Mount St Helens Flashcards
When did Mt St Helens erupt?
18th May 1980 at 8:32
Who’s cabin did pyroclastic flow destroy?
Harry Truman
What type of volcano is Mt St Helens?
Composite
What caused the eruption?
A landslide triggered the eruption but that was caused by a earthquake (5.1 on the Richter scale)
Who now monitors Mt St Helens?
USGS - United States Geological Survey
What is used to monitor the volcano?
Tiltmeters and seismographs are used to monitor the magma chamber and lava dome
Who’s job was it to tell people if the volcano was going to erupt?
David Johnston
What type of blast was it and how big was the wipeout zone?
It was a lateral blast and caused a 27km wipeout zone
Who were called to help the search for survivors?
The army and helicopters
How big was the exclusion zone and why was it put in place?
8km and was put in place to stop people getting to close q
Who was caught in pyroclastic flow?
David Johnston
What was grounded?
All planes around America
How many tourists now visit the area?
3 million
Where was the cryptodome?
On the west side
How are lahars caused?
Ash laying on the ground mixed with rain water (volcanic mudflow)
