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1995年8月托福考试阅读理解全真试题上

时间:2021-09-06 17:00:42 托福英语 我要投稿

1995年8月托福考试阅读理解全真试题(上)

Question 1-9

1995年8月托福考试阅读理解全真试题(上)

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 Earth s 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 Foundation s

Deep Sea Drilling Project (DSDP). Using techniques first

developed for the offshore oil and gas industry, the DSDP s drill

ship, the Glomar Challenger, was able to maintain a steady

position on the ocean s 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 Glomar Challenger s

core samples have allowed geologists to reconstruct what the

planet looked like hundreds of millions of years ago and to

calculate what it will probably look like millions of years in the

future. Today, largely on the strength of evidence gathered

during the Glomar Challenger s voyages, nearly all earth scientists

agree on the theories of plate tectonics and continental

drift that explain many of the geological processes that shape

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