单选题 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 3,600 meters deep. Totally without fight 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 the Earth.
The cores of sediment drilled by the Glomar Challenger have also yielded information critical to understanding the world"s past climates. Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates. This record has already provided insights into the patterns and causes of past climatic change-information that may be used to predict future climates.
单选题 The author refers to the ocean bottom as a "frontier" in Paragraph 1 because it ______.
【正确答案】 D
【答案解析】[解析] 本题考查推理判断。根据文章第一段第一句“The ocean bottom...is a vast frontier that even today is largely unexplored and uncharted.”可知D项为正确答案。A、B、C三项在文中均未提及。
单选题 The word "inaccessible" underlined in Paragraph 1 is closest in meaning to ______.
【正确答案】 B
【答案解析】[解析] 本题考查词义推断。unreachable“不能达到的”；unrecognizable“未被承认的”；unusable“不能用的”；unsafe“不安全的，危险的”。根据语境可知，inaccessible在此处的意思应为“达不到的，难以接近的”，所以B为正确答案。
单选题 The author mentions "outer space" underlined in Paragraph 1 because ______.
【正确答案】 B
【答案解析】[解析] 本题考查推理判断。根据文章第一段最后一句“...the deep-ocean bottom is a hostile environment to humans, in some ways as forbidding and remote as the void of outer space”可知，作者在此提到outer space是为了说明the deep-ocean bottom is a hostile environment to humans，所以，答案是B。
单选题 Which of the following is true of the Glomar Challenger?
【正确答案】 D
【答案解析】[解析] 本题考查是非判断。第二段中，the Glomar Challenger作the DSDP"s drill ship的同位语，所以A、B两项不正确。根据文章第三段第一句“The Glomar Challenger completed 96 voyages...”可知，C项也不正确。所以，答案是D。
单选题 The word "extracting" underlined in Paragraph 2 is closest in meaning to ______.
【正确答案】 C
【答案解析】[解析] 本题考查词义判断。画线单词extract意为“取出，提取，榨取”；break“打破”；locate“定位，定居”；remove“移动，开除”；analyze“分析，分解”。由此可以判断，答案是C。
单选题 The Deep Sea Drilling Project was significant because it was ______.
【正确答案】 B
【答案解析】[解析] 本题考查事实细节。根据第二段第一句“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).”可以推出，答案是B。
单选题 The word "strength" underlined in Paragraph 3 is closest in meaning to ______.
【正确答案】 A
【答案解析】[解析] 本题考查词义判断。因为on the strength of为固定结构，意为“基于，凭借”，on the basis of意为“在……基础上”，所以，答案是A。B、C、D三项均没有这种结构。
单选题 The word "they" underlined in Paragraph 4 refers to ______.
【正确答案】 C
【答案解析】[解析] 本题考查代词指代。分析“Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates.”这句话的结构可知，they在这里指代的是Deep-ocean sediments。所以，答案是C。
单选题 Deep-ocean sediments provide better information about the world"s past climate because they ______.
【正确答案】 A
【答案解析】[解析] 本题考查事实细节。根据文章第四段第二句“Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates.”可知，深海沉积物提供了一个追溯到几亿年前的气候记录，因为他们在很大程度上远离机械侵蚀和强烈的化学和生物活性，而那些会快速摧毁过去气候的路基证据。由此可推出，答案是A。
单选题 Which of the following is NOT mentioned in the passage as being a result of the Deep Sea Drilling Project?
【正确答案】 D
【答案解析】[解析] 本题考查是非判断。根据第三段第三句“The Glomar Challenger"s core samples have allowed geologists to reconstruct what the planet looked like hundreds of millions of years ago...”可知，A项在文中有所提及；根据第三段最后一句“...nearly all earth scientists agree on the theories of plate tectonics and continental drift that explain many of the geological processes that shape the Earth.”可知，B项在文中有所提及；根据第四段可知，C项也正确。故此题答案是D。