0004年 老托福阅读全套真题.doc
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目录
1995.08 4
1995.10 14
1995.12 24
1996.01 34
1996.05 44
1996.08 54
1996.10 64
1996.12 74
1997.01 84
1997.05 94
1997.08 104
1997.10 114
1997.12 124
1998.01 134
1998.05 144
1998.08 154
1998.10 164
1999.01 174
1999.05 184
1999.08 194
1999.10 203
2000.01 212
2000.05 221
2000.08 231
2000.10 241
2001.01 250
2001.05 260
2001.08 270
2001.10 280
2002.01 290
2002.05 300
2002.08 310
2002.09 320
2002.10 330
2003.01 340
2003.08 350
2003.10 360
2004.01 370
2004.05 380
2004.08 390
2004.10 400
2005.01 410
2005.05 420
2005.08 430
1995.08
Question 1-9
Investigation of the Deep-Ocean
Keywords: ocean, researchers, techniques, samples, rocks
The ocean bottom – a region nearly 2.5 times greater than the total land area of the Earth – is a vast frontier that even today is largely unexplored and uncharted. Until about a century ago, the deep – ocean floor was completely inaccessible, hidden beneath waters averaging over 3,6000 meters deep. Totally without light and subjected to intense pressures hundreds of times greater than at the Earths surface, the deep – ocean bottom is a hostile environment to humans, in some ways as forbidding and remote as the void of outer space.
Although researchers have taken samples of deep – ocean rocks and sediments for over a century, the first detailed global investigation of the ocean bottom did not actually start until 1968, with the beginning of the National Science Foundations Deep Sea Drilling Project (DSDP). Using techniques first developed for the offshore oil and gas industry, the DSDPs drill ship, the Glomar Challenger, was able to maintain a steady position on the oceans surface and drill in very deep waters, extracting samples of sediments and rock from the ocean floor.
The Glomar Challenger completed 96 voyages in a 15 – year research program that ended in November 1983. During this time, the vessel logged 600,000 kilometers and took almost 20,000 core samples of seabed sediments and rocks at 624 drilling sites around the world. The Glom
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