posted by m .
Judging from the sizes of the before-and-after craters atop Mount St. Helens, which volcani event appears to have been more explosive, the last one before 1980, or that which occured in 1980?
I thought it would be the one before 1980 since that would have created the upheaval for the 1980 one. Am I right?
Try some of the following links, as I don't believe my first answer posted: