上海某中學(xué)2021-2022學(xué)年高二下學(xué)期期末英語試卷（含詳解）

上海市進才中學(xué)2021學(xué)年第二學(xué)期期末練習(xí)

高二英語

LListeningComprehension（25分）

SectionA

Directions:InSectionA,youwillheartenshortconversationsbetweentwospeakers.Atthe

endofeachconversation,aquestionwillbeaskedaboutwhatwassaid.Theconversationsand

thequestionswillbespokenonlyonce.Afteryouhearaconversationandaquestionaboutit,

readthefourpossibleanswersonyourpaper,anddecidewhichoneisthebestanswertothe

questionyouhaveheard.

1.A.6:45.B.6:15.C.5:45.D.5:30.

2.A.Ordersometakeoutfromarestaurant.

B.Makeamealbythemselves.

C.Gooutandfindsomethingtoeat.

D.Visittheirfriends5houseandhaveamealtogether.

3.A.Husbandandwife.B.Bossandsecretary.

CCustomerandwaitress.D.Passengerandattendant.

4.A.Johnnydevoteslesstimebutgainsmoreachievements.

B.Mandydoesn'tcontributeallherenergytoherwork.

C.Mandycan'treachthetopevenifshebecomesmoreattentive.

D.Johnnyisnolongerunreachable.

5.A.Thetimetofinishthereportissolimited.

B.Thedeadlinewillbesurelyextended.

C.Staffwanttoassignsomeextrataskstostudents.

D.StudentsshoulduploadtheirinformationbythemselvesbeforeDecember22nd.

6.A.Hewongreatpopularity.B.Hegothurtintheperformance.

C.Hedidn'tdoagoodjob.D.Heamazedhisfans.

7.A.Gobacktoapplyforthejobagain.B.Thinkaboutwhethertoquitthejob.

C.Getsometrainingbeforequittingthejob.D.Applyforanotherpart-timejob.

8.A.Hewasslightlyhurtintheaccident.

B.Hewasluckilysavedbythedoctor.C.Hewaslookingforwardtohisfriend'shelp.

D.Heshouldtakealongerbreakbecauseofhisinjury.

9.A.Marywasdismissedbythecompanyforsomeprivateaffairs.

B.TheimmigrationofMary'sfamilywassuchanemergency.

C.Maryquitherjobregardlessofherworkprospect.

D.Mary'sfamilyforcedhertogiveupherworkforthefamily.

10.A.Thewomanistheman'sboss.

B.Themanwantstobeassuccessfulasthewoman.

C.Thewomankeepsabalancebetweenworkandfamily.

D.Thewomanishumble.

SectionB

Directions:InSectionB,youwillheartwoshortpassagesandalongerconversation,andyou

willbeaskedsomequestionsonthepassagesandtheconversation.Thepassagesandthe

conversationwillbereadtwice,butthequestionswillbespokenonlyonce.Whenyouheara

question,readthefourpossibleanswersonyourpaperanddecidewhichoneisthebestanswer

tothequestionyouhaveheard.

Questions11through13arebasedonthefollowingpassage.

11.A.Queenstown.B.Melbourne.C.NewSouthWales.D.Sydney.

12.A.Australiahasneverbeenstruckbybushfiresbefore.

B.ResidentsinNoosaaremoreaccustomedtofloodsratherthanflames.

C.CoffsHarbourissufferingthebiggestfireinAustralia.

D.Thebushfireshavebeenextinguishedwiththehelpoffirefighters.

13.A.Thesummerseason.B.Thelackofawareness.

C.Thedensityofforests.D.Theweather.

Questions14through16arebasedonthefollowingpassage.

14.A.Exerciseleadsonlytomodestweightlosswithoutdietchanges.

B.Exercisecanmakepeoplelosetheirweightasexpected.

C.Hopingtoloseweightsometimeswouldberuinedduetobadhabits.

D.Peoplecanloseextraweightinanappropriateway.

15.A.Theydidn'tgetanycheck.

B.Theywereunwillingtojointheresearch.C.Theywereheartdiseasepatients.

D.Theywereheavyandyoung.

16.A.Thegroupwhichexercisedmostlostmoreweightthanexpected.

B.Thenon-exercisegroupgainedfivepoundsinweight.

C.Thegroupwhichexercisedmoderatelylostthemostoftheirweight.

D.Thethreegroupsalmosthavenodistinction.

Questions17through20arebasedonthefollowingconversation.

17.A.Onlyhecanmanagetodothat.

B.Ourplanetisnotlargeenoughtosupportusinthefuture.

C.Thatprogramcanmakehimlivebetter.

D.Hethinksitisinspiring.

18.A.Depressing.B.Appealing.C.Exhausting.D.Thrilling.

19.A.Thefutureisincrediblydepressing.

B.Sustainableenergycanbeachievedsoonerorlater.

C.Technologyjustautomaticallyimproves.

D.Thereisnoneedforustospeedupspacetravelprogram.

20.A.Ifnotspeedingup,technologywillslowdownsurely.

B.Technologywasthesameasthegreatcivilizationsinancient.

C.Egyptiansdevelopedtechnologyinmakingthepyramids.

D.Romansforgothowtoimprovetechnologyinwaterways.

ILGrammarandVocabulary

SectionA(15分)

Directions:Afterreadingthepassagebelow,fillintheblankstomakethepassagecoherentandgrammatically

correct.Fortheblankswithagivenword,fillineachblankwiththeproperformofthegivenword;fortheother

blanks,useonewordthatbestfitseachblank.

Chekhov(契科夫)wrotemorethan500shortstories,which,intermsofdepthandartistry,rivalthegreat

novelsofotherwriters.Hewasthefirst](focus)notonoverblowndrama,butoneverydaylife.Maxim

GorkywrotetoChekhovthatnoonecouldequalhimwhenitcameto2(write)aboutthesimplethings.

“Afterreadingevenyour3(insignificant)story,everythingelseseemscrude,writtennotwithapen,but

withalog.^^

Hereare2ofthemasterstoryteller^must-reads.1.TheChameleon《變色龍》，1884

AminorepisodeoccursonthemarketsquareofthecityofN:adogbitesthefingerofthegoldsmith

Khryukin.PoliceinspectorOchumelovarrivestosortouttheissue.Atfirst,theinspectorexclaimsthattheanimal

4beputdownanditsownerfined.Butwhenhelearns5thedogbelongstoageneral,his

opinionchanges.Allofasudden,Khryukinis6（blame）forprovokingtheanimal.

OneofChekhov9sfirststories,readbyallschoolchildren,itisahumorouscritiqueofhowpeople'sattitudes

changechameleon-like,depending7whotheyaredealingwith.

2.ManinaCase,1898

Eveninwarmweather,Belikovwearsacoatandcarriesanumbrellainacase.Infact,allhispossessionshave

theirownpersonalcase.Hehideshisfacebehindhiscollar.Suspiciousandparanoid,hecravesorderandneatness

in8.Onlyinhiscoffin9hewearanalmostcheerfulexpressiononhisface.

InRussian,thephrase“maninacase“hasbecomeanidiom,saidaboutpeople10areafraidtoopen

uptotheworldandlosemanyopportunitiesbyneverleavingtheircomfortzone.

SectionB（15分）

Directions:Completethefollowingpassagebyusingthewordsinthebox.Eachwordcanonlybeusedonlyonce.

Notethatthereisonewordmorethanyouneed.

A.chaoticallyB.comparedC.correspondingD.grantedE.numberingF.portion

G.positionH.representI.royalJ.substantiallyK.unlocked

ThemethodbywhichthegreaterpartoftheEgyptianalphabetwas11isthis:Theoval口，?！?/p>

“cartouche“asitiscalled,alwayscontaineda（n）12name.ThereisonlyonecartoucheontheRosetta

StoneconcerningaPtolemy.IfthecartouchedidcontainthenameofPtolemy,whoruledoverEgypt,thecharacters

initwouldhavethesoundsoftheGreekletters,andthatalltogethertheywould13theGreekformofthe

nameofPtolemy.Ontheobelisk（方尖碑）whichMr.BankeshadbroughtfromPhilae（菲萊，埃及一地名），there

isaninscriptionintwolanguages,EgyptianandGreek.IntheGreek14,twosacrednamesare

mentioned,PtolemyandCleopatra,andonthesecondfaceoftheobeliskaretwocartouches.Whenthese

cartoucheswere15withtheoneontheRosettaStone,onecontainedhieroglyphic（象形文字的）

charactersalmostidenticalwiththoseontheRosettaStone.

RosettaStoneObeliskfromPhilaeGgSHtHIS

TakingthecartouchessupposedtocontainthenamesofPtolemyandCleopatrafromthePhilaeObelisk,and

16thesigns,wehave:Ptolemy,A.

（g區(qū)3日6qq,8乎A2N13夕

Cleopatra,B.（[立川響A6心為占個d]

No.1inAandNo.5inBareidentical,andjudgingbytheir17inthenames,theymustrepresentthe

letterP.No.4inAandNo.2inBareidentical,andtheymustrepresenttheletterL.A'sListhesecondletterinthe

nameofCleopatra,No.1/mustrepresentK.

theGreekformofCleopatra,there

aretwovowelsbetweentheLandtheR18tothetwohieroglyphs,Qand豺,soQ=Eand曰=O.

InsomeformsofCleopatra,No.7replacedby,identicalwithNo.2inAandNo.10inB.A'sT

followsPinthenamePtolemy,andasthereisaTintheGreekformofCleopatra,andhave

19thesamesoundofT.IntheGreekformofCleopatratherearetwoa's,thepositionsofwhichagree

withNo.6andNo.9,soacanbe20thevalueofA.Substitutingthesevaluesforthehieroglyphsin

B,wemaywriteitasthus:

1810"""ll*N

（KLBOPAT<zx>AQGReadingComprehension

SectionA（30分）

Directions:Foreachblankinthefollowingpassagestherearefourwordsorphrasesmarked

A,B,CandD.Fillineachblankwiththewordorphrasethatbestfitsthecontext.

（A）

Wordsworthiscelebratedasthenaturepoetbecauseofhisbeautifuldescriptionsofnatureand

rural/countrysideareas.However,to21hisworktojustanimitationoftreesandflowerswouldbe

immature.

Wordsworthadmirednature/countrysidenotonlybecauseitlookedbeautiful,butbecauseofthesimplicityand

beautythatnature/countrysideprovidedallowedpeopletobein22withtheirsoulandexperiencetrue

beautyinlife.Wordsworthbelievedthatthecitylifemadethemassesdullanddepressed—ithadreducedthemto

23machineswhofailedtoappreciatethesimplebeautyoflife.Hecalledthismentalstatesavagetorpor

（原始麻木）.

24ofthehighlyelevatedtopicsofneoclassical（新古典主義）poetsandtheirover-complicated

language,Wordsworthwanted“tomaketheordinaryextraordinary,,.Wordsworthfound25from

everydayfiguresofeverydaylife.WhetheritbethefamousSolitaryReaperortheDajfodils-Wordsworth's

poetryflowstoadmirethesimplebeautythatexistsindailylife.

ForWordsworth,apoetissimply“amanspeakingtomen“一afellowhumanjustlikeallofustryingto

communicatehis26andexperienceoftruthandbeauty.27、thepoetdiffersfromregularpeople

becauseofhishighersensitivitytothehappeningsaroundhimandadeeperconnectionwithhisownfeelings,

moodsandemotionsastheyarisein28totheseouterhappenings.

Wordsworthfamously29poetryas"aspontaneousoverflowofpowerfulfeelingswhichare

recollectedintranquility”.Simplyspeaking,thehighlysensitivepoetisabletoexperiencethebeautyofordinary

life,capturehisownemotionsasthey30andisfinallyabletositinacalm,peacefulspacetousehis

imaginationtorecollecttheseemotionsandfinallywriteaboutthem.

Wordsworth3Jtothebeliefthatthe4treallanguageofmen^^ordinarydailylanguage—should

beusedtowritepoetry.However,Wordsworthrefinedthiscommonlanguagetoapurerformwithoutlosingthe

32ofitssimplicity.

TheEgotisticalSublime（個人崇高）isaconceptwhichsimplymeansthatapoet'sownsubjectiveviewof

truthandbeautyisextremely33tohiswork.Thepoemstheyproduceare34withtheir

ownimaginationandperspectiveonhowtheyperceivethingsaroundthem.Wordsworth'sworksareoftensaidto

beexamplesoftheEgotisticalSublimesincehisownexperienceofthingsiswhathebelievestobeeveryone's

experienceofthings.

Inconclusion,it'llbesafetosaythosemodern-daypoetswhoholdideaslikeself-expressionandsensitivityso

deartotheirheartstruly35ittoWordsworth'sworkstoreinforceideassosimpleyetsorevolutionary.

21.A.reduceB.relateC.extendD.restore

22.A.conflictB.touchC.cooperationD.proportion

23.A.overworkedB.overestimatedC.overweightD.overnight

24.A.IgnorantB.AwareC.TiredD.Reminded

25.A.inspirationB.contactC.heritageD.loneliness

26.A.perceptionB.qualificationC.concernD.projection

27.A.ThereforeB.HoweverC.SimilarlyD.Additionally28A.

contrastB.referenceC.responseD.parallel

29.A.defineB.dismissC.advertiseD.impose

30.A.ariseB.reflectC.composeD.release

31.A.belongedB.clungC.appealedD.headed

32.A.lackB.essenceC.obligationD.decoration

33.A.resistantB.attachedC.comparedD.relevant

34.A.restrictedB.burdenedC.coveredD.filled

35.A.shiftB.oweC.addD.channel

（B）

SincethestartoftheSpaceAge,private-sector（私營部門）leadershavebeenissuingwarningsthata

centralizedmodelwoulddamageprogressonpublicand,especially,commercialprioritiesinspace.Forexample,

RalphCordiner,theone-timeCEOofGeneralElectric,foresawmuchofthespacedevelopmentwhileforcefully

arguingthat,eventually,space's""developmentshallbeunderourtraditionalcompetitive36system.^^

Theeconomiclogicforthecentralizedmodelwasclear,andforseveraldecadesithas37itsgoals.

Publicgoodssuchasnationalsecurity,nationalpride,andbasicsciencearetypically38iflefttothe

market,andNASA（美國宇航局）wasfoundedtoprovidethemduringtheColdWar.Itscommand-and-control

structuregrewnaturallyfromthat39.

Underthismodel,theUnitedStateshasbeentheleadingspacepowerandNASAhasoccupiedthe

technologicalfrontier.ThesuccessoftheApollomissions,includingthe1969moonlanding,inspiredgrand

40ofwhatwouldcomenext.Intheearly1970s,studiesofspacecolonizationanddiversified

space-basedeconomies41.

ButafterthelastoftheApollomissionsin1972,NASA—andthustheUSspacesector—struggledtofinda

second42initsspacescript.PartofthereasonwasthatthetightconnectionbetweentheApolloprogram

andcompetitionwiththeSovietUnionmadeNASA'sbudgetvulnerable（脆弱的）tothesensethatthemissionhad

alreadybeenaccomplished.ApolloastronautBuzzAldrinsaid,"AftertheApollolunarmissions,Americalostits

loveofspace—therewasnoconcentrated43andwedidn'thaveanyclearobjectives”.

WhenNASAdecidedthatitsnextemphasiswouldbeontheSpaceTransportationSystem,betterknownas

theShuttle,itappliedlargelythesame44approachithadusedinthe1960s.Thefirstflightofthe

Columbiaspaceshuttlewasin1981.Successiveshuttleflightsenabledtwodecadesofachievements,includingthe

constructionoftheInternationalSpaceStation（ISS）andHubbleSpaceTelescope,which45American

technologicalcompetence.

Aftertwotragicaccidents,withtheChallengershuttlein1986andtheColumbiashuttlein2003,

momentum（勢頭）turnedawayfromtheShuttleandthecentralizedmodelofspaceit46.Theshuttle

programwascancelledin2011,leavingtheUnitedStatesinthe47positionofnotbeingabletolaunch

humansfromdomesticsoil.

Aninstructivecontrastisprovidedbythe48theUSgovernmenttooktothedevelopmentofthe

commercialsatellitemarket.In1962,CongresscreatedCOMSAT,afbr-profit,privatecorporationownedby

commonshareholdersandagroupoftelecommunicationscompanies.NASAwasofficiallychargedwithproviding

49advicetoCOMSAT,andtheagencywasgivenresponsibilityforCOMSAT'slaunches.Theidea

behindthispublic-private50wastoemploytheexpertiseofNASAtojump-startaprivate

communicationssatelliteindustry.Itledtotherapiddeploymentanduse—forbothpublicandprivatepurposes一

ofthevastrangeofsatellitesthatdominatethespaceeconomytoday.

36.A.enterpriseB.employmentC.electricityD.justice

37.A.draftedB.attainedC.recognizedD.estimated

38.A.underprovidedB.underfoundedC.overpricedD.overused

39.A.investmentB.acquisitionC.frictionD.objective

40.A.evolutionB.conversionsC.visionsD.industrialization

41.A.recoveredB.thrivedC.ceasedD.failed

42.A.actB.planetC.interpretationD.animation

43A.close-upB.warm-upC.follow-upD.dress-up

44.A.centralizedB.popularizedC.coinedD.mystified

45.A.stuffedB.admittedC.demonstratedD.overtook

46.A.accessedB.rejectedC.wrinkledD.represented

47.A.seniorB.navigableC.embarrassingD.harsh

48.A.riskB.routineC.approachD.advantage

49.A.legalB.technicalC.equalD.financial

50.A.partnershipB.debateC.meditationD.horizon

SectionB(22分)

Directions:Readthefollowingthreepassages.Eachpassageisfollowedbyseveralquestionsor

unfinishedstatements.ForeachofthemtherearefourchoicesmarkedA.B,CandD.Choose

theonethatfitsbestaccordingtotheinformationgiveninthepassageyouhavejustread.

(A)

Ifyou'vebeenthinkingaboutpursuingaBusinessManagementmajor,thenit'sprobablysafetoassumethe

businessworldappealstoyou.Butbeyondthatgeneralinterest,howcanyoutellifthisistherightcourseofstudy

foryou?Choosingamajororacademicprogramisaseriousdecision,andyou511wanttobesureyourchoicealigns

withyourpersonalityandyourvisionforyourcareer.

Unfortunately,unlessyouhavesupernaturalabilities,youcan'treallyknowfbrcertain.Butsolidresearchis

thenextbestthing.OnesolidstartingspotwouldbecheckingoutsomeofthecourseworkforBusiness

Managementmajorstoseewhatyourstudieswouldcover.Youcouldalsocheckoutmorecareerinformationabout

businessmanagementtogetanideaofpotentialoutcomes.Butifyouarestillonthefenceaboutifthismajorisa

goodchoicefbryou,thenyou'vecometotherightplace.

WeaskedexpertsinthefieldtoshareaboutthetraitsthatmattermostfbrthecareerandforBusiness

Managementstudents.Onethingthattheyallemphasizeistheabilitytobeagoodlistener.

Doyoutakethetimetoabsorbandprocesswhatthepeopleyouinteractwithareactuallysaying,insteadof

justwaitingfbryourturntotalk?Ifso,you'reontherighttrack.ObviouslyBusinessManagementstudentsneedto

understandavarietyofsubjectsastheyprogressintheiracademicprograms—andstronglisteningskillswillhelp.

Butthisabilitytoeffectivelylistenbecomesevenmorevaluablewhenappliedtoyourcareer.

''Managingismoreaboutlisteningthanitisabouttelling,saysDayneShuda,founderofGhostBlogWriters.

“That'sashiftinthinkingfbrmanypeople.Thebestmanagersknowthattheirjobistolistentotheirteamand

empowertheirteamtofindsolutions.^^Shudasaysgoodmanagementoftencomesdowntolistening,buttheskillis

rareintheworldtoday.

IsaBusinessManagementdegreeanaturalfitforyou?Ifyouareresonatingwithwhatissaidabove,you

couldreallythriveasaBusinessManagementmajor.Thiscareerpathcanleadyoutosomanydifferentoptionsand

settings,givingyoulotsofflexibilityandcontroloveryourownprogress.

Thenextstepistoresearchwhatenrollinginaprogramwouldinvolve.Howlongdoescompletingadegree

programtake?Whatwouldyoustudy?Togetacloserlookatthedetails,checkoutRasmussenCollege'sBusiness

Managementprogrampage.

51.Accordingtothefirstparagraph,whatistheauthor'sattitudetowardsthosewhoconsiderpursuingbusiness

managementmajor?

A.Positive.B.Doubtful.C.Cautious.D.Negative.

52.WhicharethethingsyoucandotomakesureaBusinessManagementmajorisrightforyou?①lblearnabout

thecoursesthatabusinessmanagementmajorstudentwouldtake

②Tocheckoutthecareerinformationaboutbusinessmanagement

(3)Toasktheexpertsforadviceabouttheimportantqualitiesinbusinessmanagement

④Tochoosecoursesthatwillhelpunderstandavarietyofsubjects

A.@@④.B.①③④.C.②③④.D.①②③.

53.Tobeagoodlistener,youshould.

A.waitpatientlyforyourturntotalkinaconversation.

B.thinkactivelyandeffectivelyaboutthewordsinaninteraction.

C.dominatetheconversationtoleadyourteammates.

D.alwaysremainsilentandonlylistentoothers.

54.Wherecanyoumostprobablyseethispassage?

A.Auniversity'swebpage.

B.Anacademicmagazine.

C.Amanagementtextbook.

D.Anonlineforumaboutmanagement.

(B)

ReviewsforTopGun2:Maverick

DowntonAbbeyII:ANewEra

9/106/104/10

Beautiful!MildTiredoffadingcharacters

cacaescherlMay2022guskeller21May2022Drabble5008May2022

Whatamasterpiece!I'maDowntonAbbey:ANewEraisIlovedtheDowntonAbbey

fanfromtheseriesandIsimpleescapism.Thescriptseriesandhavere-watched

mustadmitthatseeingtheemphasizesquantityoverthemduringlockdown.The

castalltogetherforallthesequality,paradingnumerousdelightfulfizzoftheearly

yearssohappyandcheerfultrivialplotlinesratherthanseriesgraduallybegantofade

isatrueblessingandwealldiggingintoanyparticularoutastheywentonbutthey

mustbesograteful.Iwentidea.Charactersarehollowlyheldusenrapturedbecause

totheMovieTheatertodaypleasantbecause,ultimately,wewereinvestedinthe

andeveryonewasenjoyingnothingisconsequential.Easycharacters.

somuch!PeoplewereentertainmenthasitsRollontheshowthroughtwo

alwayslaughingatMaggie'saudience,butsomeviewersmoviesandifsobviousthat

jokesandcommentingonmightwanttonalrange,boththecharactersandthe

eachscene...it'spurecharacterdepth,strongfranchisehaverunoutof

excitement.Ihavenowordsthemes,orsignificanttension.steam.Thisisaplotwhich

todescribemyloveforTheactingischarmingultimatelygoesprecisely

DowntonAbbey.enoughandthesoapyplotnowhere,sothatwe'releft

keepsmoving,butDowntonwithatripinthesouthof

AbbeyismoreofagetawayFrance(withoutthescenery)

thanajourney.andafilm-within-a-filmback

atthehouse.

55.Accordingtothecritics,whatmakesTopGun2:Maverickpraiseworthy?

A.Itoutshinesthepreviousmovieintermsofcharacterdepthandplotcomplexity.

B.Itprovidesinsightfulappreciationoflifeprogress.

C.Itlivesuptoaudience'sexpectations.

D.Itishonestaboutitsownshortcomings.

56.Theword"enraptured“mostprobablymeans.

A.disappointedB.furiousC.excitedD.responsible57.Whichofthefollowingstatementistrue?

A.JamesspeakshighlyoftheaudioandvisualeffectsofthenewTopGunmovie.

B.Bothguskeller21andCatalinalayemphasisonafilm'ssubstanceanddepth.

C.Drabble5008prefersthebigscreenadaptationstotheseries.

D.NeitherLouisanorcacaescherlpresentscommentsinabalanceway.

(C)

Earthisconstantlybeinghitbyspacerocks.Severaltonsraindownontheplaneteachdayintheformofdust.

Andlargerstrikeshavecreatedmorevisiblefeatures,includinggiantcraters.Butwhichofourplanet's

extraterrestrialscarsistheoldest?

ResearchersreportedonTuesdayinNatureCommunicationsthattheyhavepinpointedit,inWesternAustralia.

Itwascausedbyanimpactmorethan2.2billionyearsago.Interestingly,thattimingroughlycoincideswiththe

endofoneofourplanet'siceages.Animpactintheicewouldhaveliberatedanenormousamountofwatervapor,

theresearcherssuggest,perhapsenoughtoalterEarth'sclimate.

TheYarrabubbaimpactstructure,aboutaday'sdrivenortheastofPerth,isn'tmuchtolookattoday.The

originalcrater,believedtohavebeenroughly40milesindiameter,islonggone.That'sbecausethecombined

effectsofwind,rain,glaciationandplatetectonicshavewashedseveralmilesoffthesurfaceoftheplanet,

effectivelyerasingthecrater.Theextentoferosionsuggeststhattheimpactstructureisvery,veryold.

Existingcluesyield“aprettygiant“agerangeofaboutabillionandahalfyears,saidTimmonsErickson,a

geochronologistatNASAJohnsonSpaceCenterinHoustonandthestudy'sleadauthor.ButDr.Ericksonknew

thatitwaspossibletodofarbetter,byreadingthetinygeologicalclocksthathidewithinrocks.

In2014,Dr.Ericksoncollectedroughly200poundsofgraniticrocksfromYarrabubba.Backinthelaboratory,

basedonaseriesofexperiments,Dr.EricksonandhisteamcalculatedthattheYarrabubbaimpactoccurred2.229

billionyearsago,withanuncertaintyof5millionyears.Thenext-oldestimpactstructure,VredefortDomeinSouth

Africa,isover200millionyearsyounger.

TheageoftheYarrabubbaimpactstructurehappenstolineupwiththeendofaniceagewhichmakesfora

compellingcoincidence,Dr.Ericksonsaid:"Wouldanimpactev