Mount St. Helens Flashcards
1
Q
When did Mount St. Helens erupt?
A
1980
2
Q
What had the sufficient gas dissolved under?
A
Pressure
3
Q
What does a lava plug do?
A
Blocks conduit to the summit
4
Q
How far do explosive eruptions send rocks, dust, gas and pyroclastic material into the atmosphere?
A
20km
5
Q
At what rate is material ejected to the atmosphere?
A
100,000 tonnes per second
6
Q
What do the magmas have?
A
Higher levels of silica;
Viscous
