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
9
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 word "inaccessible" underlined in Paragraph 1 is closest in meaning to______.
选项
A、unrecognizable
B、unreachable
C、unusable
D、unsafe
答案
B
解析
词义题型。inaccessible达不到的,难以接近的;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。
转载请注明原文地址:https://tihaiku.com/zcyy/3922695.html
相关试题推荐
Theheatinsummerisnoless______hereinthismountainregion.A、concentratedB
Itisknowntoallthatchildreninthisregionhavestrong______toswimmingin
Attemptshavebeenmadefornearlythreedecadestoincreasetheamountofpreci
Foralongtimeinthatvastregion,thislawwasinabeyance.A、activeuseB、dou
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
Theoceanbottom—aregionnearly2.5timesgreaterthanthetotallandar
随机试题
Thepocketcalculatorhasbeenrelegatedtotheroleofagraphiciconondi
邮政部门、电信部门属于()A.信息存储服务业 B.信息传播服务业 C.信息
下列哪种辅酶包含腺嘌呤?( )A.CoA B.FAD C.NADH D.
以下所列的过程中,()的过程能用△S=△H/T这一公式。A.真实气体绝热可逆膨胀
凡从事建筑装饰装修的企业,必须经建设行政主管部门进行资质审查,并取得资质证书后,
ASP的()对象可以向服务器提供浏览器版本信息。A.Request B.Res
体温调节中枢功能失常所致的发热见于A、中暑 B、脑膜炎 C、大叶性肺炎
经过50多年的发展,我国台湾地区资本市场建立起由“证券交易所集中市场—上柜市场—
1998-131.营分证候的病机特点是 A.营阴受损B.津液耗竭C.心神
工程项目的绿色施工方案应包括()。A.提高质量标准措施 B.降低成本措施
最新回复
(
0
)