Do earthquakes occur in Antarctica?
Earthquakes do occur occasionally in Antarctica, but not very often.
See http://www.iris.edu/seismon/. There
have been some big earthquakes--including one magnitude 8--in the
Balleny Islands (look "south" from the Pole toward New Zealand between
the coast and the plate boundary on the Pacific-Antarctic Ridge). The
boundary between the Scotia Plate and the Antarctic Plate just grazes
the north tip of the Antarctic Peninsula (again, look "northwest" from
the Pole toward South America). There is also a hint of a line of
seismicity off the west coast of the Antarctic Peninsula and some
activity in the Kerguelen Plateau (in the Indian Ocean "northeast" from
the Pole). The Kerguelen Plateau is within the Antarctic Plate but it
is not part of the Antarctic Continent. As with the interior area of
all tectonic plates, earthquakes can and do occur in Antarctica, but
they are much less frequent than quakes on the plate boundaries.
There is also another reason why there are fewer quakes located in Antarctica than within other plates such as Australia or North America. It is because smaller quakes are much more likely to go undetected in Antarctica because there are very few seismograph stations. There are only 19 operating seismograph stations (as of 2005)in all of the continent of Antarctica, and only one of them, at the Amundsen-Scott South Pole Station, is in the interior of the continent. By comparison, our files show 42 stations listed as open within the State of New Mexico. The closest seismograph station to the one at South Pole is 1350 km or about 840 miles. That's a big area to hide little earthquakes in!
Finally, the interior of Antarctica has icequakes which, although they are much smaller, are perhaps more frequent than earthquakes. The icequakes are similar to earthquakes, but occur within the ice sheet itself instead of the land underneath the ice. Some of our polar observers have told us they can hear the icequakes and see them on the South Pole seismograph station, but they are much too small to be seen on enough stations to obtain a location.
- OH Community
- Web Apps
- About Us