哈工大考博英语真题以及答案.docx
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哈工大考博英语真题以及答案
GeneralEnglishAdmissionTestForNon-EnglishMajor
Ph.D.program
(HarbinInstituteofTechnology)
PassageOne
Questions1-7arebasedonthefollowingpassage:
Accordingtoarecenttheory,Archean-agegold-quartzveinsystemswereformedovertwobillionyearsagofrommagmaticfluidsthatoriginatedfrommoltengranitelikebodiesdeepbeneaththesurfaceoftheEarth.Thistheoryiscontrarytothewidelyheldviewthatthesystemsweredepositedfrommetamorphicfluids,thatis,fromfluidsthatformedduringthedehydrationofwetsedimentaryrocks.Therecentlydevelopedtheoryhasconsiderablepracticalimportance.MostofthegolddepositsdiscoveredduringtheoriginalgoldrusheswereexposedattheEarth’ssurfaceandwerefoundbecausetheyhadshedtrailsofalluvialgoldthatwereeasilytracedbysimpleprospectingmethods.Althoughthesesamemethodsstillleastoanoccasionaldiscovery,mostdepositsnotyetdiscoveredhavegoneundetectedbecausetheyareburiedandhavenosurfaceexpression.
Thechallengeinexplorationisthereforetounravelthesubsurfacegeologyofanareaandpinpointthepositionofburiedminerals.Methodswidelyusedtodayincludeanalysisofaerialimagesthatyieldabroadgeologicaloverview,geophysicaltechniquesthatprovidedataonthemagnetic,electrical,andmineralogicalpropertiesoftherocksbeinginvestigated,andsensitivechemicalteststhatareabletodetect:
thesubtlechemicalhalosthatoftenenvelopmineralization.However,noneofthesehigh-technologymethodsareofanyvalueifthesitestowhichtheyareappliedhavenevermineralized,andtomaximizethechancesofdiscoverytheexplorermustthereforepayparticularattentiontoselectingthegroundformationsmostlikelytobemineralized.Suchgroundselectionreliestovaryingdegreesonconceptualmodels,whichtakeintoaccounttheoreticalstudiesofrelevantfactors.
Thesemodelsareconstructedprimarilyfromempiricalobservationsofknownmineraldepositsandfromtheoriesofore-formingprocesses.Theexplorerusesthemodelstoidentifythosegeologicalfeaturesthatarecriticaltotheformationofthemineralizationbeingmodeled,andthentriestoselectareasforexplorationthatexhibitasmanyofthecriticalfeaturesaspossible.
1.Theauthorisprimarilyconcernedwith.
A.advocatingareturntoanoldermethodology.
B.explainingtheimportanceofarecenttheory.
C.enumeratingdifferencesbetweentwowidelyusedmethods
D.describingeventsleadingtoadiscovery
2.Accordingtopassage,thewidelyheldviewofArchean-agegold-quartzveinsystemsisthatsuchsystems
Awereformedfrommetamorphicfluids.
Boriginatedinmoltengranitelikebodies
Cwereformedfromalluvialdeposits
Dgenerallyhavesurfaceexpression
3.Thepassageimpliesthatwhichofthefollowingstepswouldbethefirstperformedbyexplorerswhowishtomaximizetheirchancesofdiscoveringgold?
ASurveyingseveralsitesknowntohavebeenformedmorethantwobillionyearsago.
BLimitingexplorationtositesknowntohavebeenformedformmetamorphicfluid.
CUsinganappropriateconceptualmodeltoselectasiteforfurtherexploration.
DUsinggeophysicalmethodstoanalyzerocksoverabroadarea.
4.Whichofthefollowingstatementsaboutdiscoveriesofgolddepositsissupportedbyinformationinthepassage?
AThenumberofgolddiscovermadeannuallyhasincreasedbetweenthetimeoftheoriginalgoldrushesandthepresent
BNewdiscoveriesofgolddepositsarelikelytobetheresultofexplorationtechniquesdesignedtolocateburiedmineralization
CItisunlikelythatnewlydiscoveredgolddepositswilleveryieldasmuchasdidthosedepositsdiscoveredduringtheoriginalgoldrushes.
DModernexplorersaredividedonthequestionoftheutilityofsimpleprospectingmethodsasasourceofnewdiscoveriesofgolddeposits.
5.Itcanbeinferredfromthepassagethatwhichofthefollowingiseasiesttodetect?
AAgold-quartzveinsystemoriginatinginmagmaticfluids.
BAgold-quartzveinsystemoriginatinginmetamorphicfluids.
CAgolddepositthatismixedwithgranite.
DAgolddepositthathasshedalluvialgold.
6.ThetheorymentionedinlineIrelatestotheconceptualmodelsdiscussedinthepassageinwhichofthefollowingways?
AItmayfurnishavalidaccountofore-formingprocesses,andhence,cansupportconceptualmodelsthathavegreatpracticalsignificance.
BItsuggeststhatcertaingeologicalformations,longbelievedtobemineralized,areinfactmineralizedthusconfirmingcurrentconceptualmodels.
C.ItsuggeststhattheremaynotbeenoughsimilarityacrossArchean-agegold-quartzveinsystemstowarranttheformulationofconceptualmodels.
DItcorrectsexistingtheoriesaboutthechemicalhalosofgolddeposits,andthusprovidesabasisforcorrectingcurrentconceptualmodels.
7.Accordingtothepassagemethodsofexploringforgoldthatarewidelyusedtodayarebasedonwhichofthefollowingfacts?
AMostoftheEarth’sremaininggolddepositsarestillmolten.
BMostoftheEarth’sremaininggolddepositsareexposedatthesurface.
CMostoftheEarth’sremaininggolddepositsareburiedandhavenosurfaceexpression
DOnlyonetypeofgolddepositwarrantsexploration.sincetheothertypesofgolddepositsarefoundinregionsdifficulttoreach
PassageTwo
Questions8-15arebasedonthefollowingpassage:
Inchoosingamethodfordeterminingclimaticconditionsthatexistedinthepast,paleoclimatologistsinvokefourprincipalcriteria.First,thematerial—rocks,lakes,vegetation,etc.—onwhichthemethodreliesmustbewidespreadenoughtoprovideplentyofinformation,sinceanalysisofmaterialthatisrarelyencounteredwillnotpermitcorrelationwithotherregionsorwithotherperiodsofgeologicalhistory.Secondintheprocessofformation,thematerialmusthavereceivedanenvironmentalsignalthatreflectsachangeinclimateandthatcanbedecipheredbymodernphysicalorchemicalmeans.Third,atleastsomeofthematerialmusthaveretainedthesignalunaffectedbysubsequentchangesintheenvironment.Fourth,itmustbepossibletodeterminethetimeatwhichtheinferredclimaticconditionsheld.Thislastcriterionismoreeasilymetindatingmarinesediments,becausedatingofonlyasmallnumberoflayersinamarinesequenceallowstheageofotherlayerstobeestimatedfairlyreliablybyextrapolationandinterpolation.Bycontrast,becausesedimentationismuchlesscontinuousincontinentalregions,estimatingtheageofacontinentalbedfromtheknownagesofbedsaboveandbelowismorerisky.
Oneveryoldmethodusedintheinvestigationofpastclimaticconditionsinvolvesthemeasurementofwaterlevelsinancientlakes.Intemperateregions,thereareenoughlakesforcorrelationsbetweenthemtogiveusatenablepicture.Inaridandsemiaridregions,ontheotherhand,thesmallnumberoflakesandthegreatdistancesbetweenthemreducethepossibilitiesforcorrelation.Moreover,sincelakelevelsarecontrolledbyratesofevaporationaswellasbyprecipitation,theinterpretationofsuchlevelsisambiguous.Forinstance,thefactthatlakelevelsinthesemiaridsouthwesternUnitedStatesappeartohavebeenhigherduringthelasticeagethantheyarenowwasatonetimeattributedtoincreasedprecipitation.Onthebasisofsnowlineelevations,however,ithasbeenconcludedthattheclimatethenwasnotnecessarilywetterthanitisnow,butratherthatbothsummersandwinterswerecooler,resultinginreducedevaporation
Anotherproblematicmethodistoreconstructformerclimatesonthebasisofpollenprofiles.Thetypeofvegetationinaspecificregionisdeterminedbyidentifyingandcountingthevariouspollengrainsfoundthere.Althoughtherelationshipbetweenvegetationandclimateisnotasdirectastherelationshipbetweenclimateandlakelevels,themethodoftenworkswellinthetemperatezones.Inaridandsemiaridregionsinwhichthereisnotmuchvegetation,however,smallchangesinoneorafewplanttypescanchangethepicturetraumatically,makingaccuratecorrelationsbetweenneighboringareasdifficulttoobtain.
8.Whichofthefollowingstatementsaboutthedifferencebetweenmarineandcontinentalsedimentationissupportedbyinformationinthepassage?
A.Dataprovidedbydatingmarinesedimentationismoreconsistentwithresearchers’findingsinotherdisciplinesthanisdataprovidedbydatingcontinentalsedimentation.
B.Itiseasiertoestimatetheageofalayerinasequenceofcontinentalsedimentationthanitistoestimatetheageofalayerinasequenceofmarinesedimentation.
C.Marinesedimentationismuchlesswidespreadthancontinentalsedimentation
D.Marinesedimentationismuchmorecontinuousthaniscontinentalsedimentation.
9.Whichofthefollowingstatementsbestdescribestheorganizationofthepassageasawhole?
A.Theauthordescribesamethodfordeterminingpastclimaticconditionsandthenoffersspecificexamplesofsituationsinwhichithasbeenused.
B.Theauthordiscussesthemethodofdatingmarineandcontinentalsequencesandthenexplainshowdatingismoredifficultwithlakelevelsthanwithpollenprofiles.
C.Theauthordescribesthecommonrequirementsofmethodsfordeterminingpastclimaticconditionsandthendiscussesexamplesofsuchmethods.
D.Theauthordescribesvariouswaysofchoosingamaterialfordeterminingpastclimaticconditionsandthendiscusseshowtwosuchmethodshaveyieldedcontradictorydata.
10.Itcanbeinferredfromthepassagethatpaleoclimatologistshaveconcludedwhichofthefollowingonthebasisoftheirstudyofsnow-lineelevationsinthesouthwest6ernUnitedS