首页
登录
职称英语
The ocean bottom — a region nearly 2. 5 times greater than the total land ar
The ocean bottom — a region nearly 2. 5 times greater than the total land ar
游客
2025-01-21
7
管理
问题
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 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 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. [br] The Deep Sea Drilling Project was significant because it was______.
选项
A、an attempt to find new sources of oil and gas
B、the first extensive exploration of the ocean bottom
C、composed of geologists from all over the world
D、funded entirely by the gas and oil industry
答案
B
解析
细节题型。参看第二段第一句…the first detailed global investigation of the oceanbottom.
转载请注明原文地址:https://tihaiku.com/zcyy/3922699.html
相关试题推荐
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
Insuranceisthesharingof【C1】________Nearlyeveryoneisexposed【C2】_______
随机试题
Thehunter-gatherertribesthattodaylivelikeourprehistorichuman【M1】__
[audioFiles]2016m8x/audio_ezfj_ezflisteningd_201607_175[/audioFiles]Corpora
家庭所在的社会文化传统"规定"而形成的权威,属于A.传统权威型 B.分享权威型
金融远期合约主要包括()。 Ⅰ.远期利率协议 Ⅱ.远期外汇合约 Ⅲ
如图所示粪便标本中的虫卵是( )。 A.钩虫卵 B.鞭虫卵 C.血吸虫卵
颈外静脉穿刺时正确的进针角度是A:持穿刺针与皮肤呈45°进针,入皮后呈25°穿刺
广义教育与狭义教育(学校教育)的根本区别是()A.目的性 B.计划性
下列太阳系行星中,已证实拥有卫星最多的是:( )A.地球 B.木星 C.水
适应障碍是指在遭遇生活事件后,()起病。 (A)2个月到3个月内(
关于羊水及其功能,以下哪项正确A.胎儿尿液为羊水的重要来源 B.羊水与胎儿的交
最新回复
(
0
)