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
23
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
[originaltext]Whatcolordoyoulike?[/originaltext][audioFiles]2021m12x/audio
Themomentumisbuildingaheadofnextmonth’sG8summitinScotlandwheret
It’sa(47)______oftenrequestedinlonelyheartsadsandscientistshaven
采用工程量清单计价,建设工程造价由下列何者组成?Ⅰ.分部分项工程费;Ⅱ.措施项目
下列关于食品添加剂的说法,错误的是A.食品添加剂应当有标签、说明书和包装 B.
()能使教师及时了解学生在该阶段的音乐学习情况,及时反馈教学信息,发现学生音
A.朱砂B.石菖蒲C.柏子仁D.合欢皮E.首乌藤有疏肝解郁、宁心安神功效的药物是
各种运输方式内外部的各个方面的构成和联系,就是( )。 A.运输系统
单位支取定期存款只能以转账方式将存款转入其()账户。A.一般存款
关于无效合同,说法正确的是()。A.造成对方人身伤害的免责条款无效 B.
最新回复
(
0
)