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Naturaldisasters-----Earth’scryingAsweallknow,Japanwashitbyanearthquake,magnitude9.0ataround2:46pm3.11.2011.ThisisthebiggestearthquakeIhaveeverheardsofarinmylife.ViewsofJapan’searthquakeAccordingtolatestnews,Japan’searthquakehascaused9523peopledeathand16067peoplemissed.Atotalof363,000victimslosttheirhomesEvenworse,nuclearpowerplantshadexperiencedbreakdownsintheircoolingsystemsasaresultoftheearthquake,andsmallamountsofradiationleakedfromthebothplants.Howmuchdoyouknowaboutanearthquake?Manypeopledied……Peoplelosttheirhomes….Manythingsweredestroyed…..DoyouknowwhatistheEarthquake?Andwhatcanbecausedbytheearthquake?Haveyoueverseenearthquakeshappeningaroundyou?Whatmayhappenbeforeanearthquake?Doyouknowhowtosuriviveinanearthquake?TheOriginofEarthquake:Earthquakeshappenbecausetheouterlayeroftheearth(thecrust)isslowlybeingdeformedbystressesthatareplacedonthecrust.Thesestressesbuildupalonglockedportionsofthecrustwhereearthquakefaults(断层)are.Eventuallythestressesbecometoogreatforoneofthefaultstowithstand(承受),andthecrustsuddenlymoves,likeaspringthathasbeenwoundtootightly.Thissuddenmovementofthegroundiscalledanearthquake.What’searthquakeAnearthquakeistheresultofasuddenreleaseofenergyintheEarth'scrustthatcreatesseismicwaves(地震波).Sometimesanearthquakehasforeshocks.Therearesmallerearthquakesthathappeninthesameplaceasthelargerearthquakethatfollows.Scientistscan’ttellthatanearthquakeisaforeshockuntilthelargerearthquakehappens.123Earthquakeswithmagnitude3orloweraremostlynotawared(wemaynotfeelit),butearthquakeswithmagnitude7cancauseseriousdamageoverlargeareas.earthquakehazard(地震危害性)uproottreesandknockoffbuildingsmaketheriverschangetheircoursesmakethetransportationsystembreakdowncausepowerlinefailurescauselossoflifeandpropertytriggerlandslides,floodingandtsunamismaycauseinfectivedeseasesEarthquakesareamongthemostpowerfuleventsonearth,andtheirresultscanbeterrifying.Asevereearthquakemayreleaseenergy10,000timesasgreatasthefirstatomicbomb.Whatdoyouthinkmayhappenbeforeanearthquake?1)Theweatherwillbecomeworsethanusual.Therewillbestrongwind,heavyrainandbrightlightintheskyandsoon.2)Animalswillbecomenervous.e.g.micewillrunabout;fishjumpoutofponds;cows,pigs,horsesanddogswillbeupset.3)Waterinriversandwellswillrisesandfalls.4)Wewillseecracksinthewellsandthesmellygaswillcomeoutofthecracks.…SignsWhatshallwedoifanearthquakehappens?DiscussionWhatcanwedowhentheearthquakehappensRunHoldonCalmStopCarefulIfyouareoutdoorsIfyouareinthecarIfyouarenearthedoorIfyoucan’trunoutofthehouseintimeDuringtheearthquakedropontothegroundkeepawayfromthepowerlinesWaysonself-rescuekeepawayfromthesignskeepawayfromthebuildingshideunderthefurnituredropontothegroundholdontothefurniturehideinthecornerofthehouseSomeseriousearthquakesinthehistory1923:Kanto,Japan:onSeptember1,1923,anearthquakemeasuring7.9sentshockwavesthroughtheTokyo-YokohamaareaandcausedNearly143,000peopledied.1976:Tangshan,China:nearlytheseconddeadliestearthquakeonrecordinchina2004:IndianOceanTsunami:onDec.26,2004a9.2magnitudeearthquakerockedthebottomoftheIndianOcean,theofficialdeathtollwas227,8982008,5.12:SichuanProvince,China:The7.9-magnitudedisasterdestroiedmillionsofbuildingsandcausedanestimated$86billionworthofdamageHowmanyotherNaturalDisastersdoyouknow?WhatareNaturalDisasters?NaturalDisastersaredisastersthatoccurinthisworldnaturally.◦Naturaldisasterscanhappenatanylocationatanytimethroughouttheuniverse.Naturaldisasterscandestroycities,orsometimesawholecountryifitisthatsevere.Theycanoccuronland,inthewater,andwiththeweather.seismicseawave/tsunamivolcaniceruptionthunderstormfloodfireTsunamisAtsunamiisaseriesofwaterwavesItiscausedbythedisplacementofalargevolumeofabodyofwater,suchasanocean.Effects:Tsunamisarecapableofcausingasubstantialamountofdamage.Onetsunamicandestroyanentirecoastalvillageandremoveallthesandfromabeachandsandthattookhundredsofyearstoaccumulate.OntheDecember26,2004,astrongearthquakehittheIndianOcean.Andtheearthquakeandtsunamicauseover300000deathsandmanyinjuries,andmillionsofpeoplearemadehomeless.droughtAdroughtisanextendedperiodofmonthsoryearswhenaregionnotesadeficiencyinitswatersupply.Generally,thisoccurswhenaregionreceivesconsistentlybelowaverageprecipitation.ThreeTypesofDroughtMeteorologicaldroughtAgriculturaldroughtHydrologicaldroughtSofar,theimpactofthedroughttothenaturalreserveisnotlarge,butitspotentialimpactisthreateningfuturegenerationsofwildanimalsandplantsFloodsFloodsareamongthemostfrequentandcostlynaturaldisasters.Conditionsthatcausefloodsincludeheavyorsteadyrainforseveralhoursordaysthatsaturatestheground.Flashfloodsoccursuddenlyduetorapidlyrisingwateralongastreamorlowlyingarea.TyphoonTyphoonscometocoastalcitiesinsummertimeorfallseason.Theyaregreatwindstorms.Whentheystrikelandtheymaydogreatdamages.PeoplecanboarduptheirwindowsanddomanyotherthingstoprotectthemselvesiftheyknowaboutaTyphoonintime.Tosumup:Nowadays,astheindustryandeconomicdevelopment,naturaldisastershavebecomemoreandmorefrequently,environmentalsobecomemoredegradationSo,environmentalprotect
本文标题:英语-口语-地震-自然灾害-earthquake-and-natural-disasters
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