Скачать или смотреть 45th anniversary of the 1980 eruption of Mount St. Helens

🌋Today marks the 45th anniversary of one of the most dramatic geologic events in American history - the May 18, 1980 eruption of Mount St. Helens.

After lying dormant for over a century, signs of unrest for the eruption begin in March of that year when a swarm of earthquakes shook inside the mountain. With each tremor a new pathway was opened for the magma and volcanic gases to rise upwards.

As the weeks passed, pressure built within the volcano causing the north flank to bulge ominously.

Then, on the morning of May 18, the slope gave way in a massive landslide—followed instantly by a devastating lateral blast.

Traveling at over 650 mph, the eruptive blast flattened 230 square miles of pristine Pacific Northwest wilderness. Volcanic mudflows, known as lahars, surged through valleys, carrying debris all the way to the Columbia River. Ash from the eruption rose high into the atmosphere and drifted east, eventually reaching as far away as Minnesota.

All told, 57 people lost their lives, including USGS scientist David A. Johnston, and billions of dollars in damage was done to the region.

When the ash finally settled, Mount St. Helens stood 1,300 feet shorter than before.

The eruption didn’t just reshape the mountain—it transformed how we study, monitor, and prepare for volcanic hazards around the world.

➡️Watch USGS scientists recount their experiences before, during, and after the eruption here: https://ow.ly/iRFX50VU88O

📸1: Eruption contrasted with the quiet countryside. Skamania County, Washington. Credit: USGS
📸 2: Aerial view pre-eruption, circa 1979. Credit: Rick Hoblitt, USGS
📸 3: Bulge on the north slope before the eruption. Sugar Bowl on the left side of the bulge and Goat Rocks on the right side. Credit: Robert Tilling, USGS
📸 4: Aerial view looking south, after the eruption. Credit: R.M. Krimmel, USGS.

#MountStHelens #VolcanoAwarenessMonth #NaturalHazards #Volcanoes #MSH45 #MountStHelens1980
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