首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
考研
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 l
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 l
admin
2009-05-24
81
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, 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 drill in very deep waters, extracting samples of sediments and rocks 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 hundred 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.
选项
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
答案
D
解析
frontier的意思是"未经开发利用的边界地区"。第一句话的意思是:海底约为地球表面面积的2.5倍,是一个广阔的未知领域,即使在今天,在很大程度上仍然没有被探索和绘制成图。
转载请注明原文地址:https://www.kaotiyun.com/show/7DYi777K
本试题收录于:
GCT工程硕士(英语)题库专业硕士分类
0
GCT工程硕士(英语)
专业硕士
相关试题推荐
Whatmadeanimpressionontheauthor?Mostofthethingsinthestorewindowwere______.
Thereasonwhythetoysmostboysplaywitharedifferentfromthosethatgirlsplaywithisthat______.Theauthorusedthee
A:Youareacollegestudent.Tellmewhatyouwouldliketodo?B:______.
Accordingtothepassage,somepeoplestartedanationalassociationsoasto______.Accordingtothepassage,opponentsofthe
Patient:Istrainedmybacktheotherdayworkinginthegarden.Doctor:______
Whatdoesthelastsentenceofparagraphoneimply?Afterthedivorce,______.
Daughter:Thejeanslookcool.Mum:______.
OnNewYear’sEve,NewYorkCityholdsanoutdoor______whiehattractsacrowdofamillionormorepeople.
Theme-park-houndbargainseekerswouldbewisetospendsometimesurfingonlinebeforetheygetinlineattheparksthissumme
Manager:______Secretary:Someonedidcall.ButIcanhardlyunderstandthedialectheused.
随机试题
简述预防杂环胺类化合物对人体危害的措施。
患者女,29岁。骑车时摔倒,当时感左膝关节疼痛,活动受限,左小腿外侧感觉减弱,足不能背伸,足背动脉可触及。X线片示左膝关节胫骨向前,股骨下端向后。经上述处理后,神经损伤无修复,应进行处理的是
植物新品种权的审批机关是()
肝硬化时蜘蛛状血管痣发生的主要原因是()
认为人的发展主要依靠外在的力量,诸如环境的刺激和要求,他人的影响和学校的教育等。持这种观点的教育家是()
早餐占一天能量的
2015年6月,刘璋向顾谐借款50万元用来炒股,借期1个月,结果恰遇股市动荡,刘璋到期不能还款。经查明,刘璋为某普通合伙企业的合伙人,持有44%的合伙份额。对此,下列哪些说法是正确的?()
下面四个选项中正确的是()。
中小学生旷课的,学校不需与其父母或监护人取得联系。()
B
最新回复
(
0
)