The Antarctic Treaty Secretariat
(ATS)--is active in maintaining the treaty agreements. They enacted the Edinburgh (Scotland) Antarctic Declaration on the International Polar Year 2007-2008.
"We--the Antarctic Treaty Parties--are meeting in Edinburgh, Scotland from 12 to 23 June 2006 for the XXIXth Antarctic Treaty Consultative Meeting. Our discussions of the international management of Antarctica are this year enhanced by a full day's consideration of the International Polar Year 2007-2008 and its importance for our Antarctic future."
The treaty was completed on December 1, 1959 and entered into force on June 23, 1961, by the governments of Argentina, Australia, Belgium, Chile, the French Republic, Japan, New Zealand, Norway, The Union of South Africa, the Union of the Soviet Socialists Republics, the United Kingdom of Great Britain and Northern Ireland, and the United States of America.
With it, the signing governments agreed on certain specifics, such as the following:
Other, newer issues are addressed and settled as they arise.
Why Study Earth Science in Antarctica?
Antarctica's central position in the supercontinent of Gondwana (Africa, Antarctica, Australia, South America, India, Madagascar) makes it a key place for paleontologists in understanding how plant and animals have evolved over time. Collecting rock samples in Antarctica to study fossils is a relatively new branch of paleontology.
Geologists collect terrestrial rocks and marine sediment drill cores to understand the past global climate and ocean circulation.
Geophysics is the study of rocks beneath the ice through the use of radar, magnetic, and gravity measurements. Recent aeromagnetic findings suggest a very large meteorite impact site is buried beneath the ice in East Antarctica .Some scientists believe it is one of the largest yet discovered.
Geologists and geophysicists study Antarctica to see where the continent was located over the course of Earth's history. The distribution of the continents directly affects global climate and the evolution of life..
Glaciologists look for glacial features that can provide evidence of major changes in the size of the ice sheets and global sea level.
Oceanographers study characteristics and properties of the oceans, such as the changes in sea ice, water temperature, currents and interactions with their land boundaries.
Background Science Information
The current Theory of Plate Tectonics has been developing over the last century beginning with the theory of continental drift, first developed by the German astronomer, meteorologist, and climatologist Alfred L. Wegener. He was one of several geologists in the early 19th and 20th centuries that were intrigued by the seeming fit between the Atlantic coasts of South America and Africa.
Many people who had seen maps of the South Atlantic, including South America and Africa, could easily notice how one coastline seemed to match the other. One difference with Wegener was that he began to study the observation as a scientist; searching for scientific answers to questions such as "Were South America and Africa ever truly in contact with each other? What kind of evidence would it take to show that they were? How could such evidence be collected?"
After many years of collecting and examining evidence, Wegener proposed a dramatic idea based on his findings. In 1912, he proposed that millions of years ago Earth's continents were one large continent that broke apart and drifted to where they are now located. He created the name Pangaea for this supercontinent. In addition to matching coastlines of the two continents of South America and Africa, Alfred Wegener also used fossil distribution and lithological similarities as evidence.
As with many new scientific ideas, Wegener's theory was not initially accepted. Some scientists thought that the evidence was not strong enough to support the theory, nor was the underlying cause of the drift on the continents explained; some claimed it was simply impossible.
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Two other theories were prevalent in Wegener's time. One theory stated that the continents and basins were fundamentally unchanged in their present positions and configurations since their formation. Those who accepted this theory were called "Permanentists/" The opposing belief was that, as the result of a gradual contraction on the solid Earth, parts of the ocean floor became dry land, and dry land, in turn became ocean floor. These scientists were called "Contractionists."
One enthusiastic supporter of Wegener, however, was South African geologist, Alexander DuToit. He spent five months in South America collecting fossil evidence in Brazil, Uruguay, and Argentine that he compared to fossils he collected in Africa. He found that the samples from both South America and Africa contained the same plant and animal fossils embedded in rock, layer-by-layer, in the same complex sequence.
DuToit eventually proposed that at one time there were two supercontinents; a southern one he called Gondwana that consisted of South America, Africa, Antarctica, Australia, and India. He named the northern supercontinent Laurasia, and it consisted of North America, Europe, the regions around the Arctic, and the rest of Asia.
It took the development of two new fields of science--paleomagnetism and oceanography--to give the strongest support to both Wegener's and DuToit's theories.
The geographical distribution, layering, and relative frequency of fossils from different parts of the Earth can be compared to determine if there are any similarities and how frequently they occurred. The fossil distribution of many plants and animals provide evidence that they lived at the same time and in the same place, very long ago. Although it was the same place then, the locations are very different now, and are sometimes separated by thousands of miles. The evidence Wegener collected supported the concept that these two areas were very likely joined at some time in the distant past. As the scientific community began to accept his explanations about the supercontinent, more skepticism remained about how such massive continents could possibly move across the surface of the Earth.
The study and description of macroscopic features of a rock, such as texture and structure, is called lithology. Lithological similarities between rocks from different parts of the world indicate that they were formed by the same geologic processes. The more characteristics the rock samples had in common with each other, the more likely it was that they were undergoing the same processes at the same time, and in the same location. This overlapping of characteristics and properties again provided evidence that the areas where the samples originated were once connected.
This field of study is based on the principle that, in molten igneous rocks and unlithified sediments, magnetic particles (iron ore) will align themselves with the Earth's magnetic field. When he igneous rocks containing the magnetic particles cool, and the sediments lithify, the magnetic record is stored within the rocks.
British experimental physicist Patrick Blackett developed a sensitive device called the astatic magnetometer in the 1940s. With this instrument, it became possible to detect the orientation of very weak magnetic fields, allowing researchers to conduct paleomagnetic studies of rocks whose magnetism could not previously be measured.
When compared to the current direction of the Earth's magnetic field, changes in the alignment of the magnetic particles in different layers of rocks showed that the particles were in different positions at some time in the past. Since the rock layers were, and are, part of the continents, the inference, then, is that the continents have been moving.
In 1932, a scientist named Henry Hess became a geology professor at Princeton University, and later, during World War II, he served as a Navy commander. One of the ships he commanded was equipped for sounding the ocean floor using echo-sounding technology. His wartime duties included searching for enemy submarines, and his equipment enabled him to do his job. During the long voyages to new locations, he and his crew used the equipment to collect data that became useful to Hess as a geologist.
In the early 1960s, as the theory of plate tectonics became more accepted throughout the scientific community, Hess thought of studying the data he had collected during WW II while in the Pacific. He examined the data for evidence that might connect loose ends in the plate tectonics theory, and spent a considerable amount of time studying the sounding records gathered as his ship had crisscrossed the Pacific. The results provided him with the first good image of ocean floor characteristics.
Hess gathered additional significant information about the midoceanic ridges and volcanic valleys of both the Atlantic and Pacific Oceans through further exploration. His meticulous record-keeping and his ability to analyze the data he collected enabled Hess to contribute one of the most influential theories in the geological sciences of the 20th century.
This momentous contribution explained the mechanics of how the continents might have moved as Wegener theorized in 1912. Hess wrote a paper explaining his ideas in 1962, after years of intensive study of the data he collected during WW II. He proposed that molten magma from beneath the Earth's crust could ooze up between the plates in the Great Global Rift. As this hot magma cooled in the ocean water, it expanded and pushed the plates on both sides of it -- North and South America to the west and Eurasia and Africa to the east. This way, the Atlantic Ocean widens, but the shapes of the continental coastlines did not change dramatically.