Alaska still bears marks of epic, 3-day volcanic eruption 100 years on
June 4, 2012, 12:04 am TWN
ANCHORAGE, Alaska -- Even a century after one of the world's largest volcanic eruptions, a strong wind still whips up the ash that rained down on what became known as Alaska's Valley of Ten Thousand Smokes. Pumice chunks still dot the beaches of Kodiak Island across Shelikof Strait.
The three-day explosion that began June 6, 1912, spewed ash as high as 100,000 feet (30,000 meters) above the sparsely populated Katmai region, covering the remote valley to depths up to 700 feet (210 meters). The volcanic cloud spread across the United States and traveled as far as Algeria in northern Africa in the most powerful eruption of the 20th century and one of the five largest in recorded history.
Remarkably, there were no eruption-related deaths, although the ash-filled air was believed to be a contributing factor in the death of an elderly Kodiak-area woman who had health problems that included tuberculosis.
The eruption killed an untold numbers of animals and plants and decimated salmon populations in the region until they began recovering in the 1920s.
An estimated 3 cubic miles of magma and debris beneath Mount Katmai exploded through the vent of Novarupta 6 miles (10 kilometers) to the west, an event that today could ground planes across a wide swath of the globe. The magma drainage caused Katmai's summit to collapse, creating an oblong caldera 2 miles (4 kilometers) across and filled with a lake more than 800 feet (240 meters) deep.
Scientists still don't completely understand the unique plumbing system involving the two separate volcanos, why magma moved laterally from its storage reservoir to create a new vent instead of exploding through Mount Katmai's existing vent, said U.S. Geological Survey geologist Tina Neal, who is based at the Alaska Volcano Observatory in Anchorage.
Novarupta, Latin for new eruption, had 45 times the magma volume that erupted in the 1980 Mount St. Helens explosion in Washington state and has supplied a wealth of research material and better understanding of how explosive volcanoes work. But there is plenty still to learn, scientists say.
To mark the centennial anniversary of Novarupta, events are planned around Alaska throughout the year. Lectures are scheduled. A field trip to the moonlike valley is planned for high-school students whose ancestors had to abandon villages in the region located at Katmai National Park and Preserve.