Meager volcan éruptions
volcan complexe 2680 m / 8,793 ft
Canada, 50.63°N / -123.5°W
Liste des éruptions: 410 BC ± 200 years (radiocarbon dated)
The eruption began with a Plinian phase producing an eruption column of at least 20 km height. Its deposit, pumice and ash fall, is known as the Bridge River Ash, and can be found as far as as Alberta, 530 km from the volcano. Pyroclastic flows deposited ignimbrites (welded ash flow tuffs).
The Plinian phase was followed by a less explosive phase producing block and ash flow deposits that accumulated mainly in the Lillooet River valley. The vent of the eruption is located at 1500 m elevation on northeastern shoulder of Plinth Peak, 1000 m above the floor of Lillooet Valley.
This eruption was similar in character to the 1980 eruption of Mount St. Helens
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