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
Earthquake Can Scientists Predict Killer Earthquakes? The date was November 23,1980.People near Naples,in Southern Italy
Earthquake Can Scientists Predict Killer Earthquakes? The date was November 23,1980.People near Naples,in Southern Italy
admin
2010-07-24
45
问题
Earthquake
Can Scientists Predict Killer Earthquakes?
The date was November 23,1980.People near Naples,in Southern Italy,felt the earth roll and shake. Earthquake! Suddenly buildings came tumbling down. Cracks appeared in the earth.Within minutes,entire towns were destroyed.Thousands of people were dead.Thousands more were injured.
As rescuers searched through the rubble,many people must have wondered,if only the victims had known ahead of time,many lives could have been saved.
Actually,an Italian scientist did predict that such a quake would happen.In 1977 Dr.M.Caputo of the Universite Degiles Studi in Rome warned that a large quake would soon strike the east of Naples.Unfortunately,he couldn’t predict the exact time and date of the quake.
Dr.Caputo made his general prediction after talking with scientists at 54 earthquake-monitoring stations throughout Italy.He learned that many earthquakes had recently rocked different areas around Naples.But none had occurred in one particular spot east of Naples for many years.Dr. Caputo felt that the area was long overdue for a large quake.And it was.
Earthquake Strikes in Gap
The quake occurred in a region that Dr.Caputo called a seismic gap.A seismic gap is an area in an active earthquake region where no earthquake or seismic activity has been recorded in a long time.Seismic gaps are located where two large plates in the earth have become stuck.
When the plates slide past each other,they sometimes became locked in place.A similar thing happens when you make a running leap on a sidewalk while wearing sneakers.When you 1and on both feet,the sneakers grab onto rough surface.Friction tends to hold your feet back while the rest of your body goes forward.You may end up falling flat on your face.
In the case of plates,however,the uneven surfaces between the plates cause the plates to remain locked in place for years.Huge pressure builds up behind each plate.Periodically,a shudder,or tremor,is recorded as some of this energy is released.
Finally,after about 50 years,rock in the seismic gap either suddenly breaks or moves under the great stress.This sudden release of energy sends shock waves through the rock layers above.The ground shakes,sidewalks crack,and buildings tumble.A mighty quake has struck.
Gaps Used to Predict Quakes
Many geologists have used what is called the seismic gap technique to accurately predict earthquakes.The technique was first developed by Soviet earthquake expert Dr.V.Fodotov during his studies of ancient and recent Japanese earthquakes.Dr.Fodotov was marking the location,size,and date of all known quakes in Japan when he noticed a striking pattern.
All major earthquakes were found to occur in only a few isolated spots in Japan.Each of these spots,he noted,experienced a major quake only once every 50 to 60 years.Dr.Fodotov concluded that spots that hadn’t had a quake in more than 50 years were “ripe” for a quake.The Russian scientist named these locations seismic gaps.
In the past several years,geologists from other countries have found seismic gaps in other parts of the world.After making detailed studies of past quakes in these regions,the geologists were able to make an accurate prediction of when a quake would occur.
How Do Animals Know When an Earthquake Is Coming?
Scientists who try to predict earthquakes have gotten some new helpers recently-animals.
That’s right,animals.Scientists have begun to catch on to what farmers have known for thousands of years.Animals often seem to know in advance that an earthquake is coming,and they show their fear by acting in strange ways.Before a Chinese quake in1975,snakes awoke from their winter sleep early only to freeze to death in the cold air.Cows broke their halters and tried to escape.Chickens refused to enter their coop.All of this unusual behavior,as well as physical changes in the earth,alerted Chinese scientists to the coming quake. They moved people away from the danger zone and saved thousands of lives.
One task for scientists today is to learn exactly which types of animal behavior predict quakes. It’s not an easy job.First of all not every animal reacts to the danger of an earthquake.Just before a California quake in 1977,for example,an Arabian stallion became very nervous and tried to break out of his stall.The horse next to him,however, remained perfectly calm.It’s also difficult at times to tell the difference between normal animal restlessness and “earthquake nerves”.A zookeeper once called earthquake researchers to say that his cougar had been acting strangely.It turned out that the cat had an upset stomach.
A second task for scientists is to find out exactly what kind of warnings the animals receive.They know that animals’sense far more of the world than humans do.Many animals can see,hear,and smell things that people do not even notice.Some can detect tiny changes in air pressure,gravity,or the magnetism of earth.This extra sense probably helps animals predict quakes.
A good example of this occurred with a group of dogs.They were penned up in an area that was being shaken by a series of tiny earthquakes.Several small quakes often come before or after a large one.Before each quake a low booming sound was heard.Each boom caused the dogs to bark wildly.Then the dogs began to bark during a silent period.A scientist who was recording tile quakes looked at his machine.It was acting as though there was a loud noise too.The scientist realized that the dogs had reacted to a booming noise.They also sensed the tiny quake that followed it.The machine recorded both,though humans felt and heard nothing.
In this case there was a machine to monitor what the dogs were sensing.Many times,however,our machines record nothing out of the ordinary,even though animals know a quake is coming.The animals might be sensing something we do measure but do not recognize as a warning.Discovering what animals sense,and learning how they know it is a danger signal,is a j ob for future scientists.
During an earthquake in China 1975,cows______.
选项
A、broke their halters and tried to escape
B、awoke from their winter sleep early only to freeze to death in the cold air
C、refused to enter their coop
D、ran away from their sheds
答案
A
解析
细节题。根据题目中的Cows找到小标题How Do Animals Know when an Earthquake Is Coming下第二段第五句Cows broke their halters and tried to escape. (牛挣断缰绳,试图逃跑)。这道题的答案是A。
转载请注明原文地址:https://kaotiyun.com/show/vqN7777K
0
大学英语四级
相关试题推荐
PreparingforTestsIdeallyitshouldbeloveoflearning,achievement,andself-improvementthatpromptsalllearning.But
Wecanseehowtheproductlifecycleworksbylookingattheintroductionofinstantcoffee.Whenitwasintroduced,mostpeopl
Thiswould____________(证明非常有益)toapersonwhomayhavelostabodyorgansuchasakidney,scientistscouldclonethatparticul
Oceanographyhasbeendefinedas"theapplicationofallsciencestothestudyofthesea".Beforethe19thcentury,scientists
Oceanographyhasbeendefinedas"theapplicationofallsciencestothestudyofthesea".Beforethe19thcentury,scientists
Newtechnologylinkstheworldasneverbefore.Ourplanethasshrunk.It’snowa"globalvillage"wherecountriesareonlyseco
Ourconclusionisbasedonknowledge____________(而不是基于猜测和想象)
Modernscientistsdividetheprocessofdyingintotwophases--clinicalortemporarydeathandbiologicaldeath.Clinicaldeath
Shesaysshe’drather_____________(宁愿明天走而不是今天).
随机试题
B2B是按照电子商务的()分类的。
We’rehavingameetinginhalfanhour.Thedecision______atthemeetingwillinfluencethefutureofourcompany.
下列有关急性胰腺炎引发的腹痛叙述正确的是()。
根管消毒不宜采用下列哪种药物
A、莨菪碱B、番木鳖碱C、延胡索D、山莨菪E、雷公藤士的宁又称()。
阅读下文。回答下列几题:原始地球形成后的八亿年,其内部逐渐变热使局部熔融并超过铁的熔点,原始地球中的金属铁、镍及硫化铁熔化,并因密度大而流向地球的中心部位,从而形成液态铁质地核。同时,地球的平均温度进一步上升(可达约2000℃),引起地球内部大部
肖群一周工作五天,除非这周内有法定休假日。除了周五在志愿者协会,其余四天肖群都在大平保险公司上班。上周没有法定休假日。因此,上周的周一、周二、周三和周四肖群一定在大平保险公司上班。以下哪项是上述论证所假设的?
设α1,α2,…,αn是一组n维向量,证明它们线性无关的充分必要条件是任一n维向量都可由它们线性表示。
函数fun的功能是:将a、b中的两个正整数合并形成一个新的整数放在c中。合并的方式是:将a中的十位和个位数依次放在变量c的十位和千位上,b中的十位和个位数依次放在变量c的个位和百位上。例如,当a=45,b=12。调用该函数后,c=5241。注意
Whatdidthequestionerwanttoknow?Hewantedtoknowsomethingabout______.WhowouldbeinterestedintheQuestionandAn
最新回复
(
0
)