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The U. S. Geological Survey Alaska Mineral Resources Team
conducts unbiased research on the occurrence, quality, quantity,
and availability of mineral resources in order to help the Nation
make informed decisions using earth-science information. |
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Alaska
is one of the most geologically active areas in the world. The surface
of the earth has numerous large plates, sections of the earths crust
that move about the surface, crashing into each other, grinding
past each other, and overrunning one another. Alaska is home to
one of the most active plate boundaries on the planet, where the
Pacific Plate is being forced under (or subducting under) the North
American Plate at rates greater than 7 cm/year (just under 3 inches/year).
Though this process forms much of the magnificent mountain ranges
and peaks in Alaska.
The
process also brings to Alaska earthquakes and volcanoes. Alaska
is the most seismically active state in the U.S. by a large margin
and one of the most active areas in the world. Three of the six
largest earthquakes ever recorded world-wide occurred in Alaska
as did seven of the 10 largest in the U.S.
Similarly,
the plate movements produce one of the most active volcanic arcs
in the world. Roughly 10% of the worlds active volcanoes are in
Alaska and on average, 1-2 erupt each year. The largest eruption
in the 20th century was at Katmai on the Alaska Peninsula in 1912.
Though many of Alaska's volcanoes are in the remote Aleutians, volcanic
ash resulting from eruptions any of these volcanoes pose a significant
hazard to the aviation industry, including the wide-body jets flying
the North Pacific air routes between North America and Asia.
The
Hazards Office of the Alaska Science Center is the focal point
for U.S. Geological Survey earthquake and volcano work in Alaska.
Scientists in the Hazards Office work closely with USGS scientists
outside Alaska as members of national teams striving to understand
better seismic and volcanic processes in order to minimize loss
of life and property resulting from their inevitable occurrence.
In Alaska, the Hazards Office also works closely with partners
at the University Of
Alaska Fairbanks Geophysical Institute, the State
of Alaska Division of Geological and Geophysical Surveys,
and the West Coast & Alaska
Tsunami Warning Center to fulfill the USGS's congressionally-mandated
responsibility to issue warnings of earthquake- and volcano-related
hazards. Congress authorized the U.S. Geological Survey to issue
warnings of geologic-related hazards, including earthquakes and
volcanoes. (Public Law 93-288, Federal Register vol. 42, No 70,
page 19292, April 12, 1977). Through formal partnerships such
as the Alaska Volcano Observatory and the Alaska Earthquake Information
Center, work by the partners agencies are presented to the public
as a common voice.
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