- Plinian eruption
Plinian eruptions are
volcanic eruptions marked by their similarity to the eruption of Mt. Vesuvius in AD 79 (as described in a letter written by Pliny the Younger) that killed Pliny the Elder.
Plinian eruptions are marked by columns of smoke and ash extending high into the
stratosphere. The key characteristics are ejection of large amount of pumiceand very powerful continuous gas blast eruptions.
Short eruptions can end in less than a day. Longer events can take several days to months. The longer eruptions begin with production of clouds of
volcanic ash, optionally with pyroclastic flows. The amount of magma erupted can be so large that the top of the volcano may collapse, resulting in a caldera. Fine ash can deposit over large areas. Plinian eruptions are often accompanied by loud noises, such as heard at Krakatoa.
The examples of large Plinian eruptions resulting in formation of a caldera are the 1883
Krakatoaeruption in Indonesia, the 1980 eruption of Mount St. Helens, the 1815 eruption of Mount Tambora, also in Indonesia, the 1667 & 1739 eruptions of Mount Tarumaein Japan[ Enlightenment activities for improvement on disasters from Tarumae Volcano, Japan, Cities on Volcanoes 4, 23-27 January 2006 ] , the 1600 BC Thera eruption, and the 4860 BC eruption that formed the Crater Lake, and of course Vesuviusin AD 79, which was the prototypical Plinian Eruption. The lava is usually rhyolitic and rich on silicates; basalticlavas are unusual for Plinian eruptions, the example is the 1886 eruption of Mount Tarawera.
He described his uncle's involvement from the first observation of the eruption:
::On the 24th of August, about one in the afternoon, my mother desired him to observe a cloud which appeared of a very unusual size and shape. He had just taken a turn in the sun and, after bathing himself in cold water, and making a light luncheon, gone back to his books: he immediately arose and went out upon a rising ground from whence he might get a better sight of this very uncommon appearance. A cloud, from which mountain was uncertain, at this distance (but it was found afterwards to come from Mount Vesuvius), was ascending, the appearance of which I cannot give you a more exact description of than by likening it to that of a pine tree, for it shot up to a great height in the form of a very tall trunk, which spread itself out at the top into a sort of branches; occasioned, I imagine, either by a sudden gust of air that impelled it, the force of which decreased as it advanced upwards, or the cloud itself being pressed back again by its own weight, expanded in the manner I have mentioned; it appeared sometimes bright and sometimes dark and spotted, according as it was either more or less impregnated with earth and cinders. This phenomenon seemed to a man of such learning and research as my uncle extraordinary and worth further looking into. "(Sixth Book of Letters, Letter 16.)"
Pliny the Elder set out to rescue the victims from their perilous position on the shore of the
Bay of Naples, and launched his galleys, crossing the bay to Stabiae(near the modern town of Castellammare di Stabia). Pliny the Younger provided an account of his death, and suggested that he collapsed and died through inhaling poisonous gases emitted from the volcano. His body was found interred under the ashes of the Vesuvius with no apparent injuries on 26 August, after the plume had dispersed, confirming asphyxiation or poisoning.
Types of volcanic eruptions
Pliny the Elder
Pliny the Younger
* [http://volcanoes.usgs.gov/Products/Pglossary/PlinianEruption.html USGS Photo Glossary Entry for Plinian Eruptions]
Wikimedia Foundation. 2010.
Look at other dictionaries:
plinian eruption — ALASKA VOLCANO OBSERVATORY GLOSSARY An explosive eruption in which a steady, turbulent stream of fragmented magma and magmatic gases is released at a high velocity from a vent. Large volumes of tephra and tall eruption columns are characteristic … Glossary of volcanic terms
Plinian eruption — noun a volcanic eruption in which a stream of gas and ash is violently ejected to a height of several miles • Hypernyms: ↑volcanic eruption, ↑eruption … Useful english dictionary
Eruption column — over Mount Pinatubo in the Philippines An eruption column consists of hot volcanic ash emitted during an explosive volcanic eruption. The ash forms a column rising many kilometres into the air above the peak of the volcano. In the most explosive… … Wikipedia
eruption — noun 1. the sudden occurrence of a violent discharge of steam and volcanic material (Freq. 1) • Syn: ↑volcanic eruption • Derivationally related forms: ↑erupt • Hypernyms: ↑discharge • … Useful english dictionary
Plinian — [ plɪnɪən] adjective Geology relating to or denoting a type of volcanic eruption in which a narrow stream of gas and ash is violently ejected from a vent to a height of several miles. Origin C17: from Ital. pliniano, with ref. to the eruption of… … English new terms dictionary
Phreatomagmatic eruption — Phreatomagmatic eruptions are defined as juvenile forming eruptions as a result of interaction between water and magma. They are different from magmatic and phreatic eruptions. The products of phreatomagmatic eruptions contain juvenile clasts,… … Wikipedia
Hatepe eruption — The Hatepe eruption (named for the Hatepe Plinian pumice fall deposit [cite journal |last=Talbot |first=J. P. |authorlink= |coauthors=Self, S.; Wilson, C. J. N. |year=1994 |month= |title=Dilute gravity current and rain flushed ash deposits in the … Wikipedia
Minoan eruption — Satellite image of Thera, November 21, 2000 Volcano Thera Date 2nd millennium BCE Type … Wikipedia
Phreatic eruption — A Phreatic eruption, also called an ultravulcanian eruption, occurs when rising magma makes contact with ground or surface water. The extreme temperature of the magma (anywhere from 600 °C to 1,170 °C (1110–2140 °F)) causes near instantaneous… … Wikipedia
phreatic eruption — ALASKA VOLCANO OBSERVATORY GLOSSARY An explosive volcanic eruption caused when water and heated volcanic rocks interact to produce a violent expulsion of steam and pulverized rocks. Magma is not involved. GLOSSARY OF VOLCANIC TERMS A steam… … Glossary of volcanic terms