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A Continent Apart
Antarctica was at one time part of an ancient, considerably larger
land mass, referred to by geologists as Gondwanaland. The supercontinent
began breaking up during the Triassic Period (205-240 million years
ago) and its several segments gradually drifted apart to form the
present continents of South America,
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Mining and
Drilling
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Are there vast deposits of precious metals
and ores beneath the Antarctic ice sheet? Are there huge basins
of gas and oil under the Weddell and Ross seas?
In fact, no strong data show that hydrocarbon
basins exist in the Antarctic. The mineral outcrops which
have been identified are of no economic value, since the expense
of mining and transporting them to markets would be prohibitive.
The Antarctic
Treaty's Protocol on Environmental Protection prohibits
any mining or drilling for at least 50 years.
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Africa, India,
Australia (with New Zealand), and Antarctica.
But the present
outlines of these continents--along with the similarity of their
geology and fossil finds--indicate that they had fitted together
and that Antarctica was not always a cold and inhospitable place.
Coal deposits found today in sandstone beds less than 500 kilometers
from the South Pole show that these materials were laid down during
late Paleozoic time (240-300 million years ago) under marshy conditions
in a cool, moist climate.
Even though less than 1 % of Antarctica's
rock is accessible for direct examination, geologists are
very interested in the continent.
It forms one of the Earth's seven major
rock plates, and its margins are constantly changing, making
it one of the best places in the world to study the movements
of the Earth's crust.
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Geomorphology
is the
study of landforms and in the Antarctic, these
studies have mainly been concerned with the effects of the ice sheet
on the underlying rock, as well as the study of glacial deposits,
and the formation of patterned ground.
Volcanic activity
in Antarctica is limited to only a few places, the most notable
being Mount Erebus on Ross Island. The island is entirely of volcanic
origin, as are White and Black Islands,  Brown
Peninsula and Mina Bluff, and the massifs of Mounts Discovery and
Morning. These are products of eruptions--from the Pliocene through
the present--of basaltic lavas from central cones and fissures at
various locations. Mount Erebus is the largest and by far the most
active of the few volcanoes on the continent, almost continuously
spewing out steam and gases from its summit crater.
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Why study
Geology in Antarctica?
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Paleontologists and glaciologists look
for fossils and glacial features which can provide evidence
of major changes in the extent of the ice sheet and in the
global sea level over the last 5000 years.
Geomorphologists study how extreme climate
can produce such unique landforms as: patterned ground, ice
wedges, and stone polygons.
Soil scientists recognize that Antarctica
contains one of the best climatic archives of the past, with
terrestrial sediments covering the last 200,000 years, marine
sediments covering millions of years and even older areas
of ancient continental rocks.
Geophysicists take advantage of Antarctica's
ideal conditions to study the effects of solar radiation on
the Earth's magnetic field.
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