Question

question 4
0.5 pts
what were the effects of the eruption of mount st. helens in 1980?
it released a basaltic lava flow that moved downslope quickly, resulting in the death of 304
people
it blew straight up into the air and spread ash all around the world, which cooled global
temperatures by 3 degrees celsius
it released a large pyroclastic flow, blew down trees over a wide area, and spread ash east
across the united states

Explanation:

• The eruption of Mount St. Helens in 1980 was a violent explosive eruption. Basaltic lava is more fluid and associated with effusive eruptions (not the case here), so the first option is wrong.
• The eruption did not cool global temperatures by 3 degrees Celsius. Volcanic eruptions like Pinatubo had more significant global - cooling effects (but not 3 degrees for St. Helens).
• The eruption released a large pyroclastic flow. The lateral blast blew down trees over a wide area, and ash was spread east across the United States.

Answer:

It released a large pyroclastic flow, blew down trees over a wide area, and spread ash east across the United States.