Mount St. Helens 

America’s most famous volcano, Mount St. Helens, could be primed for another deadly eruption.Geoscientists say that a swarm of earthquakes has intensified to the point that there are now 40 a week.The earthquakes could be a clue that magma is building up under Mount St. Helens, much as did before the famous eruption on May 18, 1980. That event was the deadliest volcanic explosion in American history, killing 57 people, pumping 540 million tons of ash into the air and triggering the largest landslide in recorded history. The ash cloud spread as far at the central US. The quakes are more vigorous than swarms of quakes in 2012 and 2014, he wrote, explaining that they are generated by the shifting of rocks by magma or lava building up underground. Last year, United States Geological Survey scientists discovered that there are two giant magma chambers underneath Mt. Helens. When the chambers become completely full of magma, Mount St. Helens or other nearby volcanoes like Mount Adams go off.