When did Mount St. Helens Erupt?

Mount St. Helens eruption on May 18, 1980, was the most disastrous, greatest, deadliest, and economically destructive volcanic eruption ever recorded in North America.

A massive debris avalanche, triggered by a magnitude 5.1 earthquake, led to a lateral eruption that lowered the mountain’s peak elevation from 9,677 ft (2,950 m) to 8,363 ft (2,549 m), resulting in the formation of a 1 mile (1.6 km) wide horseshoe-shaped crater.

According to a United States Geological Survey (USGS) geologist, it completely destroyed an area of 230 square miles (595 square kilometers) in a matter of five (5) to nine (9) minutes. It essentially killed everything within that area.

Altogether, Fifty-seven (57) people and thousands of animals were killed, 200 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway were destroyed as a result of the May 1980 eruption of Mount St. Helens.

Until 2008, the volcano experienced uninterrupted volcanic activity following its 1980 eruption. The configuration of the lava domes requires greater pressure to erupt, thus geologists predict that upcoming eruptions will be more catastrophic. Nonetheless, Mount St. Helens is a well-liked hiking destination that is climbed all year round.


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