60 people were dead or missing. In the following nine hours, volcanic ash rose more than 15 miles into the air, later to land in troublesome amounts as far away as Montana. Before the eruption, Mount St. Helens towered about a mile above its base, but during the eruption, its top slid away in an avalanche of rock and other debris. When finally measured about six weeks later, the mountain's height had been reduced by 1,313 feet. In these images, ash, mudslides, and mud-laden rivers show as grayish blue.
Water looks black.
Ice and snow are white and vegetation is red. Patchwork block patterns, where forest has been cut, are visible east of Mount St. Helens.