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Plinian eruptions or Vesuvian eruptions are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in 79 AD, which destroyed the ancient Roman cities of Herculaneum and Pompeii. The eruption was described in a letter [1] written by Pliny the Younger, after the death of his uncle Pliny the Elder.
The 1980 eruption of Mount St. Helens in Washington, which ripped apart the volcano's summit, was a Plinian eruption of Volcanic Explosivity Index (VEI) 5. [3] The strongest types of eruptions, with a VEI of 8, are so-called "Ultra-Plinian" eruptions, such as the one at Lake Toba 74 thousand years ago, which put out 2800 times the material ...
Short title: Fig. 1-reg [Converted] Software used: Adobe Illustrator CS5: Date and time of digitizing: 01:49, 8 May 2013: File change date and time: 15:49, 8 May 2013
A.D. 79: Mount Vesuvius, Italy. Mount Vesuvius has erupted eight times in the last 17,000 years, most recently in 1944, but the big one was in A.D. 17. One of the most violent eruptions in history ...
On 13 December 1921, Cordón Caulle began a sub-plinian eruption, with a 6.2 km (4 mi) high plume, periodic explosions and seismicity. The eruption had a Volcanic Explosivity Index of 3 and ended in February 1922. In 1929 and 1934 the Cordón Caulle had fissure eruptions, both with an estimated Volcanic Explosivity Index of 2.
After the climactic eruption between 1.149 and 0.99 million years ago, about a dozen dike-fed eruptions produced rhyodacitic lava domes and lava flows inside the caldera. Another volcanic phase 1.1 to 0.5 million years ago emplaced over 60 andesite dikes, the eruptive products of which have since been stripped away by glacial erosion.
After an initial Plinian eruption produced an eruption column, [106] a vent in the southeastern part of the dome complex [107] produced the lower flow unit. Collapse of the first vent or the opening of a new one caused a break in the eruption; the layer between the units [105] and the downsag caldera formed at this time. [108]
The volcano was dormant for about half of last century, but rumbled back to life with a series of relatively small eruptions beginning in the 1990s. The government ordered evacuations then, and ...