×
Log in to StudySoup
Get Full Access to Probability And Statistics For Engineering And The Sciences - 9 Edition - Chapter 10.1 - Problem 4
Join StudySoup for FREE
Get Full Access to Probability And Statistics For Engineering And The Sciences - 9 Edition - Chapter 10.1 - Problem 4

Already have an account? Login here
×
Reset your password

It is common practice in many countries to destroy(shred) refrigerators at the end of

Probability and Statistics for Engineering and the Sciences | 9th Edition | ISBN: 9781305251809 | Authors: Jay L. Devore ISBN: 9781305251809 122

Solution for problem 4 Chapter 10.1

Probability and Statistics for Engineering and the Sciences | 9th Edition

  • Textbook Solutions
  • 2901 Step-by-step solutions solved by professors and subject experts
  • Get 24/7 help from StudySoup virtual teaching assistants
Probability and Statistics for Engineering and the Sciences | 9th Edition | ISBN: 9781305251809 | Authors: Jay L. Devore

Probability and Statistics for Engineering and the Sciences | 9th Edition

4 5 1 343 Reviews
19
1
Problem 4

It is common practice in many countries to destroy(shred) refrigerators at the end of their useful lives. Inthis process material from insulating foam may bereleased into the atmosphere. The article Release ofFluorocarbons from Insulation Foam in HomeAppliances During Shredding (J. of the Air andWaste Mgmt. Assoc., 2007: 14521460) gave the followingdata on foam density (g/L) for each of two refrigeratorsproduced by four different manufacturers:1. 30.4, 29.2 2. 27.7, 27.13. 27.1, 24.8 4. 25.5, 28.8Does it appear that true average foam density is not thesame for all these manufacturers? Carry out an appropriatetest of hypotheses by obtaining as much P-value informationas possible, and summarize your analysis in anANOVA table

Step-by-Step Solution:
Step 1 of 3

Chapter13| 1 LearningObjectives 1. Describethetheoryofplatetectonicsandtheevidencesupportingtheconceptofcontinental drift. 2. Explainthevarioustypesofplatemovementsthatoccurasaresultofcontinentaldrift. 3. Discusshowplateconvergencepromotes foldingofrock,resultingintheformationofanticlines, synclines,andotherstructuralfeatures. 4. ExplainthegeneraldevelopmentoftheAppalachianMountainsandwhysegmentsoftheRidge andValleyProvincemaybestructurallymorecomplexthantheya ppear. 5. CompareandcontrastthevariouskindsoffaultsthatoccuronEarth. 6. Describewhyearthquakesoccur,thevariousfeaturesassociatedwiththem,andhowtheir locationcanbepreciselydetermined. 7. Compareandcontrastthevarioustypesofvolcanoes andwhytheyoccur. 8. DiscussthePacificRingofFireandexplainthegeographyoftheCascadeVolcanicArc. PlateTectonics :thetheorythattheEarth’scrustisdividedintoanumberofplatesthatmove becausetheyfloatontheasthenosphere. TheLithosphericPlates th Intheearly20 century,aGermangeophysicistnamedAlfredWegenernoticedthatmanyofthe continentslookasiftheycouldhavefittogetheratonetimeasonesinglelandmass. • Afterfurtherinvestigation,Wegenerdiscoveredthatportio nsofsomecontinentssharethe samekindofrocksandfossilswithothercontinents. • Asaresult,Wegenerproposedin1915thatasupercontinentexistedabout300milliony ears agothathenamedPangaea(meaningwholeearth). Comment [KL1]: Thehypotheticalsupercontinent, composedofallthepresentcontinents,thatexisted between300and200millionyearsago. • Hearguedthatthecontinentshaddriftedpartinaprocesshecalled continentaldrift. Comment [KL2]: Thetheorythatthecontinentsmove relativetooneanotherinassociationwithplatetectonics. Chapter13| 2 Wegener’sideaswerecompletelycontradictorytothecurrentbeliefsinthegeologiccommunityand werelargelyignoreduntilthe1950s,whenstudiesbeganoftheo ceanbasinsaroundtheworld.Atthe sametime,geologistsbegantoinvestigatethecauseofearthquakesmoreclosely. • ThecombinedstudiesprovedthattheEarth’scrustconsistsofaseriesofinterconnectedplates thatindeedmoverelativetooneanother,whichformedthefoundationforthetheoryofplate tectonicsthatemergedinthe1960s. • Thetheorywasrevolutionarybecauseitexplainedagreatdealofvolcanicandearthquake activityonEarth. • ItalsovalidatedWegener’sbasicpremiseofcontinentaldriftbecauseitprovidedthe mechanismthatwouldmakethemigrationpossible. Thesevenmajorplates(boldfacetype)cover94%ofEarth.Aboutadozensmallerplatescoverthe remaining6%ofEarth.Noticethewaythattheplatesmove(arrows)relativetooneanother. [TheboundarybetweentheIndianandAustralianplatesisuncertain;manysourcesreferinsteadtothe “Indo-Australian”plate.] PlateMovement Thenextobviousquestionis whycontinentaldriftoccurs.Atafundamentallevel,ithappensbecause tectonicplatesfloatontheasthenosphereandaremovedbyconvectionloopsdrivenby geothermal activity. • ConvectionwithinEarthoccursbecausetheradioactivedecayofelements,such asuranium, deepwithintheEarthcreatesveryhightemperaturesbetween1000 -2000°C(1800-3600°F). Thesehightemperaturescauseplumesofmagmatoriseslowlybyconvectionwithinthemantleand intotheasthenosphere.Asthesemagmaplumesreachtheba seofthecrust,thespreadhorizontally andcool,movingsegmentsofthecrustintheprocess.Rockcreatedasthemagmacoolssinksbackinto themantle,whereitmeltsagain. HowdoweknowplatesaremovingEvidenceofplatemovementappearsintheag eoftheseafloor. • Convectioninthemantlebringsmagmaupthroughfracturesinthecrust,whereitextrudes ontotheseafloor,cools,andformsnewoceaniccrust. • Thefigurebelowshowsisochron es(linesofequalage)fortheoceanfloorsaroundtheworld andclearlyindicatesareaswhereoceanicplateshavebeenspreadingapart. Chapter13| 3 Inthismap,colorsareassociatedwithseafloorsandthecontinents aregray.Theyoungestseafloorrocks(inred)occurinthezonesof seafloorspreading,withprogressivelyolderrocks(yellows,greens, andblues,respectively)awayfromtheseregions. Anadditionalpieceofevidencesupportingthetheoryofcontinentaldriftisthatmagneticstripes run paralleltotheMid-AtlanticRidgeacrosstheseafloorinasimilarpatterntotheisochronesshowninthe figureabove. • ThesestripesreflectthefactthattheEarth’smagneticfieldhasperiodicallyreversedthrough time,withmagneticnorthbecomingsouthandviceversa. • Theoceanfloorcontainsarecordofmagneticreversalsbecause,asthenewseaflooris progressivelycreated,itsmagneticorientationisalignedwiththedirectionatthattime. TypesofPlateMovements Therangeofpotentialplatemovementsincludes(1)movingawayfromeachother,(2)slidingpasteach other,and(3)collidingheadon. PassiveMargins Comment [KL3]: Aplacewherethecontinentalcrustand Thesimplestkindoftectonicinteractionoccursatpassivemargins. theoceaniccrustareonthesametectonicplateandthus don’tmoverelativetoeachother. • Theseregionsfrequentlyoccurinplaceswhere thecontinentalcrustandtheborderingoceanic crustareactuallyonthesametectonicplate. • OneexampleistheeasternseaboardofN.America,whichhasapassivemarginwiththe oceaniccrustinthewesternpartoftheAtlanticOceanbasin.Althoughth econtinentalcrust thatformstheN.Americanlandmassisaseparaterockbodyfromtheadjoiningoceaniccrust, theyarebothpartoftheN.Americanplate. TransformPlateMargins Comment [KL4]: Aplateboundarywhereopposingplates Transformboundariesareplaceswhereplatesslidehorizontallypast eachother. movehorizontallyrelativetoeachother. Chapter13| 4 Atthesemargins,theplaneofmotionisalonganearlyverticalbreak(orfault)thatextendsthrough muchofthelithosphere. • ExamplesaretheSanAndreasFaultinCaliforniaandtheDeadSeaFaultalong theborderof IsraelandJordan. PlateDivergence Insomeplaces,lithosphericplatesmoveawayfromeachotherinaprocesscalled platedivergence.This typeofmovementoccursinregionswhererisingmagmaplumeswithinEarthmoveupwardand outwardbetweenplatefractures,spreadingEar th’splatesapartinaprocesscalled rifting(or Comment [KL5]: ThespreadingapartoftheEarth’scrust divergence). bymagmarisingbetweenfracturesintheEarth’splates. • Agreatplacetoseeriftingisontheseafloorwheremagmaproducesaridge -likefeaturecalleda mid-oceanicridge,whichliesparalleltotheriftzone. Comment [KL6]: Aridge-likefeaturethatdevelopsalonga riftzoneintheoceanduetomagmaupwelling. Platescanalsodivergewithincontinents,causingagradualsplitinthelandmasstooccur.Oneofthe best-knownexamplesisineasternAfricawheretheEastAfricanRiftislocated.Continentalriftinginthis areahasproducedadistinctvalley landscapeborderedbysteepcanyonwalls,aswellasseverallarge lakes.Inthenorthernpartoftheriftzone,platedivergenceisoccurringinthreeplacesthatmergeata singleplaceknownasatriplejunction. • Twooftheriftsareoceanic,withoneopening theRedSeaandtheothercausingenlargementof theGulfofAdenonthesouthernsideofSaudiArabia. Chapter13| 5 • Thelastrift,whichisonland,extendssouthfromthejunctureoftheRedSeaandtheGulfof Aden.TheeasternpartoftheAfricancontinentisslowl ysplittingintwo,resultinginseveral largelakessuchasLakeVictoria. PlateConvergence Plateconvergenceoccursinthreegeneralsettings:(1)oce aniccrusttocontinentalcrust ,(2)oceanic crusttooceaniccrust,and(3)continentalcrusttocont inentalcrust. (1) OceanicCrusttoContinentalCrust Oceaniccrustisgenerallydenserthancontinentalcrustbecauseoceaniccrustconsistsofbasalticrock, whereascontinentalcrusttendstobegranitic.Inconvergencezoneslikethis,theoceaniccrusts inks beneaththelightercontinentalcrustinaprocesscalled subduction. Comment [KL7]: Theprocessbywhichonelithospheric • Subductionisinitiatedwhenoceanicplatesdivergeduetoseafloorspreading.Asthespreading plateisforcedbeneathanother. forcesslowlymoveawayhorizontallyfromthespreadingzoneandtowardcontinenta lmargins. • Whentheoceaniccrustconvergeswiththecontinentalcrust,thedenseroceaniccrustisforced beneaththecontinentalcrustanddownintotheuppermantle.Astheslabisforceddeeper,the internaltemperaturegraduallyincreasesinadistin ctgeothermalgradient. • Whentheoceaniccrusthitstheuppermantle,itmeltsandisrecycledintomagmaaspartofthe rockcycle. Thisprocessisnotcontinuous,butinsteadisepisodic.Theoceanicplatedoesn’tflowsmoothlybeneath thecontinentalcrust.Itmovesonlywhenthebuildupofstressbehindit –causedbyseafloorspreading –ismorethanthefrictioncausedbyslidingunderneaththecontinentalplate. • Thestresscancauseearthquakesandsignificantdeformationoftherocks abovethesubduction zone.Thiscanalsoresultintheconstructionofmountainrangesandtheformationofvolcanoes wheremagmaworksitswaytothesurface. Chapter13| 6 (2) OceanicCrusttoOceanicCrust Whentwobodiesofoceaniccrustcollidewithoneanother,onep latewilltypicallybesubducted beneathanother(eventhoughtheyaresimilardensities),formingan oceanictrench.Thissubduction willcausestresstotheoverridingseafloorthatmaycauseittocrumpleupwardintomountainsbelow theoceansurface. • Moreoften,thesubductionwillresultintheformationofvolcanoes(duetomeltingofthecrust intheuppermantle)thatgrowupwardinthewater. Ifthevolcanoesgrowenough,theywill breachthesurfacetoformdistinctiveislandchains. (3) ContinentalCrusttoContinentalCrust Whentwocontinentalcrustscollide,oneplatedoesnotrideoverorbelowtheother.Instead,they smashtogetherliketwocarsinahead -oncollision.Thecrust,likethecars,crumples,causingfoldingof theformerlyhorizontalbedrockthroughcompression. Youcanseeevidenceofpastcompressionandfoldingbylookingatthe rockstructure.Ingeneral,a Comment [KL8]: Theinternalarrangementofrocklayers. closecorrelationexistsbetweentheamountofcompressionandthenatureofthefold. • Amonoclineisaone-sidedslopewherebedsofhorizontalrockareinclinedinasingledirection Comment [KL9]: Ageologiclandforminwhichrockbeds overalargearea.Thekindoffoldoccurswhentheamountofcompressionisrelativelylow. areinclinedinasingledirectionoveralargedistance. Moreextensivecompressioncausesanticlinesandsynclinestoform. • Ananticlineisaportionofthefoldwheretherocklayersarcupwardtoformaconcavearch Comment [KL10]: Aconvexfoldinrockinwhichrock alongthefoldaxis.One-halfofsuchafoldiscalleda limb. layersarebentupwardintoanarch. • Asynclineistheportionofthefoldwheretherocklayersdipdownwardtoformaconvex Comment [KL11]: Aconcavefoldinrockinwhichrock trough. layersarebentdownwardtoformatrough. • Ifthecollisionisespeciallyintense,therockscanbefoldedsomuchthatan overturnedfold(or Comment [KL12]: Astructuralfeatureinwhichthefold limbistiltedbeyondvertical,whichresultsinbothlimbs recumbentfold)forms. inclinedinthesamedirection,butnotatthesameangle. • Stillmorecompressionresultsinan overthrustfold,whichoccurswhenonepartoftherock Comment [KL13]: Astructuralfeaturewhereonepartof massisshovedupandovertheother. therockmassisshovedupandovertheother. GeomorphologyandtheEvolutionoftheAppalachianMountains Large-scalecompressionofrocksisfrequentlyassociatedwiththeformationofmountains.Thestudyof mountainformation,aswellastheshapeoftheEarth’ssurfaceingeneral,fallswithinthesubd iscipline ofphysicalgeographycalled geomorphology. Comment [KL14]: Thebranchofphysicalgeographythat investigatestheformandevolutionoftheEarth’ssurface. • Geomorphologyisthestudyoftheformation,shape,spatialdistribution,andevolutionof landformsonEarth–thus,thenamegeo(Earth)morphology(shape). • Incontrasttoalandscape,whichistheoverallappearanceofaplaceintermsofitsvegetation topography,orhumanmodifications,a landformisadistinctgeographicfeature,suchasa Comment [KL15]: Anaturalfeature,suchasahillor mountain,rivervalley,coastline,orsanddune,forexample. valley,onthesurfaceofEarth. • Thestudyofgeomorphologyisrooted deeplyingeologybecauseitrequiresathorough understandingofhowsedimentsareeroded,transported,anddeposited. Asfarasthegrowthofmountainsisconcerned,theytypicallyformduringadistinctintervaloftime calledanorogeny.Therearemanyexcellentexamplesofhowcontinentalcollisionandcompression Comment [KL16]: Aperiodofmountainbuilding,suchas theAlleghenyOrogeny. causeorogeniesinwhichrocksareintenselyfolded. Chapter13| 7 • TheAppalachianMountainsareanexcellentexample,extendingapproximately2500km(~1600 mi)alongtheeasternUnitedStates.Severa lphasesofmountainbuildingoccurredinthisregion, includingtheTaconicOrogeny(~450millionyearsago),AcadianOrogeny(~375millionyears ago),andAlleghenyOrogeny(~290to248millionyearsago). Hogbackridge:aridgeunderlainbygentlytippedrockstratawithalong,gradualslopeononesideand arelativelysteepscarporcliffonanother. • Theridgesoneachsideofthevalleyareremnantsofthelimbsoftheanticline.Sucharidgeis calledahogbackridgebecauseonesideoftheridgeis steeperthantheother. Anticlinalvalley:atopographicvalleythatoccursalongtheaxisofastructuralanticline. Synclinalvalley:atopographicvalleythatoccursalongtheaxisofastructuralsyncline. Asynclinalvalleyliesimmediatelytotheri ghtofthehogbackridge-and-valleynetworkatpointAandis whatyouwouldexpectsinceitliesbelowtheadjacentridge. (a) Thelandscapeshortlyafterfolding.Anticlinesformthehighgroundground,whereas valleysoccurinsynclines. (b) Astimeprogresses,erosionmodifiesthelandscape.AnticlinesAandBareerodedby streams,formingvalleysinupward-archingstructures.Hogbackridgesexistonbothsides oftheanticlinalvalleyat A,wherelimbsoftheformeranticlineformthehighground.To therightatpointB,extensiveerosionhasinvertedthetopographysothattheridgeis underlainbyasyncline. Chapter13| 8 KeyConceptstoRememberAboutPlateTectonics 1. TheEarth’scrustismadeupofinterconnectedplates. 2. Avarietyofevidence,includingfossil locationsandmeasurementofmotion,stronglysupports thetheoryofcontinentaldrift. 3. Platemarginscanbepassive,transform,converging,ordiverging. 4. Atdivergingplatemargins,magmaplumesfromtheasthenospherecausingrifting,eitheron continentsorontheseafloor. 5. Atconvergingplatemargins,platescollideorsubductinavarietyofsettings,causing geomorphicfeaturessuchasalpinechainsandvolcanoes. Earthquakes: shakingoftheEarth’ssurfaceduetotheinstantaneousreleaseofaccumula tedstress alongafaultplaneorfromundergroundmovementswithinavolcano. Anearthquakeoccurswhenthethesuddenreleaseofaccumulatedtectonicstressisreleasedinan instantaneousmovementoftheEarth’scrust.Althoughthistypeofmovementis associatedwithplate boundaries,itcanalsooccurduetorapidmovementofmagmawithinavolcano. • Thestrongestearthquakesareusuallymostassociatedwithplateboundariesbecausestress buildsastheplatesgrindtogether. • Thisstresscreatesafra cturebetweenadjoiningplatescalleda fault.Atsomelocations,faults Comment [KL17]: AcrackintheEarth’scrustthatresults extenddeeplyintotheEarth’scrust,whereasatotherplacestheyareveryshallow. inthedisplacementofonelithosphericplateorrockbody relativetoanother. • Faultsandearthquakescanalsooccurinthemiddleofplatesbutitismuchlesscommon. • Althoughmostlargeearthquakesoccuronmajorplateboundaries,smallerearthquakescan occurwhereverasmallfaultoccursinarockbody. Theimportantthingtorememberisthattheplatesdon’tgraduallyslidebyeachother.Theyarelocked byfrictionforlongperiodsoftime,causingthestresstobuild. • Thestressbuildstoacriticalpointwhenaruptureoccursalongthefaultplaneandthestressis releasedanalogoustothestressreleasedwhenastretchrubberbandiscut. Therocklayerson eithersideofthefaultimmediatelyadjust. • Theplacewithinthelithospherewherethefaultbreaksiscalledthe focusandusuallyoccursa fewkilometersdeepwithintheground. • Thepointonthesurfacedirectlyabovethefocusisknownasthe epicenter. LocatingtheEpicenter Whenanearthquakeoccurs,thefirstgoalofgeologistsistodeterminethelocationoftheepicenter. Thisisaccomplishedthroughaprocessoftriangulation,duringwhichthedistancetotheepicenteris comparedamongseismographsstationedatthreeseparatelocations. • Thismethodologyisbasedoffthefactthatearthquakesproducetwokindsofseismicwaves,or bodywaves,thatradiatethroughtheEarth’sinterior,Pwaves(orprimarywaves)andSwaves (orsecondarywaves). • Thesetwotypesofwavesmoveindifferentwaysandtravelatdifferentspeeds. Chapter13| 9 • PwavesarecompressionalwavesthatcausetheEarth’scrusttoexpandandcontractrapidlyin ahorizontalmannerasthewavesradiateoutfromth eepicenter,andtypicallymoveatabout 1.5-8km/s(~1-5mi/s)throughthecrust. • Swavesmoveabout60-70%slowerandmoveinaverticalfashionsimilartothewavepulseina ropewhenyouwhipitupanddown.Theycausethegroundtovibrateinarollingfashionthat canbequitenoticeableandscary. • Themagnitudeofthesewavesismeasuredatanobservationstationwithaseismograph. MeasuringEarthquakeMagnitude Thestrengthofanearthquakeismeasuredonthe Richterscale,whichisrelatedtotheamplitudeofthe Comment [KL18]: Thelogarithmicscaleusedtomeasure seismicwavesmovingthroughtheEarth’scrustasdeterminedbytheseismograph. thestrengthofanearthquake. Thesecubesshowthelogarithmicnatureofthe Richterscale,withthesizeofeachcuberepresenting power.Forexample,amagnitude2earthquakeIs10 timesstrongerthanamagnitude1earthquake,and amagnitude3earthquakeis100timesstrongerthan amagnitude1earthquake. Chapter13| 10 TypesofFaults EarthquakesalsocausedeformationoftherocksbothwithinthecrustandonEarth’ssurface.This deformationisusuallya ssociatedwithdifferenttypesoffaultsthatoccurwhenopposingrockbodies moverelativetooneanother inassociationwithplatetectonics. (a) NormalFault Comment [KL19]: Asteeplyinclinedfaultinwhichthe hangingrockblockmovesrelativelydownward. Onetypeoffaultisanormal fault,whichisaverticalfaultinwhichoneslaboftherockisdisplacedup andtheotherslabdown.Wheresuchfaultsoccur,theopposingblockspullawayfromoneanotherby gravity,whichcausesoneofthefaultblockstoslipuprelativetothefaultplane asanupthrownblock (calledahorst),whiletheotherslipsdownasadownthrownblock(calleda graben).Theexposedside Comment [KL20]: Anupthrownblockofrockthatlies betweentwosteeplyinclinedfaultblocks. oftheupthrownrockformsacliff -likefeatureknownasafaultescarpment(orscarpforshort). (b) ReverseFault Comment [KL21]: Adownthrownblockofrockthatlies betweentwosteeplyinclinedfaultblocks. Anotherkindoffaultisareversefault,whichlooksverysimilartothenormalfaultbuthasadifferent Comment [KL22]: Astep-likefeatureontheEarth’s causeandnatureofmovement.Whereasthenormalfaultentailsmovementofblocks awayfromeach surfacecreatedbyfaultslippage. other,areversefaultresultswhenblocksmove towardeachother,causingonetorideupsteeplyover Comment [KL23]: Asteeplyinclinedfaultinwhichthe theother. hangingrockblockmovesrelativelyupward. (c) Strike-SlipFault Comment [KL24]: Astructuralfaultalongwhichtwo Thestrike-slipfaultentailspurelyhorizontalmovementofthetwoplatespasteachother.Strike -slip lithosphericplatesorrockblocksmovehorizontallyin oppositedirectionsandparalleltothefaultline. faultsandtransformfaultsarecloselyrelatedbecausetheysharethesame kindsofhorizontal movement.Theprimarydifferencebetweentransformandstrike -slipfaultsisthattransformfaultsare associatedwithlarge,tectonicplateboundaries,whereasstrike -slipfaultsoccurwheresmallrockblocks movehorizontallyrelative tooneanother. (d) OverthrustFault Overthrustfaultsoccurwhenonerockbodyisthrustupandoveranother,usually inassociationwith folding.Thesefaultsdifferfromnormalandreversefaultsbecausetheirfaultplanesareusuallyata shallowerangleincomparison. Chapter13| 11 Volcanoes: amountainorlargehillcontainingaconduitthatextendsdownintotheuppermantle, throughwhichmagma,ash,andgasesareperiodicallyejectedontothesurfaceofEarthorintothe atmosphere. Inmostcasesvolcanoesareinactiveforsometimeanderuptonlywhenthepressureofmaterialrising fromthemantlebecomesexcessive.Thel engthofinactivityvariesdramaticallybetweenvolcanoes. Somevolcanoesliedormantforhundredsorthousandsofyearsbeforetheyerupt,whereasothersare inanear-constantstateoferuption. ExplosiveVolcanoes Anexplosivevolcanoisonethaterupt sveryquicklyandwithgreatforce.Theeasiestkindtounderstand isacinder-conevolcano,whichusuallyformsveryquicklyafterasingleeruption.Thesevolcanoesare smallrelativetoothertypesofvolcanoes,havesteepsides(~30 °),andconsistofsolidifiedmagma fragments,rockdebris,andashthatareejectedfromacentralvent. MountCapulinhaseruptedonlyonce,about62,000yearsago,is approximately300m(1000ft)high,andisatypicalcinder -cone volcano. Incontrasttocinder-conevolcanoes,compositevolcanoesarevolcanoesthatbuildupandgrow over thecourseofseveraleruptions.Theyaretypicallyinactiveforlongperiodsoftimebetweeneruptions, butwhentheydoerupt,theytendtodosoquite violently. • Suchaneruptionoccursbecausethemagmawithincompositevolcanoesisrichinsilicasand thereforehighlyviscous(stickandslowflowing).Asaresult,gasesaregraduallytrappedinthe magmaduringtheinactivephaseandbuilduppressure insidevolcanountilitexplodes. • Theeruptionsendsvolcanicashhighintotheatmosphereandthicklayersofvolcanicdebriswill accumulateontheslopesofthevolcano,causingittoenlarge.Thismayconsistofalternating layersoflava(magmaflowingonthesurface)andfragmentedrockdebriscalled pyroclastic material(ortephra),suchasvolcanicash,cinders,andboulders. • Alsocalledstratovolcanoesbecauseofthelayersofvolcanicdebris,thesevolcanoestypically havemoderatelysteepconesw ithasemi-horizontaltopcontainingacrater.Theyaremuch largerthancindercones,perhapsover3000m(10,000ft)high. Chapter13| 12 Sometimestheeruptionofacompositevolcanoissoexplosivethatitliterallyblowsthetopoffthe mountain,creatingalarge crater.Afterthismassivekindoferuption,thecratermaypartiallyfillwitha lavadome.Whilethesefeaturesometimesoccuraloneandareclassifiedasaparticulartypeofvolcano Comment [KL25]: Asteep-sidedvolcaniclandform bymanygeologists,themajorityoftherecentlyactivelylavadom esoccurinassociationwithcomposite consistingofhighlyviscouslavathatdoesnotflowfarfrom itspointoforiginbeforeitsolidifies. volcanoes. VolcanicArcsatPlateBoundaries Compositevolcanoesaremostcommonlyassociatedwithplateboundariesinplaceswheresubduction isoccurring.Giventhatsubductiontendstooccuralongthelengthofce rtainplateboundaries,these zonesareplaceswhereachainofvolcanoesistypicallylocatedatthesurface.Suchachainiscalleda volcanicarc.Awell-knowntectonicfeatureassociatedwithanumberofvolcanicarcisthe PacificRing Comment [KL26]: Achainofvolcanoescreatedbyrising ofFirewhichfollowsmoreoftheoutlineofthePacificplate. magmaderivedfromasubductingtectonicplate. Chapter13| 13 FluidVolcanoes Inadditiontothevolcanoesthateruptexplosively,anumberofpromin entvolcanoeshaveveryfluid eruptionswithflowingriversoflava. • Themagmathatresultsinfluideruptionscontainsfarlesssilicaandisthuslessviscous. • Asaresult,thelavaassociatedwithsuchaneruptionflowsacrossthesurfaceuntilitcoolsto frombasalt. • Sucheruptionscanoccurforweek sandmonthsatatimeandgenerallytak eplacemore frequentlythanexplosiveeruptions Althoughfluideruptionsare occasionallyassociatedwithcompositevolcanoes,theyusuallyresultinthe formationofashieldvolcanothathasshallowslopingsides. • Thistypeofvolcanodevelopsbecausesuccessiveeruptionsoffluidmagma causethevolcanoto buildupwardgraduallyoveramuc hbroaderareathancompositevolcanoes. • Anumberofprominentshield volcanoesoccuronEarthinassociationwithsubductionzones andriftzones. Hotspots Insomecases,avolcanoisassociatedwithastationaryzoneintheasthenospherewhereupwelling magmafromamantleplumeisr eleasedatthesurface.Suchageologicalfeatureiscalleda hotspot. • Althoughhotspotsoccurmore randomlythansubductionandriftzones,theyareassociated withsomeofthemostintensivevolcanicactivityonthepl anet.Theseeruptionscanbeofeither fluidorexplosivenature. Anexampleoffluideruptions associatedwithahotspotcanbeseeninthestateofHawaii,whichliesin themiddleofthePacifictectonicplatewherethe Hawaiianhotspotoccurs. • Thishotspotisreleasinghighlyfluidmagmathathasbuiltavarietyofshield volcanoesonthe island,suchaMaunaLoa. • MaunaLoaisthelargestvolcanoonEarthandisoneofthe fivethatcollectivelycomprisethe island. Chapter13| 14 • Evidenceindicatesthatthe Hawaiianhotspothasbeenactiveforalongtime.Thepicturebelow showsatrailofislandsandsub mergedhighlandscalledseamountsthatextendtothenorthwest fromtheislandofHawaii. AnexampleofanexplosivevolcaniceruptionistheYellowstonehotspot,whichliesbene ath YellowstoneNationalParkinnorthwe stWyoming. • SimilartotheHawaiianhotspot,theYellowstoneho tspotisafixedzoneofupwellingmagma. • Inthiscase,thehotspotliesbeneaththeNorthAmericanplateandthemagmaishig hlyviscous. • TheYellowstonehotspothasbeen initspresentlocationforapproximatelythepast2million years,withthreemajoreruptionsduringthistime. • Eachoftheseeruptionswascataclysmic,result intheformationofagiantcaldera. • Geothermalfeaturessuchasgeysers,mudpots,andfumerolesarevery commonwithinthe park. • Ageyserisasuperheatedfountainofwaterthatsuddenlyspraysintotheaironaperiodicbasis. ThisprocessoccursbecauseboilingwaterbeneathEarthi sconstrictedasitrisesthrougha subterraneanpassageway.Whenthepressurebuildssufficiently,thewaterburstsintothesky. • Amudpotconsistsofabubblingmixtureofa gaseousmudandwater.These systemsform wherehotwaterislimitedandhydrogensulfidegasispresent,creatingsulfuricacid.Thisacid dissolvesthesurroundingrockintofineparticlesofsilicaandclaythatmixwithwhatlittlewater thereistoformthemudpot. • Afumeroleisasteamventthatresultsbecauseunderlyinggroundwaterisboiledawaybefore reachingthesurface. KeyConceptstoRememberAboutVolcanoes 1. Volcanoesoccurmostfrequentlyonplate boundaries.Mostoftheworld ’svolcanoesarefound alongthePacificRingofFire. 2. Volcanoesaremostfrequently associatedwiththeprocessofsubducti onbecauseoceaniccrust meltsandthenrisesthroughcracks inoverlyingcontinentalcrust. 3. Volcaniceruptionscanbebroadlyclassifiedasexplosiveorfluid.Explosiveeruptionsoccurwhen magmaisviscous,formin gcompositevolcanoes.Whenthe magmaisnotviscous,itflowsfreely, resultinginbroadriversoflavathatcollectivelyf ormshieldvolcanoes.Cinder -conevolcanoes evolvethroughtheaccumulationofsolidified magmafragments,rockdebris,andashthatare ejectedfromacentralvent. 4. Somevolcanoesformoverhotspots,whichareplaceswhereupwelling magmareachesthe surface.

Step 2 of 3

Chapter 10.1, Problem 4 is Solved
Step 3 of 3

Textbook: Probability and Statistics for Engineering and the Sciences
Edition: 9
Author: Jay L. Devore
ISBN: 9781305251809

Other solutions

People also purchased

Related chapters

Unlock Textbook Solution

Enter your email below to unlock your verified solution to:

It is common practice in many countries to destroy(shred) refrigerators at the end of