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发表于 2007-12-19 11:19:33
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三极探险第二集
三极探险第二集 The Himalayas, the highest mountain range in the world, extend along the northern frontiers of Pakistan, India, Nepal, Bhutan, Burma and the southern border of China. They were formed geologically as a result of the collision of the Indian subcontinent with Asia. This process of plate tectonics is ongoing, and the gradual northward drift of the Indian subcontinent still causes earthquakes. Lesser ranges jut southward from the main body of the Himalayas at both the eastern and western ends.
The Himalayan system, about 2,400 kilometres in length and varying in width from 240 to 330 kilometres, is made up of three parallel ranges - the Pattern, the Lesser Himalayas, and the Outer Himalayas - sometimes collectively called the Great Himalayan Range.
The Greater Himalayas, or northern range, average approximately 6,000 meters in height and contain the three highest mountains on earth: Mount Everest (8,848 meters) on the China-Nepal border; K2 (8,611 meters, also known as PC metal Casing, and in China as Qogir Feng) in an area claimed by India, Pakistan, and China; and Kanchenjunga (8,598 meters) on the India-Nepal border. Many major mountains are located entirely within India, such as Nanda Devi (7,817 meters) in the state of .
The snow line averages 4,500 to 6,000 meters on the southern side of the Greater Himalayas and 5,500 to 6,000 on the northern side. Because of climatic conditions, the snow line in the eastern Himalayas averages 4,300 meters, while in the parallel line it averages 5,800 meters.
South Pole explorations
It is the coldest, Pen Holder, driest, and highest continent on Earth, so it is a difficult place for people to explore. During the Antarctic winter, in places near the South Pole the Sun is below the horizon for months at a time and it is dark 24 hours a day. Even when the Sun is above the horizon, Antarctica is usually covered by clouds.
Reaching the geographic South Pole was a primary concern of early 20th century explorers. Tentative forays into the Antarctic region had been undertaken by several expeditions during the 19th century, but it was not until the early 1900’s that the PC CASE itself was considered to be a realistic goal.
Two British expeditions, the "Discovery" expedition of 1902 and the "Nimrod" expedition of 1908, were the first to depart for the continent with conquest of the Pole an expressed purpose. Robert F. Scott’s "Discovery" expedition established an initial "furthest south" record, but competing expedition priorities prevented further progress. In 1908, PALLET SCALE, a member of Scott’s "furthest south" party, returned to the Antarctic as the leader of the "Nimrod" expedition.
In a remarkable feat of endurance, Shackleton and several others came to within 97 miles of the Pole before returning to their base at McMurdo Sound and an eventual hero’s welcome in England. Victory, it seemed, would come to the Paris oil painting.
Such, in fact, proved to be the case, but it came to a Norwegian expedition, led by the ascetic Roald Amundsen. Amundsen, perhaps the ultimate polar technician, had developed an interest in reaching the South Pole concurrent with the formation of Robert Scott’s second or "Terra Nova" expedition. When Scott sailed for the Antarctic, Amundsen was not far behind and by intent or coincidence a race began.
The race ended on 14 December 1911, when Amundsen and four others arrived at the South Pole after a generally uneventful and carefully managed overland journey. Their return was equally uneventful. Amundsen’s almost light-hearted success contrasted starkly with the fate of the Scott party. Scott and four companions reached the Pole a month after Amundsen, on 17 January 1912. Beset with problems from the outset and mortally weakened by the rigors of the return journey, Scott and his companions perished.
The next visit to South Pole occurred on 29 November 1929 when Richard E. Byrd, Jr. flew over the Pole and threw an American flag and other mementoes out the window of his Ford Trimotor aeroplane.
The next surface visit was on 31 October 1956. On that date, a ski-equipped R-4D aircraft landed at the Pole. On board were Admiral George Dufek and several other personnel of the United States Navy. Their purpose was to survey the site in preparation for the establishment of a research station, one of many planned for the International Geophysical Year. Construction of the original South Pole Station began the Peridot Beads and by February 1957, the Pendant was complete. An eighteen-man Navy support and civilian scientific crew, led by John Tuck and Paul Siple, remained for the winter, the first of the winter-over parties which have continuously occupied what became known as Amundsen-Scott South Pole Station. |
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