The Rock Cycle the Cyclingofmatter Andtheflow Ofenergy

LONumber=6E1_0330; CorrectionKey=NL-A DO NOT EDIT--Changes mustbemadethrough "Fileinfo" 22 Unit 1TheDynamic Earth The Rock Cycle the cyclingofmatter andtheflow ofenergy. form varioustypesofrock andhowthey involve you willbeabletodescribe theprocesses that By theendofthislesson . . sandstone arches. Arches NationalPark inUtah isknownforitsbeautiful LESSON 2 LESSON

© Houghton Mifflin Harcourt • Image Credits: ©robertharding/Alamy 1. Grand Canyonwere formedandshapedoverlongperiodsoftime. The Colorado Riverflowsthrough theGrand Canyon.Thevarietyofrocks thatmake upthe explain howthe Grand Canyonformed andchangedovertime. EVIDENCE NOTEBOOK they donow? picture. Howdidtheserock layersform?Didtheserock layersalwayslooktheway Look closelyattherock layersthatmake upthewallsofGrand Canyonin the How was the rock in this image of the Grand Canyon Canyon Grand inHow image rock of this the the was CAN YOU EXPLAIN IT? IT? YOUCAN EXPLAIN formed and shaped over shaped and time?formed As youexplore thelesson, gatherevidencetohelp download additionallabresources. the Hands-OnLabforthislesson andto Go onlinetoviewthedigitalversionof Lesson 2TheRock Cycle 23 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 24 3. some canonlybeseenwithamicroscope. determines itssize.Somecrystalsare verylarge and in arepeating pattern. The waythecrystalforms is asolidwithitsatomsormoleculesarranged also form. left behindaswatermoleculesevaporate, minerals substances thatare dissolved inliquidwaterare minerals toreorganize, forminganewmineral. When pressure withinEarthcausetheatomsinexisting together toformdifferent minerals. Earth. Lavaismoltenrock on Earth’s surface. Asmagmaorlavacools,theatomsjoin processes. Someminerals formwhenmagmaorlavacools.Magmaismoltenrock inside the mineral formsalsoaffect amineral’s properties. Minerals formbydifferent natural kinds ofatomsormoleculesthatmake upthemineral. Theconditionsunderwhich composition andanorderly internalstructure. Amineral’s properties dependonthe A mineral isanaturally occurring andusuallyinorganic solid.Ithasadefinitechemical Minerals 2. of rocks. well aswhichminerals make updifferent kinds form, youmustunderstandmineral formationas of allrocks are minerals. To understandhowrocks rocks maydiffer inappearance, thekey ingredients makes upthewallsofGrand Canyon.Although are manytypesofrock beyondthelayered rock that Many partsofEarthare madeupofsolidrock. There Unit 1TheDynamic Earth C. B. A. mineral? Selectallthatapply. Which ofthefollowingprocesses canforma made ofthesamematerials?Whyorwhynot? in thephotograph. Doyouthinkthewholerock is Describe thecolorsandappearance oftherock Minerals are madeupofcrystals.Acrystal Minerals canalsoform whentemperature and erosion ofsediments changing heatandpressure cooling ofmeltedrock Comparing Minerals and Rocks EXPLORATION 1 near theedgeofalake inSweden. Different colorsandpatterns canbeseeninthisrock found mineral crystalsintheworld! gypsum crystals.Theseare nowconsidered tobethelargest years, dissolved minerals inthewaterslowlyformedthese This caveinMexicowasoncefull ofwater. Overmillionsof

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© Houghton Mifflin Harcourt • Image Credits: (t) ©Joyce Photographics/Photo Researchers, Inc.; (tc) ©Dirk Wiersma/Science Source; (bc) ©Trevor Clifford Photography/ Science Source; (b) ©robertharding/Alamy 4. Magma caneventuallycoolandsolidifytoformnewrock. Earth’s surface,rock maygethotenoughtomeltandformmagma. changing oftheminerals formsanewtypeofrock. Very deepbelow high enough,theminerals inarock canchangeintonewminerals. The during theformationofmountains.Ifpressure andtemperature are deep belowEarth temperature orpressure. Thischangemayhappenwhenrock isburied hardened, andcementedtoformnewrock. be depositedinlayerslow-lyingareas. Sedimentcanbeburied, into smallerparticlescalledsediment.Overtime,thesedimentcan another typeofrock. For example,weatheringcanbreak downrocks long periodsoftime,natural processes changeonetypeofrock into Where dorocks comefrom? Rockscomefrom otherrocks. Over Rocks way arock formsplayintheappearance ofrocks? What role doyouthinktheminerals thatmake uparock andthe 7. 6. Discuss Withapartner, writesomeobservationsoftherock TypesIdentify Rock of Rocks canalsoformwhenexistingrock experiencesanincrease in temperature /pressure This rock’s formationlikely resulted from changesin and itssurroundings? Howmightthisrock haveformed? formation inthepicture. Whatdoyounoticeabouttherock 5. EVIDENCE NOTEBOOK your notebook. form thelayersofGrand Canyon?Listthesein What characteristics doyouseeintherocks that ’ s surfaceorwhenrock isstretched orsqueezed . intense pressure andtemperature. changed from theiroriginalformby bands ofminerals thatwere chemically This rock ismadeupoflightanddark cemented overtime. that were pressed togetherandthen This rock ismadeupoflayerssand far beneathEarth’s surface. This rock formedwhenmagmacooled Lesson 2TheRock Cycle 25 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 26 9. rock formation. have seenafewmomentsoftheprocess of have everseenvideoofaneruptingvolcano,you most rock maynotbenoticeable.However, if you millions ofyears. processes intherock cyclemaytake hundreds of crust. Thenitmaymelttoformmagma.These exists nowmayeventuallyendupbackbelowEarth’s magma atsomepointinthepast.Likewise, rock that imagine thattheyhappencontinuously. Allrock thatisonandinsideEarthwas The processes onEarththatformrock take suchalongtimethatitishard to Geological Processes 8. Discuss minerals. Otherigneous rocks havefewerminerals intheirmake-up. quickly thatmagmaorlavacooled.Someigneousrocks are madeupofmanytypes depends onthechemicalmake-up ofthemagmaorlavathatformeditandonhow common atthesidesandbaseofvolcanoes. onto Earth’s surface.Extrusiveigneousrock is igneous rock formswhenlavaerupts,orisextruded, the rock belowEarth’s surfaceandcools.Extrusive rock formswhenmagmapushes,orintrudes,into between surrounding rock layers.Intrusiveigneous cools belowground inlarge chambers,incracks, or above ground bothformigneousrocks. Magma Cooling magmabelowground andcoolinglava Rock Igneous Unit 1TheDynamic Earth why youthinkyourconclusioniscorrect. rocks formedfrom magmabeneathEarth’s surface?Together with apartner, discuss rock forming? process eventuallyleadtoigneous beneath Earth’s surface?Howdoesthemelting What happenstothematter in rock whenitmelts The flowofenergy andmatter thatforms The mineral compositionofigneousrocks Relating Igneous System Rocks the to Earth Do youthinkthattherock in thepicture tookmore orless timetocoolthan EXPLORATION 2 Lava flowsoften coolquickly, hardening intorock. through atropical forest inHawaii. Lava from avolcaniceruptionflows Explore ONLINE!

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Hands-On Lab Model Crystal Formation

How do crystals form? You will use salt to observe crystal formation MATERIALS and draw conclusions about the factors that affect crystal size. Salt is found in natural bodies of water all over the world, • three beakers, 250 mL especially in oceans and in some inland lakes. When salt water • Epsom salts evaporates or changes temperature, salt crystals may form. • graduated cylinder, 100 mL • hot plate • small saucepan Procedure • spoon or stirring rod • tongs STEP 1 Add the following to each of the three beakers until each 2 • 3 test tubes, tempered glass is __ full: 3 • hot gloves, terrycloth • beaker 1—water and ice cubes • beaker 2—water at room temperature • beaker 3—hot tap water

STEP 2 Place 120 mL of water in a saucepan. Heat on a hot plate over low heat until warm. Add 90–100g of Epsom salts and stir until dissolved. DO NOT let the mixture boil. Keep adding small amounts of salt until the crystals no longer dissolve in the water.

STEP 3 Using a graduated cylinder, carefully pour equal amounts of the Epsom salts mixture into three test tubes. Be sure not to include any salt from the bottom of the pan to the test tubes. Use tongs to steady the test tubes as you pour. Drop a few crystals of Epsom salt into each test tube. Then gently shake them. Place a test tube into each beaker.

STEP 4 Cool the test tubes for 15 minutes. Observe what happens. Use this table or create your own and record your observations during those 15 minutes. You may write or draw what you observe.

Beaker Observations - 15 minutes

Beaker 1 Beaker 2 Beaker 3 © Houghton Mifflin Harcourt

Analysis STEP 5 In which beaker did the largest crystals form? How did the temperature and the amount of time affect the size of the crystals?

Lesson 2 The Rock Cycle 27 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 28 intrusive igneous rock, especiallygranite. The Rockies,thelargest mountainrange ofwesternNorthAmerica,are intrusive igneousrock maybeexposedatEarth’s surfaceifthelayersaboveare eroded. Earth’s crustare pushedtoward thesurfaceduringaprocess calleduplift. Then,the However, notallintrusiverock remains underground. For example,large regions of it formed.Intrusiveigneousrock islocatedbeneathEarth’s surface,where itformed. Extrusive igneousrock, suchasbasalt,iseasilyfoundonEarth’s surface.Thisiswhere Geosphere in the Rock Igneous 10. These igneousrocks cooledatdifferent rates. form. Obsidianisglassy inappearance andiscalledvolcanic glass. Obsidian (ahb•SID•ee•uhn)isanigneousrock thatcoolssorapidly thatnocrystals results insmallercrystals.Super-fast coolingofmagmacanresult innocrystalsatall. cool atdifferent rates. Remember:slowcoolingresults inlarger crystals.Fast cooling andesite are commonigneousrocks thatformonEarth’s surface. are madeupofverysmallcrystals.Theserocks are saidtobe“fine-grained.” Basaltand quickly whenexposedtoair. Becausethere islittle timeforcrystalstoform,theserocks igneous rocks thatformbelowEarth’s surfaceare granite anddolerite. have large, visiblecrystals.Theserocks are describedas“coarse-grained.” Examplesof the more timecrystalshavetogrow. Rocksformedunder theseconditionsgenerally insulated bysurrounding rock, soitcoolsveryslowly. Thelongerthecoolingtakes, thousands ofyears.Whenigneousrock formsbelowEarth’s surface,themagmaiswell The timescalefortheformationofigneousrocks variesfrom minutestohundreds of Scale Time Unit 1TheDynamic Earth your answer? evidence ofthelongestcoolingprocess? Whatevidencedoyouseetosupport Compare thepictures oftheigneousrocks. Which ofthethree rocks shows Rocks withthesamechemistrycanhaveverydifferent appearances whenthey On theotherhand,magmathatreaches Earth’s surface,calledlava,coolsvery dolerite granite basalt mademostlyof

© Houghton Mifflin Harcourt • Image Credits: (tl) ©Stan Strange/EyeEm/Getty Images; (tr) ©Diane Cook & Len Jenshel/National Geographic/Getty Images; (b) ©Loi Nguyen/Moment/ Getty Images 11. exposed after thesurrounding rock eroded away. columns formedunderground. Thecolumnslaterbecame toward Earth’s surface.Geologistshypothesizethatthe Wyoming, showtheresult ofmagmaforcing itswayup The igneousrock columnsmakingupDevilsTower, Igneous Rock Igneous 12. be weathered anderoded. ice ages,thegranite ofmassive mountainsmay For example,asglaciersgrow andshrinkduring may alsobeafactorintheweatheringofrocks. by wind,water, andorganisms. Climaticchange As with all rocks, igneous rocks can be weathered Observe How Igneous Rock Forms and Changes formations haveincommonasrelated toenergy flowintheEarthsystem? Compare andcontrast thetworock formationsshownabove.Whatdothese formation ofHalfDome.Write numbers Order theeventsthatlikely ledtothe 1–4

A A glaciermovedovertheexposed The granite wasuplifted withthe The surrounding rock wasweathered granite anderoded therock. surrounding rock. and eroded. and formedgranite rock. onthelinestoorder theevents. body ofmagmacooledunderground granite thathasweathered withtime. Park, California,isHalfDome.Itmadeofintrusiveigneous One oftheiconicrock formationsfoundinYosemite National enough toholdaboveyourheadwithlittle effort. example ofthistypeigneousrock andcanbelight gas. Thisleavespockets ofairintherock. Pumiceisan appearance becausethelavacontainedbubblesof Quick-cooling igneousrock often hasaspongy Half Dome Lesson 2TheRock Cycle 29 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 30 of limestoneform thisway. chemicals thatremain crystallize to formminerals. Saltandvariouskinds Sometimes minerals form whenthewaterinwhichtheyare dissolved evaporates. The atoms rearrange. Overmillionsofyears,this process mayformcoal. and exposedtothehighertemperatures andpressures beneathEarth’s surface,its and animals.For example,whenlayeruponofplantmaterialisburied,compacted, sediment piecesandcementthemtogether. on lowerlayersofsediment.Atthesametime,dissolved minerals solidifybetween processes happenwhentheweightofoverlyinglayerssoilandsedimentpress down How doessedimentgetpressed together, orcompacted,andcemented?Often these Geological Processes 13. called mudstoneismadeupmostlyofcementedmudparticles. fragments theycontain.For example,onetypeofsedimentaryrock are commonsedimentary cements. deposited oritmayentertherock later. Theminerals quartzandcalcite cements sedimentintorock maybemixedwiththesedimentwhenitis sedimentary rock ismadeofsediment.Themineral “glue” that may take uptomillionsofyearsoccur minerals, sedimentaryrock When sedimentsare compactedorare cementedtogether bynew Rock Sedimentary Relating Sedimentary System Rocks the to Earth Unit 1TheDynamic Earth over time. rock ispartofthecyclingEarthmaterials up sedimentaryrock? Explain howsedimentary What processes formthesedimentthatmakes Sedimentary rock, however, doesnotalways formfrom layersofsediment. Sedimentary rocks mayalsoformfrom theremains offossils ofonce-livingplants Sedimentary rocks are namedaccording tothesizeandtypeof forms. Thisprocess isgradual and . Like thenamesuggests, EXPLORATION 3 and amountofsedimentdeposited. be different colorsandthicknesses, dependingonthetype Sedimentary rock mayformindistinctlayers.Thelayerscan large, compactedrock fragments. breccia (BREHCH-ee-uh)ismadeupof Some sedimentaryrock, like this

© Houghton Mifflin Harcourt • Image Credits: ©Voy/Alamy below tofindout. completely buriedintravertine? Completethesteps many yearswillittake forthesarcophagus tobe a rate ofdeposition 2mm/yearonaverage, how 3 mbelowthetopofsarcophagus. Assuming The topofthetravertine layer showninthephotois 14. One WayOne Rock Forms Sedimentary deposited overtime. Sediment andorganic materialsare

Howlongwillittake forthesarcophagus tobecompletelyburied? 16. D. Rocklayersformedwhenmagmabeneaththelake cooled. C. B. Theoldestrocks are foundinthetoplayers. A. Select thestatementsthatcorrectly describeapartoftheprocess shownabove. SE 2 STEP SE 1 STEP SE 3 STEP when designingamachinethatcouldcreate thisrock inalab? lab environment. Howwouldyourknowledgeoftheformationsandstonehelp EngineerIt 15. Therocks inthisscene containonce-livingthings. The sedimentisbroken downrock from theedgeoflake. Buried Time in the MathDo

Then, setupaproportion. Usethevariablentorepresent theunknown: First, convertmeterstomillimeters:3m= Solve theproportion. ____ 2 mm 1 yr

= Sandstone isatypeofsedimentaryrock thatcanbeformed ina ______

mm yr settle, theyformlayers. As thesematerialsbreak downand 2,000-year-old sarcophagus while therock formationgrows. deposits thatcausethisrock formationtoslowlybury this In Turkey, calcium-richhot springsleavebehindmineral cemented toformsedimentaryrock. These layersare compactedand mm Lesson 2TheRock Cycle Explore ONLINE! 31 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 32 the canyonwalls. helped toshapetheGrand Canyonandexposethemanycolorfullayersthatmake up formations weseetoday. For example, overmillionsofyearstheColorado Riverhas surface. Then,weatheringand erosion mightexposeandshapetherock intothe a sedimentaryrock formsunderthesurface,uplift canpushtherock uptoward the leave theminerals andsaltsbehind,whichcancementthesedimentstogether. After contains manydissolved minerals andsalts.Water canflowthrough sedimentsand of sedimentandrock, overthousandsormillionsofyears. pressure neededforcompactionofsomesedimentaryrocks happensundermanylayers sedimentary rocks, thatdoesnotmeantheywere formedonornearthesurface.The Sedimentary rock isoften identifiedbyitsvisiblelayers.Eventhoughyoucanseethese Sedimentary Rock in the Geosphere 17. Discuss Look attheimagesandread aboutthe limestone. are buriedandcompactedforalongtimetoform a lake. Thesesedimentsaccumulateslowlyand organisms builduponthefloorofoceanor of limestoneformastheremains oftinyaquatic millions ofyearstoform.For example,sometypes of sedimentsmaytake manythousandsoreven formed from thecompactionandcementation that sedimentaryrock canform.Sedimentaryrock out ofsolutionisactuallyonethefasterways years. Butthedepositionofcalciumcarbonate slowly overaperiodofyears—about2cmin10 could observethetravertine depositgrowing very Sedimentary rock formsslowlyovertime.Aperson Scale Time Unit 1TheDynamic Earth shale andlimestoneformation. a partner, compare andcontrast theprocess of formation ofshaleandlimestone.Together with Water playsakey role informing, aswellexposing,sedimentaryrock. Water clay sediments. burial, andcompactionofveryfineclaysediments. Shale may take millions ofyears to form by sedimentary rocks. the ceilingsofcavesformrapidly whencompared toother calcium carbonate.Limestonestalactiteshangingfrom Limestone mayformbythedepositionofdissolved slow accumulation, slow accumulation,

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© Houghton Mifflin Harcourt • Image Credits: (tl) ©Education Images/Contributor/Universal Images Group/Getty Images; (tc) ©ChinaFotoPress/Contributor/ChinaFotoPress via Getty Images; (tr) ©GUIZIOU Franck/hemis.fr/Getty Images; (b) ©Albert Roseo Photography/Getty Images 18. Examples of Sedimentary Rock Sedimentary of Examples cemented together. of large piecesofsedimentlater Conglomerate rocks are made 20. exposing newlayers. weather anderode sedimentaryrock, sometimes affected byitssurroundings. Windandwatercan Like othertypesofrock, sedimentaryrock canbe Changes and Forms Rock Sedimentary How Identify compaction, ordeposition?Explainyouranswer. Which ofthesethree words appliestoalltypesofsedimentary rock: weathering, Monument Valley asitappearstoday. events thatcouldhaveledtotheformationof Use whatyouknowtowriteaseriesofthree 19. EVIDENCE NOTEBOOK changed overtime? If so,howlongdoyouthinkittooktoformandhastherock Do youseeanyevidenceofsedimentaryrock intheGrand Canyon? composition andgrain size. are duetodifferences inthemineral The different colorsandtextures Province, China,are sandstone. The RainbowMountainsofGansu years havecarriedmuchofthe rock away. rivers thatfloodedoveritatvarious timesovermillionsof Amazingly itshorizontallayersare undisturbed!However, the rock toitscurrent positionof2000mabovesealevel. then nearsealevel.Sincethen, dramatic uplift hasmoved approximately 300to100millionyearsagoatwhatwas The sedimentaryrock ofMonumentValley, Arizona, formed ocean-dwelling organisms. calcium carbonateshellsoftiny They are composedlargely ofthe are madeofchalkylimestone. The WhiteCliffs ofDover, England, Lesson 2TheRock Cycle 33 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 34 pressures, andeachcontainsparticularkindsofminerals. Each typeofmetamorphicrock formsunderacertainrange oftemperatures and to changeandformnewminerals, therock thenbecomes anewmetamorphicrock. When rock isexposedtophysicalorchemicalconditionsthatcausetherock’s minerals Geological Processes 21. Discuss Together withapartner, discuss whythegneiss rock shownabovehasboth a different kindofrock. Over millionsofyears,thesolidrock maychangeto crust. Thetemperature andpressure are veryhigh. reach ranges of200°Cto1200°C. metamorphism whentheirtemperatures typically is anotherword forthischange.Rocksundergo can alsocausechangestorock. Metamorphism metamorphic rock forms.Contactwithhotfluids of existingrock tochangeovermillionsofyears, or bothcausethetexture andmineral content When large changesoftemperature, pressure, Metamorphic Rock Metamorphic Rock May Form aMagma Near Chamber Relating Metamorphic System Rocks the to Earth Unit 1TheDynamic Earth light bandsanddarkbands. Imagine arock thatisburieddeepinEarth’s magma EXPLORATION 4 temperatures deepwithinEarth’s crust. Gneiss (NYS) isametamorphicrock. Itformsathigh very hightemperatures. magma, where theshale isexposedto forms inthezoneofshaleclosest to Hornfels isametamorphicrock that

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© Houghton Mifflin Harcourt • Image Credits: (tl) ©Ryan Chylinski/iStock/Getty Images Plus/Getty Images; (tr) ©Photos by R A Kearton/Moment Open/Getty Images; (cl) ©Maciej Figiel - Texture/Alamy; (cr) ©RF Company/Alamy; (bl) ©geoz/Alamy; (br) ©De Agostini Picture Library/Getty Images 22. grains todisappear. This causesthesandgrains tofuseandgrow larger andthespacesbetweensand when sandstone,asedimentaryrock, isexposedtohightemperature andpressure. areas ofrock canbechangedintodifferent typesofrock. a large region ofrock issubjectedtointenseheatandpressure. Inthissituation,large rock. Rockcanalsoundergo metamorphismwhenitisburieddeepenoughinEarththat chamber. Theintenseheatofthemagmachambercanchangeminerals innearby of formation. of metamorphicrock thatformsdependsontheparent rock andtheconditions of anewtyperock—a metamorphicrock different from theoriginalrock. Thekind the physicalandchemicalmake-up oftherock. Thesechangesresult intheformation metamorphic rock. Increased temperature andpressure cancausechangestoboth All three kindsofrock—sedimentary, igneous,ormetamorphic—canchangeintonew Metamorphic RockFormation basalt shale slate Asedimentaryrock ismostlikely tochangeintometamorphic rock after A. Circle theanswerthatbest completeseachstatement. Metamorphicrocks are B. An exampleofmetamorphicrock transformation isquartzite.Quartziteforms Metamorphic rock canforminareas thatare incontactwithorclosetoamagma changes toother metamorphicrock. heating /erosionheating /deposition Before usually /never /sometimes be seen. enough forindividualminerals to 850 °C.Amphibolitehasgrains coarse to temperatures between500°Cand change intoamphibolitewhenexposed Basalt isanigneousrock thatcan gives phylliteaslightsheen. mica formduringmetamorphism.This Tiny platesofasparklingmineral called to increased temperature andpressure. can becomephyllitewhenitisexposed other typesofmetamorphicrock. Slate Metamorphic rocks canchangeinto flat, sheet-like layers. minerals havebecomesqueezedinto is ametamorphicrock inwhichthe time—perhaps millionsofyears.Slate increases overaverylongperiodof moderate pressure andtemperature Slate results from exposingshaleto Metamorphosis . produced by Lesson 2TheRock Cycle After amphibolite phyllite slate 35 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 36 but relatively lowtemperature. below Earth’s surface.Blueschistsformunderhighpressure one, formunderhighpressure andhightemperature, far Schist isoften categorizedbycolor. Greenschists, like this rocks willhavelarge grains thatare arranged inanunstructured manner. Other kindsofmetamorphicrocks willnotshowthiskind ofstructure. Instead,these pressure ontherock mayforce themineral crystalsintoparallel darkandlightbands. removes layersofrock. years ago.Metamorphicrock maybemovedtothesurface byuplift orafter erosion when theedgesofNorthAmericaandAfricacrashed together hundreds millionsof of making upmuchoftheAppalachianMountainsare metamorphicrock. Thisrock formed If metamorphicrock formsdeep insideEarth,howare youabletoseeit? Theridges Geosphere inMetamorphic the Rocks 24. 23. with larger mineral crystals,suchasgneiss, maytake tensofmillionsyears. happen torock initssolidstate.Theprocess toformcoarser-grained metamorphicrocks The formationofmetamorphicrock isgenerally averyslowprocess becausethechanges Scale Time Unit 1TheDynamic Earth What happenstotheminerals inrocks thatundergo metamorphism? form extrusiveigneousrock? How does the time it takes to form metamorphic rock compare to the time it takes to Some rocks are easytoidentifyasmetamorphic.Whenametamorphicrock forms, greenschist metamorphic rock called gneiss. bands oflightanddarkminerals asittransforms into another eventually causeitsminerals toseparate intoalternating Exposing schisttohighertemperature andpressure can gneiss

© Houghton Mifflin Harcourt • Image Credits: (t) ©F1online digitale Bildagentur GmbH/ Alamy; (b) ©Grant Dixon/Lonely Planet Images/Getty Images 25. Discuss Isitpossible formetamorphicrock to 26. patterns. over time.Theweatheringmayexposemineral and sedimentaryrock, canalsobeweathered by intensepressure. solid crystals.Somerocks maybebentorfolded of minerals causedbythereorganization ofthe Many metamorphicrocks have wavypatterns applied torock affect therock’ kinds ofmetamorphicrock. Unevenpressures can evenchangemetamorphicrock intodifferent strong forces thathelpedformit.Theseforces Metamorphic rock often showsevidenceofthe How Metamorphic FormsDescribe Rock your reasoning. discuss youranswerandexplain form onEarth’s surface?Together withapartner, rock asitappearstoday. that couldhaveledtotheformationofthis metamorphic rock todescribethree events Use whatyouknowabouttheformationof Metamorphic rocks, justlike igneous s appearance. material forgrand monumentsduetoitsbeauty. as hard asgranite. However, marbleischosenasabuilding resulted inharder andlongerlastingmarble.Marbleisnot limestone grew, fillingthespacesinlimestone.This When thismarbleformed,thecalcitecrystalsinoriginal ago. Itwasuplifted andcarvedbyerosion intovastcliffs. This marbleformedbeneaththeoceanfloormillionsofyears to theintenseforces experiencedduringitsmetamorphism. eroded partofitaway. Thewavybandsofminerals are aclue This metamorphicrock wasexposedafter glacialmovement marble Lesson 2TheRock Cycle 37 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 38 shells atthebeachintotinyfragments. The actionofwaveshasbroken up 28. rock cycletoshowhowtheprocesses thatformdifferent kindsofrocks are related. have onedefinedpathway. Thepathwaysare more like aweb.You canusea model ofthe processes related to eachother?Howdotheyrecycle matter onEarth? and metamorphic—andthefactorsthatinfluencethose processes. Howare these Think aboutalltheprocesses thatformthethree kindsofrock—igneous, sedimentary, Cycle Rock The 27. rock cycleisonewaythatmatter isrecycled onEarth. processes, inwhichrocks changefrom onetypetoanother, iscalledtherock cycle.The undergo changes.Thesechangessometimesformnewkinds ofrock. Thisseriesof pressure beneathEarth’s surfaceandweatheringonEarth’s surface.Asaresult, rocks Although rocks seemsolidandunchanging,theycanbeaffected bytemperatures and Unit 1TheDynamic Earth Meltingandcooling: A. Circle theenergy source fortheseprocesses intherock cycle. the future. describe aprocess intherock cycle thatthemarbleinquarrymightundergo in processes couldturntheshellfragments intolimestoneandthenmarble.Then These photoscouldbeconnectedbyprocesses intherock cycle.Describewhat Changing temperature andpressure: C. B. Erosion The processes thatform different kindsofrock andrecycle matter onEarthdonot and deposition: Modeling the Rock Cycle sun /Earth’s interior sun /Earth’s interior ocean floor. This limestonewasextracted from the EXPLORATION 5 sun /Earth’s interior several milesinland. This marblewascutfrom aquarry

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A Model of the Rock Cycle

29. Complete the rock cycle diagram by writing sedimentary rock or igneous rock. Metamorphic rock has been filled in for you.

ion at nt m e el m ti e n c g & & , c n o io o t deposition, l i erosion, i s cementation n o g

n heat &

o &

i pressure

melting & cooling

he metamorphic rock at & pressure ;

eSE: MS_CNLESE814301_321A 5-4-16 30. Discuss Together with a partner, describe how this rock cycle model provides a 3rd pass Leslie Kell visual representation of the cycling of matter through Earth’s systems.

©Joyce Photographics/Science Source Paths in the Rock Cycle (t) With pressure and temperature changes, sedimentary rock may become metamorphic

©Ted Kinsman/Science Source ©Ted rock. Sedimentary rock may melt and cool to form igneous rock. Or sedimentary rock at (l) ; Earth’s surface may break down into sediment that will form new sedimentary rock. Igneous rock can change directly into metamorphic rock while still beneath Earth’s surface, or it might melt and then cool again to form a new igneous rock. Igneous rock at Earth’s surface can be weathered to form sediments that form sedimentary rock. Metamorphic rock can melt and form magma. The magma cools to form igneous rock. Metamorphic rock can also be changed by temperature and pressure to form a ©Dirk Wiersma/Science Source

© Houghton Mifflin Harcourt • Image Credits: © Houghton Mifflin Harcourt • Image Credits: (r) different type of metamorphic rock. Weathering can change metamorphic rock into sediments that will become sedimentary rock.

EVIDENCE NOTEBOOK 31. How did the processes in the rock cycle play a role in the formation of the Grand Canyon? Record your evidence.

Lesson 2 The Rock Cycle 39 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 40 32. 33. result oftheprocesses oftherock cycle.Otherfactorscanalsochangerock. Rocks definealarge partofEarth’s surface.Thoserocks are continuouslychangingasa 34. Draw Inthespaceprovided, draw arock cyclediagram togowithyourstory. Unit 1TheDynamic Earth Write D. Sedimentaryrock willbeeroded before becoming C. Magmawillresult inigneousrock whencooled. B. Igneousrock willchangeasaresult oftemperature A. sediment through atleastfour transformations. discussion oftheenergy source thatisdrivingeachpartoftheprocess. Follow the Tell astoryofteaspoonsedimentmovingthrough therock cycle.Include a Metamorphicrock willbecomeanigneousrock before it becomesanothertypeofmetamorphicrock. another typeofsedimentaryrock. and pressure. always Model the Rock Cycle Sm Language , sometimes Arts , or never tocompletethestatements.

TAKE IT FURTHER

Continue Your Exploration

Name: Date:

Check out the path below or go online to choose one of the other paths shown.

• Hands-On Labs Go online to Coal Mining choose one • Geodes of these other • Propose Your Own Path paths.

Minerals and rocks are used for many purposes, such as building homes, paving roads, and manufacturing consumer items. Before they can be used, rocks and minerals must be mined, or removed from the ground. Some materials are mined from large open pits, called quarries. Others must be removed from deep, underground tunnels. Some common mineral resources are granite, limestone, marble, sand, gravel, gypsum, iron, and copper. Some rocks, such as coal, are burned for heat and to generate electrical energy. Coal is burned in power plants to release chemical energy that is converted to electrical energy. In fact, more than 90% of the coal mined in the United States is used to generate electrical energy. The original source of the energy stored in coal is the sun. Plants absorb sunlight and convert the solar energy into chemical energy that is stored in their stems, roots, and leaves. Hundreds of millions of years ago, remains of plants that died were buried beneath sand, rock, or mud. This created a pocket of carbon-rich materials that were trapped in layers of sediment and rock. Over time, temperature and pressure from these sediments changed the buried plant materials into the coal that we mine today. ©Ann Taylor-Hughes/iStock/Getty Images ©Ann Taylor-Hughes/iStock/Getty

coal seam © Houghton Mifflin Harcourt • Image Credits: © Houghton Mifflin Harcourt • Image Credits: Plus/Getty Images

Coal seams are layers of sedimentary rock that are formed from organic matter over millions of years.

Lesson 2 The Rock Cycle 41 DO NOT EDIT--Changes must be made through “File info” LONumber=6E1_0310; CorrectionKey=NL-A

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Continue Your Exploration

1. Based on how it is formed, what type of rock is coal? A. sedimentary B. igneous C. metamorphic

2. Explain why you think mining for coal almost always requires miners to dig deep into the ground.

3. Draw a model of how the flow of energy relates to the formation, mining, and burning of coal by humans as an energy source. © Houghton Mifflin Harcourt

4. Collaborate Discuss with a classmate how mining for coal may have changed over the years. Research different ways coal is mined. What processes are best used to extract the coal? Provide evidence for your argument.

42 Unit 1 The Dynamic Earth DO NOT EDIT--Changes must be made through “File info” LONumber=6E1_0330; CorrectionKey=NL-B

LESSON 2 SELF CHECK

Can You Explain It?

Name: Date:

How was the rock in this image of the Grand Canyon formed and shaped over time?

EVIDENCE NOTEBOOK Refer to the notes in your Evidence Notebook to help you construct an explanation for how the rock layers formed and were shaped over time.

1. State your claim. Make sure your claim fully explains how the rocks in the Grand Canyon formed and were shaped over time. ©robertharding/Alamy

2. Summarize the evidence you have gathered to support your claim and explain your reasoning. © Houghton Mifflin Harcourt • Image Credits: © Houghton Mifflin Harcourt • Image Credits:

Lesson 2 The Rock Cycle 43 LONumber=6E1_0330; CorrectionKey=NL-B DO NOT EDIT--Changes mustbemadethrough “Fileinfo” 44 Inwhichorder didtheseeventsmostlikely occur 5. 4. 3. Use thephototoanswer Questions3–5. lesson. of your the following to check the understanding questions Answer Whattypeofrock fragments couldbepartofthis 7. Basedonyourobservations,inwhichgeneral 6. 6–7. photo the Questions to answer Use Unit 1TheDynamic Earth the events. Write numbers during thisrock’s formation? D. intrusiveigneous C. B. metamorphic A. sedimentary category wouldyouplacethisrock? Based onyourobservations,inwhichgeneral cementedsediments C. crystalsofdifferent colors B. crystalsofdifferent sizes A. that apply. What doyouobserveinthisrock? Chooseall D. intrusiveigneous C. B. metamorphic A. sedimentary rock? Chooseallthatapply. D. intrusiveigneous C. B. metamorphic A. sedimentary category wouldyouplacethisrock? extrusiveigneous extrusiveigneous extrusiveigneous Crystalsformedintherock. Heatfrom Earth’s interiorformedmagma. Uplift movedtherock tothesurface. Magmabegancooling. 1–4 onthelinestoorder LESSON 2 SELF CHECK 2 LESSON Checkpoints

© Houghton Mifflin Harcourt • Image Credits: (t) ©Harry Taylor/Dorling Kindersley/Science Source; (b) ©Eye Ubiquitous/Alamy DO NOT EDIT--Changes must be made through “File info” LONumber=6E1_0330; CorrectionKey=NL-B

LESSON 2 SELF CHECK

Interactive Review

Complete this section to review the main concepts of the lesson.

Rocks are composed of minerals. A. What characteristics do minerals have in common?

The three rock types are igneous, sedimentary, and metamorphic rock. B. What do all rocks have in common? How is the formation of the three rock types similar? How is their formation different? ©Dirk Wiersma/Science Source ; (b) ©ChinaFotoPress/ (c) ; ©Ted Kinsman/Science Source ©Ted ; (b)

©Gregory MD/Science Source/Getty Igneous, sedimentary, and metamorphic rocks are all part of the rock cycle. ©Carsten Peter/Speleoresearch & ©Carsten Peter/Speleoresearch (t) (bc) ©SuperStock/Alamy ; C. Use the rock cycle diagram to explain how a sedimentary (tc) n ; io at nt m rock could become a metamorphic rock. e el m ti e n c g & & , c n o io o t deposition, l i erosion, i s cementation n o g

n heat &

o &

; (b) i pressure

e © Houghton Mifflin Harcourt • Image Credits: © Houghton Mifflin Harcourt • Image Credits: Geographic.GettyFilms/National Images via Getty Images Contributor/ChinaFotoPress Images melting & cooling

he at & pressure

eSE: MS_CNLESE814301_321A 5-4-16 3rd pass Leslie Kell

Lesson 2 The Rock Cycle 45