Compare a violent volcano eruption and the explosion from an atomic bomb. Compare a violent volcano eruption and the explosion from an atomic bomb. There is also no radioactivity associated with volcanic eruptions. It is interesting to note that one of the volcanic phenomena that turns out to be pretty common, was first figured out by watching films of atomic explosions.
Most atomic explosions generate the famous huge mushroom cloud, with a big vertical column.
It was realized that a volcanic explosion that occurs near or at the surface would also generate a cloud with a strong horizontal component to it, and sure enough, during the 1965 eruptions at Taal in the Philippines, such explosions were observed. They are called base-surges and they are most often associated with phreatomagmatic eruptions. They are relatively dilute and usually relatively cool, turbulent, fast-moving, destructive blasts of ash and larger debris. Because they move mostly horizontally they are essentially a very dusty wind, and they form structures very much like sand dunes. I hope this comparison has helped a little bit.