Is Mount St. Helens dormant

Answer 1

No, it is not. Mount St. Helens is an active stratovolcano, and there is a bulge within its current crater area that is growing while you read this.

Mount Saint Helens is not a dormant volcano. For 123 years it was thought to be, however a bulge was noticed in the volcano, and evacuation orders took place. 57 people refused to evacuate, one of whom was 83-year-old Harry R. Truman. On Monday 8:32:17 a.m May 18, 1980, the "bulge" fell off, or slid down the mountain, exposing partly melted and gas enriched rock to lower pressure. It exploded with enough fury to send an 80,000 foot high ash column into the sky, depositing ash into 11 states.

At the same time, snow, ice, and several entire glaciers on the volcano melted, forming a series of large lahars (Volcanic mudslides) that reaches as far as the Columbia River, nearly fifty miles (eighty kilometers) to the south. 200 homes, 27 bridges, 15 miles (24 km) of railways and 185 miles (300 km) of highway were destroyed. Currently it is active.

As I learned in my natural disasters class, after a volcano has finished with it's current "explosion", it starts to rebuild itself by excluding a toothpaste consistency glob of Rhyolite. Mount Saint Helens is active in the way that it is rebuilding itself using the "glob", however it is still an Active Volcano.

If it helps any, a Dormant volcano is thought to be a "sleeping" volcano, and is simply one that currently isn't active but is capable of acting. Extinct volcanoes haven't erupted for tens of thousands of years, and aren't expected to erupt again. Mt. St. Helens is an active volcano.

Answer 2

Volcanoes become dormant normally after every time they have erupted. Dormant means sleeping. They can wake up again.

Volcanoes become extinct when the crust moves away from the hot spot and the volcano is separated from the magma in the asthenosphere. Making it inactive.

Answer 3

Pressure has subsided in the magma column that feeds Mount St Helens since July 10, 2008, and seismic activity has returned to background levels. Scientists do not know why. It is likely that the volcano is not truly dormant and that future activity is to be expected, but there is presently no way to predict when that might be. I suggest you keep in touch with the US Geological Survey which maintains a geological observatory there, and perhaps they will learn something helpful in the near future. See the link below.

Answer 4

Because it's continental and oceanic plates are still very active