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
外语
Volcanic fire and glacial ice are natural enemies. Eruptions at glaciated volcanoes typically destroy ice fields, as they did in
Volcanic fire and glacial ice are natural enemies. Eruptions at glaciated volcanoes typically destroy ice fields, as they did in
admin
2010-07-06
36
问题
Volcanic fire and glacial ice are natural enemies. Eruptions at glaciated volcanoes typically destroy ice fields, as they did in 1980 when 70% of Mount Saint Helens ice cover was demolished. During long dormant intervals, glaciers gain the upper hand cutting deeply into volcanic cones and eventually reducing them to rabble. Only rarely do these competing forces of heat and cold operate in perfect balance to create a phenomenon such as the steam caves at Mount Rainier National Park.
Located inside Rainier’s two ice-filled summit craters, these caves form a labyrinth of tunnels and vaulted chambers about one and one-half miles in total length. Their creation depends on an unusual combination of factors that nature almost never brings together in one place. The cave making recipe calls for a steady emission of volcanic gas and heat, a heavy annual snowfall at an elevation high enough to keep it from melting during the summer, and a bowl-shaped crater to hold the snow.
Snow accumulating yearly in Rainier’s summit craters is compacted and compressed into a dense form of ice called firn, a substance midway between ordinary ice and the denser crystalline ice that makes up glaciers. Heat rising from numerous openings (called fumaroles) along the inner crater walls melts out chambers between the rocky walls and the overlying ice pack. Circulating currents of warm air then melt additional opening in the firn ice, eventually connecting the individual chambers and, in the larger of Rainier’s two craters, forming a continuous passageway that extends two-thirds of the way around the crater’s interior.
To maintain the cave system, the elements of fire under ice must remain in equilibrium. Enough snow must fill the crater each year to replace that melted from below. If too much volcanic heat is discharged, the crater’s ice pack will melt away entirely and the caves will vanish along with the snow of yesteryear. If too little heat is produced, the ice, replenished annually by winter snowstorms, will expand, pushing against the enclosing crater walls and smothering the present caverns in solid firn ice.
In the last paragraph, "smothering" the present caverns means that they would be ______.
选项
A、eliminated
B、enlarged
C、prevented
D、hollowed
答案
A
解析
结合语境可知,此处指的是冰会将坑洞填平,即消除坑洞。因此选A。根据词义也可推断,smother in表示“覆盖,掩盖”。因此选A。
转载请注明原文地址:https://kaotiyun.com/show/udJd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
Whatdoesthespeakersuggestthatthestudentsshoulddoduringtheterm?
Defendersofspecialprotectivelaborlegislationforwomenoftenmaintainthateliminatingsuchlawswoulddestroythefruitso
"Junkscience"ishowElliotMorley,Britain’sministerresponsibleforgeneticallymodifiedfarming,describesstudiesthatcla
Oneofthemostalarmingthingsaboutthecrisisintheglobalfinancialsystemisthatthewarningsignshavebeenouttherefo
TheAmundsen-ScottSouthPoleStationmadeheadlinesinAprilwhenthedoctorforthatremotesciencefacilitywastakenserious
TheAmundsen-ScottSouthPoleStationmadeheadlinesinAprilwhenthedoctorforthatremotesciencefacilitywastakenserious
WhatcanbesaidaboutthereportbytheNationalAcademyofSciences?
Genetherapyandgenebaseddrugsaretwowayswecouldbenefitfromourgrowingmasteryofgeneticscience.Buttherewillbeo
Revolutionaryinnovationisnowoccurringinallscientificandtechnologicalfields.Thiswaveofunprecedentedchangeisdriven
随机试题
我国的行政监察机构包括()
根据我国《仲裁法》第4条规定,当事人采用仲裁方式解决纠纷,应当双方自愿,达成仲裁协议。没有仲裁协议,一方申请仲裁的,仲裁委员会不予受理。下列说法正确的是:
在文章层次中经常使用篇段合一式的是()
一般来讲,研究教育现象和教育问题,揭示教育规律的科学是()。
人民警察离休,退休的,其警衔()。
关于应菲律宾共和国单方面请求建立的南海仲裁案仲裁庭于2016年7月12日作出的裁决,中华人民共和国外交部郑重声明,该裁决是无效的,没有拘束力,中国()。
省政府要建设群众信访接待中心,需要了解各地信访工作的落实情况。现在领导派你到各市、县、乡针对各自的信访工作进行调查。你会怎么开展此次调查?
以下关于我国法律在处理宗教问题上的作用的说法中,不正确的是()
从1840年至1919年的80年间,中国在历次反侵略战争中失败的最重要的原因是
(1)Inthego-goyearsofthelate1990s,noeconomictheoristlookedbetterthanJosephSchumpeter,theAustrianchampionofcap
最新回复
(
0
)