Web posted
Monday, April 5, 2004
|
Researchers from the Alaska Volcano Observatory check instruments near Mount Redoubt's active cone. Redoubt is one of the four active volcanoes visible from the Kenai Peninsula.
Clarion file photo
|
Volcanoes: The fire beneath the ice
The western shore of Cook Inlet offers one of the most dramatic and potentially lethal views from the Kenai Penin-sula. Some of the world's most active volcanoes face the penin-sula, just across the waters of the inlet.
Though the range has been dormant for more than a decade, any one of the volcanic peaks could erupt at any time.
The Chigmit Mountains, the range across from the peninsula, are part of the "Ring of Fire," a string of volcanic and seismic hot spots that circles the Pacific Ocean.
Beneath the Gulf of Alaska, the North Pacific geologic plate slides beneath the continental shelf about as fast as fingernails grow, pushing up the young mountains in the Kenai Peninsula, Kodiak and Prince William Sound areas. The crust becomes molten as it's forced down toward the planet's interior. If the molten rock finds a fault or fissure, it can be forced miles back up to the surface to become lava.
However, Alaska volcanoes spew more ash than lava. Inlet volcanoes have endangered aircraft many times in the recent past by spewing plumes of airborne ash that blankets the ground, while hot rock and boiling mud avalanche down their slopes.
The Alaska Volcano Observatory in Anchorage monitors the region. It posts information about the peaks and updates on their activity on its Web site at fm.gi.alaska.edu/.
Volcanoes visible from the peninsula, north to south, are:
Mount Spurr at 11,070-feet tall, lies nearly due west of Anchorage. It erupted in 1953 and 1992, dumping ash on the city and closing its airport.
Mount Redoubt, the 10,197-foot symmetrical peak, dominates the western horizon from the central peninsula. Beginning Dec. 14, 1989 and extending into 1990, it sent mushroom clouds of ash to an altitude of 12 miles. The eruption shut down air traffic and threatened the Drift River Oil Terminal. It also erupted from 1966 to 1968.
Mount Iliamna, 10,016-feet tall and just south of Redoubt, has been quiet in historic times. Glaciers radiate from its rambling multiple peaks.
Mount Augustine near Homer occupies its own island in Kamishak Bay. The cone rises 4,025 feet. Young and restless, Augustine erupted in 1963, 1976 and 1986. It poses an additional threat because its unstable dome could break apart, fall into the sea and generate a tsunami.
Mount Douglas is the southernmost inlet volcano. The 7,000-foot peak has not erupted in historic times, but scientists report activity since the last ice age.
The western shore of Cook Inlet offers one of the most dramatic and potentially lethal views from the Kenai Penin-sula. Some of the world's most active volcanoes face the penin-sula, just across the waters of the inlet.
Though the range has been dormant for more than a decade, any one of the volcanic peaks could erupt at any time.
The Chigmit Mountains, the range across from the peninsula, are part of the "Ring of Fire," a string of volcanic and seismic hot spots that circles the Pacific Ocean.
Beneath the Gulf of Alaska, the North Pacific geologic plate slides beneath the continental shelf about as fast as fingernails grow, pushing up the young mountains in the Kenai Peninsula, Kodiak and Prince William Sound areas. The crust becomes molten as it's forced down toward the planet's interior. If the molten rock finds a fault or fissure, it can be forced miles back up to the surface to become lava.
However, Alaska volcanoes spew more ash than lava. Inlet volcanoes have endangered aircraft many times in the recent past by spewing plumes of airborne ash that blankets the ground, while hot rock and boiling mud avalanche down their slopes.
The Alaska Volcano Observatory in Anchorage monitors the region. It posts information about the peaks and updates on their activity on its Web site at fm.gi.alaska.edu/.
Volcanoes visible from the peninsula, north to south, are:
Mount Spurr at 11,070-feet tall, lies nearly due west of Anchorage. It erupted in 1953 and 1992, dumping ash on the city and closing its airport.
Mount Redoubt, the 10,197-foot symmetrical peak, dominates the western horizon from the central peninsula. Beginning Dec. 14, 1989 and extending into 1990, it sent mushroom clouds of ash to an altitude of 12 miles. The eruption shut down air traffic and threatened the Drift River Oil Terminal. It also erupted from 1966 to 1968.
Mount Iliamna, 10,016-feet tall and just south of Redoubt, has been quiet in historic times. Glaciers radiate from its rambling multiple peaks.
Mount Augustine near Homer occupies its own island in Kamishak Bay. The cone rises 4,025 feet. Young and restless, Augustine erupted in 1963, 1976 and 1986. It poses an additional threat because its unstable dome could break apart, fall into the sea and generate a tsunami.
Mount Douglas is the southernmost inlet volcano. The 7,000-foot peak has not erupted in historic times, but scientists report activity since the last ice age.
|
