How the Earth was Made - Mt. St. Helens

How many major eruptions does the Cascade Range produce per century, on average?

1 or 2 every 100 years

What year was the previous eruption of St. Helens witnessed by local Native American tribes?

1857

Mt St. Helens is one of _____ volcanic mountains that make up the ______ Range of the western United States.

20, Cascade

How many times larger was the eruption of Mt. St. Helens compared to the atomic bomb dropped on Hiroshima?

27,000 times

How quickly was the bulge on St. Helens' northern flank growing in the day leading up to the eruption?

450 feet

How many people died in the 1980 eruption of Mt. St. Helens?

57

What is the name of the ridge where geologists set up a trailer and monitoring equipment just before the eruption?

Cold- water ridge

What was the name of the young geologist who was stationed at cold-water ridge on the day of the eruption?

David Johnston

What is the main factor that determines the explosiveness of the eruption?

Gases

What natural disaster immediately preceded the major eruption?

Landslide

The previous eruption of the volcano on the U. S. mainland was _________ Peak in California in 1915.

Lassen

Through St. Helens created massive, explosive, ash eruptions in recent history, there is also evidence of slow, quiet _______ _______ produced in the past.

Lava flows

St. Helens erupted on what date?

May 18th, 1980

The science learned through the close monitoring of the St. Helens eruption helped scientists make accurate predictions and save lives in the 1997 eruption on the Caribbean island of ________.

Montserrat

Mt. St. Helens produced 3 major natural disasters- a landslide, an eruption, and a __________. Scientist call this event a __________.

Mudflow, Lahar

What is the name of the famous lake that has been blasted out to create mudflows multiple times in Mt. St. Helen's eruptive history.

Spirit Lake

What volcanic gas is associated with predicting volcanic activity?

Sulfur Dioxide

Explain what the movement of monitor JRO 1 suggested about what is happening under Mt. St. Helens as recently as 2006.

The magma was shrinking

True or False: Mt. St. Helens is still considered an active volcano capable of erupting again in the future.

True