更多"The ocean bottom a region nearly 2."的相关试题:
[单项选择]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, bidden beneath waters averaging over 3 600 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 dr
A. is not a popular area for scientific research
B. contains a wide variety of life forms
C. attracts courageous explorers
D. is an unknown territory