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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 ...
In the interval between 7,000 and 5,000 years ago Puyehue had rhyolitic eruptions that produced lava domes. The lava domes were later destroyed after a sequence of strong eruptions that were part of an explosive eruptive cycle. These last eruptions were likely of phreatomagmatic and sub-plinian type and occurred around 1,100 years ago (~850 CE ...
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 ...
The first of these, a Plinian eruption, [91] also deposited tephra in Laguna Salinas, north of Huaynaputina, and produced a block-and-ash flow to its south. [86] A debris avalanche deposit crops out on the eastern side of the Río Tambo, opposite to the amphitheatre; [30] it may have been formed not long before the 1600 eruption. [86]
The eruption ejected about 13–47 cubic kilometres [5] [6] [7] of magma (dense rock equivalent) and formed a caldera, which now contains a lake (Heaven Lake). The eruption had two phases that each included a Plinian fallout and a pyroclastic flow and erupted magmas that were different in composition. [8]
The entire Plinian eruption lasted about 20 hours and emitted 7.8 km 3 (1.9 cu mi) of magma. [26] Another attempt at reconstruction by numerical simulation shows a different Plinian process. The eruptive column rose to 44 km (27 mi), and the entire phase was completed within 4 hours with a magma volume of 23 km 3 (5.5 cu mi).
The volcano usually generates Vulcanian to Plinian eruptions, which produce swift-moving currents of hot gas and rock called pyroclastic flows. These eruptions often cause massive lahars (mud and debris flows), which pose a threat to human life and the environment. The impact of such an eruption is increased as the hot gas and lava melt the ...