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How fast was the Mt St Helens landslide?

How fast was the Mt St Helens landslide?

1,072 km/hr
This blast, traveling at speeds of up to 1,072 km/hr (670 mi/hr), quickly overtook the landslide and extended to up to 30.4 km (19 mi) from the volcano.

How many hours did Mt St Helens erupt?

9 hours
During the 9 hours of vigorous eruptive activity on May 18, 1980, about 540 million tons of ash from Mount St. Helens fell over an area of more than 22,000 square miles (57,000 square kilometers).

How long did it take for the ash from Mt St Helens travel?

Some of the ash drifted around the globe within about 2 weeks. Learn more: Ash and Tephra Fall Hazards at Mount St. Helens.

What was unusual about the Mt St Helens eruption?

Mount St. Helens’ volcanic cone was completely blasted away and replaced by a horseshoe-shaped crater–the mountain lost 1,700 feet from the eruption. The volcano produced five smaller explosive eruptions during the summer and fall of 1980 and remains active today.

What was the biggest landslide ever?

the Mount St. Helens
Helens massive Eruption: The largest landslide ever recorded. In 1980, the explosion of Mount St. Helens in the state of Washington, United States, triggered the largest (on land) landslide ever recorded.

How many died from Mt St Helens?

57 people
It was shortly after 8:30 a.m. on May 18, 1980 when Mount St. Helens erupted in Washington state. The eruption would quickly become the deadliest in U.S. history, killing 57 people.

What is the most deadliest landslide?

The worst landslide in U.S. history was in 1928, when as many as 500 people were killed after the collapse of the St. Francis Dam near Los Angeles, according to geologist Lynn Highland of the U.S.Geological Survey.

Which are the most unsafe houses in landslide?

The houses which are in steep slopes are the most unsafe.

  • If the house is near steep slopes, and landslides or debris flows have already occurred in the area, it is dangerous.
  • Streams, wetlands, and slope erosion are all signs of potential issues.
  • Slope conditions can also be determined by vegetative characteristics.