000 KILOMETERS AND TOOK ALMOST 20,000 CORE SAMPLES OF SEABED SEDIM...

600,000 kilometers and took almost 20,000 core samples of seabed sediments and rocks at 624 drillingsites around the world. The Glomar Challenger’s core samples have allowed geologists to reconstructwhat the planet looked like hundreds of millions of years ago and to calculate what it will probablylook like millions of years in the future. Today, largely on thestrengthof evidence gathered duringthe Glomar Challenger’s voyages, nearly all earth scientists agree on the theories of plate tectonics andcontinental drift that explain many of the geological processes that shape the Earth.The cores of sediment drilled by the Glomar Challenger have also yielded information critical

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to understanding the world’s past climates. Deep-ocean sediments provide a climatic recordstretching back hundreds of millions of years, becausethey are largely isolated from the mechanicalerosion and the intense chemical and biological activity that rapidly destroy much land-based evidenceof past climates. This record has already provided insights into the patterns and causes of past climaticchange - information that may be used to predict future climates.Question 43.The author refers to the ocean bottom as a “frontier” becauseitA.is not a popular area for scientific research B. contains a wide variety of lifeformsC.attracts courageous explorers D.is an unknown territoryQuestion 44.The word “inaccessible” is closest in meaning to .A.unrecognizable B.unreachable C.unusable D.unsafeQuestion 45.The author mentions “outer space” because .A.the Earth’s climate millions of years ago was similar to conditions in outer space.B.it is similar to the ocean floor in being alien to the human environment.C. rock formations in outer space are similar to those found on the ocean floor.D. techniques used by scientists to explore outer space were similar to those used in oceanexploration.Question 46.Which of the following is true of the Glomar Challenger?A.It is a type of submarine. B.It is an ongoing project.C.It has gone on over 100 voyages. D.It made its first DSDP voyage in 1968.Question 47.The Deep Sea Drilling Project was significant because it was .A.an attempt to find new sources of oil and gasB.the first extensive exploration of the ocean bottomC. composed of geologists from all over the worldD.funded entirely by the gas and oil industryQuestion 48.The word “they” refers .A.years B.climates C.sediments D.coresQuestion 49. Which of the following is NOT mentioned in the passage as being a result of theDeep Sea Drilling Project?A.Geologists were able to determine the Earth’s appearance hundreds of millions of years ago.B.Two geological theories became more widely accepted by scientists.C. Information was revealed about the Earth’s past climatic changes.D.Geologists observed forms of marine life never before seen.Question 50.How long did the Glomar Challenger conduct its research?A.3 years B.5 years C.15 years D.16 yearsTHE ENDKEY