Solving the Mystery of the Tibetan Plateau
University of Alberta
EurekAlert
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A University of Alberta physicist who helped solve the age-old mystery of what keeps afloat the highest plateau on earth has added more pieces to the Tibetan puzzle. Dr. Martyn Unsworth has uncovered new research about the Tibetan Plateau--an immense region that for years has plagued scientists studying how the area became so elevated.
Several years ago, Unsworth and a team of scientists from China and the United States used low-frequency radio waves to detect that the mid-crust of the plateau is like "a big waterbed." The hot, molten rocks supporting the plateau are less dense than cold rocks, which means they rise up slowly, similar to the way a hot-air balloon works.
The discovery provides an explanation for how the whole of Tibet could rise up over millions and millions of years. After that finding, Unsworth returned to Tibet and has since learned that this geological makeup is typical of the whole length of the Himalaya, not just a small region.
"We initially thought that this layer might be a local structure, but it's not so," says Unsworth. His results are published in the current edition of the scientific journal, "Nature." Dubbed "the roof of the world," or the "adobe of the Gods," the plateau contains not just Mount Everest but almost all of the world's territory higher than 4000 metres.
The area was formed when India rammed into Asia about 50 million years ago and is considered a showcase of plate tectonics. Although many theories have been proposed to explain the unusual thickness of the plateau--its crust doubles the average 30 to 35km thickness found the world over--little concrete evidence has been offered.
Tibet was closed to foreign access until the 1980s, when French scientists first collaborated with Chinese scientists to investigate the plateau. Since then Unsworth and his international research team have made many significant findings and has recently negotiated access to data collected in India.
Nov 04, 2005
University of Alberta
EurekAlert
________
A University of Alberta physicist who helped solve the age-old mystery of what keeps afloat the highest plateau on earth has added more pieces to the Tibetan puzzle. Dr. Martyn Unsworth has uncovered new research about the Tibetan Plateau--an immense region that for years has plagued scientists studying how the area became so elevated.
Several years ago, Unsworth and a team of scientists from China and the United States used low-frequency radio waves to detect that the mid-crust of the plateau is like "a big waterbed." The hot, molten rocks supporting the plateau are less dense than cold rocks, which means they rise up slowly, similar to the way a hot-air balloon works.
The discovery provides an explanation for how the whole of Tibet could rise up over millions and millions of years. After that finding, Unsworth returned to Tibet and has since learned that this geological makeup is typical of the whole length of the Himalaya, not just a small region.
"We initially thought that this layer might be a local structure, but it's not so," says Unsworth. His results are published in the current edition of the scientific journal, "Nature." Dubbed "the roof of the world," or the "adobe of the Gods," the plateau contains not just Mount Everest but almost all of the world's territory higher than 4000 metres.
The area was formed when India rammed into Asia about 50 million years ago and is considered a showcase of plate tectonics. Although many theories have been proposed to explain the unusual thickness of the plateau--its crust doubles the average 30 to 35km thickness found the world over--little concrete evidence has been offered.
Tibet was closed to foreign access until the 1980s, when French scientists first collaborated with Chinese scientists to investigate the plateau. Since then Unsworth and his international research team have made many significant findings and has recently negotiated access to data collected in India.
Nov 04, 2005
