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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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