye trappy) are a large region of volcanic rock, known as a large igneous province, in Siberia, Russia. The massive eruptive event that formed the traps is one of the largest known volcanic events in the last 500 million years. The eruptions continued for roughly ...
The eruption that produced the Chaos Crags consisted of more than 90% mixed magma, [12] and likely resulted from the interaction of felsic and mafic magmas. [13] The Eagle Peak Sequence, which includes the Chaos Crags, consists of seven dacite and rhyodacite lava domes and lava flows, along with pyroclastic rock deposits. [11]
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]