Mount St. Helens erupted 43 years ago Thursday: Here's how it unfolded

While the most devastating acts from the eruption of Mt. St. Helens occurred on May 18, 1980, scientists began getting an inkling something was up a little more than two months before the eruption. The USGS released a day-by-day rundown reliving those anxiety-ridden weeks.

What are the largest earthquakes to strike the US?

There have only been a handful of notable earthquakes to strike the U.S. greater than the magnitude 7.8 earthquake that recently struck Turkey and Syria. The earliest dates back to 1700.