1
, Solutions Manual for Essentials of Geology, 5th Edition by
Stephen Marshak (All Chapters) A+
CHAPTER k1
The kEarth kin kContext
Learning kObjectives
1. Students kshould kbe kaware kof kthe kBig kBang ktheory. kDistant kgalaxies kare kall
kmoving kaway kfrom kus. kThe kfarthest kgalaxies kare kreceding kfrom kus kthe kfastest. kAll
kmatter kin kthe kUniverse kwas kcontained kin ka ksingle kpoint, kapproximately k13.8 kbillion
kyears kago. kAt kthat ktime, kthe kUniverse kexplosively kcame kinto kexistence.
2. Stars, kincluding kour kSun, kare knuclear-fusion kreactors. kFor kmost kof ktheir klife
khistories k(on kthe korder kof kbillions kof kyears), khydrogen katoms kare kfused ktogether kto kform
khelium. kLater kstages kin kstellar kevolution kinclude kfusion kof khelium katoms kand kother,
kheavier kelements; kultimately, kiron kis kthe kheaviest kelement kthat kcan kbe kproduced kthrough
kfusion kreactions kwithin kstars.
3. After ktheir kcycles kof kfusion kare kcomplete, klarge kstars kviolently kexplode
k(forming ksupernovas), kproducing kelements kheavier kthan kiron kand kleaving kbehind ka
kresidue kof kdiffuse knebulae, kwhich kmay kbe krecycled kto kform ka knew kstar kat ksome
kfuture kpoint.
4. Our kSolar kSystem kis kapproximately k4.57 kGa k(billion kyears kold). kAll keight kplanets
krevolve karound kthe kSun kin kcoplanar, kelliptical korbits. kAll kplanets korbit kin kthe ksame
kdirection
(counterclockwise, kas kviewed kfrom kabove kEarth’s kNorth kPole). kThese kfacts kimply
2
,ksimultaneous kplanetary kformation kfrom ka kswirling knebula ksurrounding kthe kSun k(the
ksimilarities kin korbits kwould kthen kbe ka knatural kresult kof kconservation kof kangular
kmomentum). kThe kplanets kaccreted kfrom kthis
3
, nebula kthrough kgravitational kattraction kand khaphazard kcollisions. kPluto, klong kconsidered kthe
―ninth kplanet,‖ khas kseen kits kstatus kdemoted; kastronomers know krecognize keight kmajor kplanets.
5. The kterrestrial kplanets k(Mercury, kVenus, kEarth, kand kMars) kare krelatively ksmall,
kdense, kand krocky kworlds. kThe kgiant kplanets kare kpredominantly kcomposed kof kthe klight
kgases khydrogen kand khelium k(Jupiter kand kSaturn) kor kices k(Uranus kand kNeptune); kthey kare
much klarger kand kmuch kless kdense kthan kthe kterrestrial kplanets.
6. Our kMoon kis kthought kto khave koriginated kfrom kdebris kaccumulated kwhen ka
kprotoplanet kcollided kwith kEarth kapproximately k4.53 kGa.
7. The kEarth kSystem kis ksubdivided kinto kthe katmosphere k(gases kand kaerosols kthat
kenvelop kthe kplanet), khydrosphere k(Earth’s kwater), kgeosphere k(solid kEarth), kand kbiosphere
k(living kthings).
8. Earth kis kchemically kdivided kinto ka kthin, krocky kcrust kdominated kby ksilicate kminerals,
ka kthick kmantle kcomposed kmostly kof kiron- kand kmagnesium-rich ksilicates k(subject klocally kto
kpartial kmelting), kand ka kthick, kmetallic kcore kmade kprimarily kof kiron k(the kouter kportion kof
kwhich kis kliquid). kStudents kshould kknow khow kseismic kwaves ktell kus kthat kthe kouter kcore
kmust kbe kliquid.
9. Physically, kthe kuppermost klayers kof kEarth kare kthe krigid klithosphere k(crust kand
kuppermost kmantle) kand kthe kasthenosphere, kwhich kis kweaker kand kflows kplastically. kThe
k―plates‖ kof kplate ktectonics ktheory kare kdiscrete kslabs kof klithosphere, kwhich kmove kwith
krespect kto kone kanother katop kthe kasthenosphere.
4
, Solutions Manual for Essentials of Geology, 5th Edition by
Stephen Marshak (All Chapters) A+
CHAPTER k1
The kEarth kin kContext
Learning kObjectives
1. Students kshould kbe kaware kof kthe kBig kBang ktheory. kDistant kgalaxies kare kall
kmoving kaway kfrom kus. kThe kfarthest kgalaxies kare kreceding kfrom kus kthe kfastest. kAll
kmatter kin kthe kUniverse kwas kcontained kin ka ksingle kpoint, kapproximately k13.8 kbillion
kyears kago. kAt kthat ktime, kthe kUniverse kexplosively kcame kinto kexistence.
2. Stars, kincluding kour kSun, kare knuclear-fusion kreactors. kFor kmost kof ktheir klife
khistories k(on kthe korder kof kbillions kof kyears), khydrogen katoms kare kfused ktogether kto kform
khelium. kLater kstages kin kstellar kevolution kinclude kfusion kof khelium katoms kand kother,
kheavier kelements; kultimately, kiron kis kthe kheaviest kelement kthat kcan kbe kproduced kthrough
kfusion kreactions kwithin kstars.
3. After ktheir kcycles kof kfusion kare kcomplete, klarge kstars kviolently kexplode
k(forming ksupernovas), kproducing kelements kheavier kthan kiron kand kleaving kbehind ka
kresidue kof kdiffuse knebulae, kwhich kmay kbe krecycled kto kform ka knew kstar kat ksome
kfuture kpoint.
4. Our kSolar kSystem kis kapproximately k4.57 kGa k(billion kyears kold). kAll keight kplanets
krevolve karound kthe kSun kin kcoplanar, kelliptical korbits. kAll kplanets korbit kin kthe ksame
kdirection
(counterclockwise, kas kviewed kfrom kabove kEarth’s kNorth kPole). kThese kfacts kimply
2
,ksimultaneous kplanetary kformation kfrom ka kswirling knebula ksurrounding kthe kSun k(the
ksimilarities kin korbits kwould kthen kbe ka knatural kresult kof kconservation kof kangular
kmomentum). kThe kplanets kaccreted kfrom kthis
3
, nebula kthrough kgravitational kattraction kand khaphazard kcollisions. kPluto, klong kconsidered kthe
―ninth kplanet,‖ khas kseen kits kstatus kdemoted; kastronomers know krecognize keight kmajor kplanets.
5. The kterrestrial kplanets k(Mercury, kVenus, kEarth, kand kMars) kare krelatively ksmall,
kdense, kand krocky kworlds. kThe kgiant kplanets kare kpredominantly kcomposed kof kthe klight
kgases khydrogen kand khelium k(Jupiter kand kSaturn) kor kices k(Uranus kand kNeptune); kthey kare
much klarger kand kmuch kless kdense kthan kthe kterrestrial kplanets.
6. Our kMoon kis kthought kto khave koriginated kfrom kdebris kaccumulated kwhen ka
kprotoplanet kcollided kwith kEarth kapproximately k4.53 kGa.
7. The kEarth kSystem kis ksubdivided kinto kthe katmosphere k(gases kand kaerosols kthat
kenvelop kthe kplanet), khydrosphere k(Earth’s kwater), kgeosphere k(solid kEarth), kand kbiosphere
k(living kthings).
8. Earth kis kchemically kdivided kinto ka kthin, krocky kcrust kdominated kby ksilicate kminerals,
ka kthick kmantle kcomposed kmostly kof kiron- kand kmagnesium-rich ksilicates k(subject klocally kto
kpartial kmelting), kand ka kthick, kmetallic kcore kmade kprimarily kof kiron k(the kouter kportion kof
kwhich kis kliquid). kStudents kshould kknow khow kseismic kwaves ktell kus kthat kthe kouter kcore
kmust kbe kliquid.
9. Physically, kthe kuppermost klayers kof kEarth kare kthe krigid klithosphere k(crust kand
kuppermost kmantle) kand kthe kasthenosphere, kwhich kis kweaker kand kflows kplastically. kThe
k―plates‖ kof kplate ktectonics ktheory kare kdiscrete kslabs kof klithosphere, kwhich kmove kwith
krespect kto kone kanother katop kthe kasthenosphere.
4
