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
The Exploding Lakes of Cameroon What comes to mind when you think of a lake? You probably imagine a pretty scene with blue w
The Exploding Lakes of Cameroon What comes to mind when you think of a lake? You probably imagine a pretty scene with blue w
admin
2014-03-13
50
问题
The Exploding Lakes of Cameroon
What comes to mind when you think of a lake? You probably imagine a pretty scene with blue water, birds, and fish. For the people in the northwestern Cameroon, however, the image is very different. For them, lakes may mean terrible disasters. In 1984, poisonous gases exploded out of Lake Monoun and came down into the nearby villages, killing thirty-seven people. Two years later, Lake Nyos erupted. A cloud of gases rolled down the hills and into the valleys and killed 1, 700 people.
Lake Nyos and Lake Monoun are crater(火山口)lakes. They were formed when water collected in the craters of old volcanoes. The volcanoes under Lake Nyos and Lake Monoun are not active anymore. However, poisonous gases from the center of the earth continue to flow up through cracks in the bottom of the lake. This is normal in a crater lake. In most crater lakes, these gases are released often because the water "turns over" regularly. That is, the water from the bottom of the lake rises and mixes with the water at the top, allowing the gases to escape slowly.
However, in Lakes Nyos and Monoun, there is no regular turning over. No one knows the reason for this fact, but as a result, these lakes have more gases trapped at the bottom than other crater lakes. In fact, scientists who have studied Lakes Nyos and Monoun have found 16, 000 times more gases. When a strong wind , cool weather, a storm, or a landslide(滑坡)causes the water to turn over suddenly, the gases escape in a violent explosion.
In the past, no one knew when the gases might explode, so there was no way for the villagers to escape disaster. Now scientists from the United States, France, and Cameroon have found a way to reduce the gas pressure at the bottom of Lake Nyos. They stood a 672-foot plastic pipe in the middle of the lake, with one end of the pipe near the bottom and the other end in the air. Near the top of the pipe, the team put several holes that could be opened or closed by a computer. Now, when the gas pressure gets too high, the holes are opened and some of the gas-filled water shoots up through the pipe into the air like a fountain. With less pressure, a disastrous explosion is much less likely. However, the scientists are not sure that one pipe will be enough to prevent explosions. They hope to put in others soon and they plan to install a similar pipe and a computer system at Lake Monoun as well.
To protect people nearby until all of the pipes are in place, the scientists have installed early warning systems at both lakes. If the gas pressure rises to a dangerous level, computers will set off loud sirens(警报)and bright lights to warn the people in the villages. In that way, they will have time to escape from the dangerous gases.
Which of the following statements about Lake Nyos and Lake Monoun is true?
选项
A、They were formed in 1984.
B、They are at the top of two active volcanoes.
C、They are not like most other crater lakes.
D、Water in them turns over regularly.
答案
C
解析
根据第二段倒数第二句可知,大多数火山口湖中的湖水会翻转,使有毒气体得以释放,而第三段第一句又表示,Nyos和Monoun中的湖水不会翻转。由此可知,Nyos和Monoun与其他的火山口湖不同。
转载请注明原文地址:https://kaotiyun.com/show/VoGd777K
本试题收录于:
职称英语理工类A级题库职称英语分类
0
职称英语理工类A级
职称英语
相关试题推荐
DriedFoodsCenturiesago,mandiscoveredthatremovingmoisture(51)foodhelpedtopreserveit,andthattheeasiestwaytodot
HighwaysintheUSTheUnitedStatesiswell-knownforitsnetworkofmajorhighwaysdesignedtohelpadrivergetfromoneplac
Duringhislifetimehewasabletoaccumulatequiteafortune.
HowtoSeeFriendshipMorethanfortythousandreaderstolduswhattheylookedforinchosefriendships,whattheyexpected(51)
Thisnewpolicyhasledtoadramaticincreaseinproduction.
MindThoseMannersontheSubwaySo,thereyouare,justsittingthereinthesubwaycar,enjoyingthatbookyoujustbought.(4
HowtoStayYoungIfyouwanttostayyoung,sitdownandhaveagoodthink.ThisistheresearchfindingbyateamofJapan
EyeMovementandSeveralFaultsinReadingSupposeyoudothisexperimentwithafriend.Getholdofabookwithalargepag
A.ReasonsforHIVresistanceB.ImplicationsofchimpanzeeextinctionforhumansC.EffectiveAidstreatmentD.Geneticsimilar
"That’soutrageous!"heprotested.
随机试题
HTTP的正文意思是________。
甲状腺功能亢进症最具特征的临床表现是
《建设工程安全生产管理条例》规定,建设单位在编制()时,应当确定建设工程安全作业环境及安全施工措施所需费用。
办理个人教育贷款时,受理和调查环节面临的操作风险不包括()。
音乐作品的结构涉及多方面的内容,其中主要的要素包括_________、_________、_________、_________。
强制传唤是一种公安行政强制措施。()
以太网交换机工作在OSI的(9),并按照(10)来进行信息转发的决策。它的三种交换模式是碎片丢弃(Fragment Free)交换、(11)。以太网交换机上的每个端口可以绑定一个或多个(12)。当两台交换机级联时,如果下级交换机有Uplink口,则可用(1
有以下程序:#includeintfun(intn){inta;if(n==1)return1;a=n+fun(n一1);return(a);}main()
Whatdoesthewomansayaboutthecolourofviolet?
AsToyotaandHummerhavelearned,growingtoofastcanbeadangerousthing.Fromitsorigins,successintheautoindustr
最新回复
(
0
)