chapter 1 - introduction to geology

8/7/2019 CHAPTER 1 - INTRODUCTION TO GEOLOGY

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CHAPTER ONE:CHAPTER ONE:

INTRODUCTION TOINTRODUCTION TOGEOLOGYGEOLOGY


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WHAT IS GEOLOGYWHAT IS GEOLOGY

GeologyGeology the study of this planet earth, its origin (the study of this planet earth, its origin (asalasal),),

history, composition (history, composition (kndgnkndgn), structure and dynamics of how it), structure and dynamics of how itchanges (changes (sistemsistem mcmanamcmana diadia berubahberubah))

Derived from Greek word (Derived from Greek word (geogeo earthearth

andand logoslogos discourse (discourse (perjlnnperjlnn//perubahanperubahan))

An event formed during geological time which involvesAn event formed during geological time which involvesinterpretation (interpretation (dterjemahkandterjemahkan) and also observation of the event) and also observation of the eventthat occurred and is still occurring at present in our earth :that occurred and is still occurring at present in our earth :

perubahanperubahan ygyg bpnjgnbpnjgn drdr duludulu sampaisampai skrgskrg..

Geological processes takes place during the very large span ofGeological processes takes place during the very large span ofgeologicalgeological timeperubahntimeperubahn ygyg ambilambil masamasa ygyg amatamat pnjgpnjg..

::


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EARTHEARTH

Earth is not a static (Earth is not a static (pegunpegun) body but is in constant) body but is in constantmotion and changes continuallymotion and changes continually

Largest of four planets of inner group solar systemLargest of four planets of inner group solar system(Mercury, Venus, Mars and Moon) and third closest(Mercury, Venus, Mars and Moon) and third closestto the sunto the sun

ShapeShape sphericalspherical

Average radiusAverage radius 6378 km6378 km Surface areaSurface area 510 x 10510 x 1066 kmkm22

Overall densityOverall density 5.5 g/cm5.5 g/cm33

Mount Everest is 8.8 km above sea level : PALINGMount Everest is 8.8 km above sea level : PALINGTINGGITINGGI

Ocean floor is an average 3.7 km below sea levelOcean floor is an average 3.7 km below sea level

Average height above sea level is 7 km : PURATAAverage height above sea level is 7 km : PURATA


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PHYSICAL FEATURES OF THE EARTH Earth is segregated (divided) and concentrated into layers

according to density. The major structural units of the earth based on composition

:

(i) Crust (ii) Mantle (iii) Core

The internal layers of earth based on physical properties are

: (i) Lithosphere (ii) Asthenosphere (iii) Mesosphere (iv)

Core

The two major topographic (geografi) features of earth are :

(i) Continents (dlm dunia ada 7 continent)

(ii) Ocean basins (dasar laut) Material within each of these units is in motion, making earth

a changing dynamic planet : material in major units_ inmantle & in core yg bergerak, yg buat bumi bgrk.

The denser materials are concentrated near the center and

the less dense near the surface : material ketumpatn tinggitertum u d t h2 muka bumi n vice versa.


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INTERNAL STRUCTURE OF EARTHINTERNAL STRUCTURE OF EARTH

CRUSTCRUST LITHOSPHERELITHOSPHERE

MESOSPHEREMESOSPHERE ASTHENOSPHEREASTHENOSPHERE

MANTLEMANTLE

LIQUIDLIQUID

CORECORE OUTEROUTER

SOLID CORESOLID CORE

INNERINNER

CORECORE


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LITHOSPHERELITHOSPHERE

The top of theThe top of the AsthenosphereAsthenosphere is about 100 km belowis about 100 km below

the surface :the surface : tletaktletak 100km100km atasatas asthenosphereasthenosphere.. Above theAbove the AsthenosphereAsthenosphere , the material is solid, strong, the material is solid, strong

and rigid (and rigid (keraskeras xx bgrkbgrk).).

Contains the continental crust of the uppermost part ofContains the continental crust of the uppermost part of

the mantle :the mantle : didi crust,crust, ygyg atasatas sekalisekali..

ASTHENOSPHEREASTHENOSPHERE

Major zone within the upper mantle :Major zone within the upper mantle : zonzon ygyg bsrbsr,, atasatasmantlemantle

Rocks lose much of their strength and become softRocks lose much of their strength and become softplastic and easily deformed :plastic and easily deformed : taktak berapaberapa kuatkuat, soft, soft mcmmcmplastic nplastic n mudahmudah//blhblh berubah2berubah2 bntkbntk..

Thickness is about 200 km.Thickness is about 200 km.


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MESOSPHEREMESOSPHERE

Mesosphere is the region between theMesosphere is the region between the AsthenospherAsthenospherand the coreand the core--mantle boundary.mantle boundary.

The rock below theThe rock below the AsthenosphereAsthenosphere is stronger andis stronger andmore rigid than themore rigid than the AsthenosphereAsthenosphere ::

It is because at this depth the pressure andIt is because at this depth the pressure andtemperature is high.temperature is high.

CORECORE

It is composed mostly of iron.It is composed mostly of iron.

Core has 2 distinct (clearly defined) parts:Core has 2 distinct (clearly defined) parts:

1)1) Solid inner coreSolid inner core2)2) Liquid outer coreLiquid outer core

Heat loss from the core and the rotation of the earthHeat loss from the core and the rotation of the earthprobably causes the liquid outer core generate theprobably causes the liquid outer core generate theEarths magnetic field :Earths magnetic field : habahaba drdr core &core & pusinganpusinganearth,earth, ygyg menjanamenjana medanmedan magnetic.magnetic.


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COMPOSITION LAYERS OF THECOMPOSITION LAYERS OF THE

EARTHEARTH

COMPOSITION LAYERS ARE:COMPOSITION LAYERS ARE:1) CRUST1) CRUST

2) MANTLE2) MANTLE

3) CORE3) CORE


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2) Oceanic Crust : crust d2) Oceanic Crust : crust d bwhbwh dsrdsr lautlaut

Thickness rarely exceed 5 km :Thickness rarely exceed 5 km : jarangjarang sampaisampai 5km.5km.

Denser material :Denser material : ketumpatanketumpatan tinggitinggiBasaltic composition :Basaltic composition : kndgnkndgn basaltic_kndgnbasaltic_kndgn salt.salt.

Average density = 2.9 g/cmAverage density = 2.9 g/cm33

MANTLEMANTLE Constitute 82% of volume and 68% of mass of the Earth.Constitute 82% of volume and 68% of mass of the Earth.

Volume : 82% of earthVolume : 82% of earth

Mass : 68% of earthMass : 68% of earth

Composed of Iron and magnesium silicate rock.Composed of Iron and magnesium silicate rock. Average density = 4.5 g/cmAverage density = 4.5 g/cm33


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CORECORE

OUTER COREOUTER CORE

Thickness is about 2250 kmThickness is about 2250 km

Consist of molten (Consist of molten (caircair//panaspanas) iron and) iron and

nickelnickelAverage density = 10.7 g/cmAverage density = 10.7 g/cm33

INNER COREINNER CORE

Thickness is about 1300 kmThickness is about 1300 kmConsist of iron and nickelConsist of iron and nickel

Average density = 17.0 g/cmAverage density = 17.0 g/cm33


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STRUCTURE OF EARTHSTRUCTURE OF EARTH

2 major principle surface2 major principle surface

(topographic) features of the(topographic) features of the

Earth are:Earth are:

1)1) Continental MassesContinental Masses

2)2) Ocean BasinsOcean Basins


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CONTINENTAL MASSESCONTINENTAL MASSES

Covers about 29% of the Earths surface.Covers about 29% of the Earths surface.

Average elevation (Average elevation (puratapurata tinggitinggi) of about 5 km) of about 5 km

above the floors of the ocean basins and about 1above the floors of the ocean basins and about 1

km above sea level. (5kmkm above sea level. (5km daridari dasardasar kpdkpd arasaraslautlaut nn daridari arasaras lautlaut keke atasatas ikmikm))

Composed largely of rocks known as Granite.Composed largely of rocks known as Granite.

The highest mountain on the continental surfaceThe highest mountain on the continental surfaceis Mount Everestis Mount Everest 29000 feet above sea level.29000 feet above sea level.

Deepest part of the ocean is about 35000 feetDeepest part of the ocean is about 35000 feet

below sea level at Pacific Ocean.below sea level at Pacific Ocean.


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OCEANOCEAN BASINSBASINS

Covers about 70% of the Earths surface.Covers about 70% of the Earths surface.

Irregular :Irregular : taktak sekatasekata// taktak seimbangseimbang..

Posses many deep trenches : valley andPosses many deep trenches : valley andmountain as the continental masses.mountain as the continental masses.

The rock of the ocean are rather dense :The rock of the ocean are rather dense :

tumpattumpat, dark basaltic rock., dark basaltic rock.


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GEOLOGIC PROCESSESGEOLOGIC PROCESSES

Geologic processes that change theGeologic processes that change the

Earths structure are:Earths structure are:

1)1) GradationGradation

2)2) TectonismTectonism

3)3) VolcanismVolcanism


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GRADATIONGRADATION

GradationGradation changes the Earth surfacechanges the Earth surface

1)Degradation1)Degradation

Erosion results from wearing of rocksErosion results from wearing of rocks

by water and air :by water and air : hakisanhakisan batubatu by air nby air n

udaraudara..

2)2)AggradationAggradation

Deposition results in accumulation (btmbh2)Deposition results in accumulation (btmbh2)of sediment and ultimate building up ofof sediment and ultimate building up of

rock strata : sedimentrock strata : sediment mbtkmbtk rock.rock.


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TECTONISMTECTONISM

Plate tectonics is a dynamic process of thePlate tectonics is a dynamic process of the

lithosphericlithospheric plate which move over a weakplate which move over a weak

plastic layer in the upper mantle known asplastic layer in the upper mantle known as

asthenosphereasthenosphere. :. : lithosphericlithospheric plateplate bgrkbgrk atasatasasthenosphereasthenosphere ygyg lemahlemah..

Produce faulting, folding and fracture :Produce faulting, folding and fracture : ygyg

menyebabkanmenyebabkan plateplate tutu berlipatberlipat,, tergelincirtergelincir, n, n

patahpatah..

Responsible for formation of mountain ranges. :Responsible for formation of mountain ranges. :

bertanggungjwbbertanggungjwb dlmdlm perubahanperubahan gununggunung rr bukitbukit..


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VOLCANISMVOLCANISM

Volcano is a vent in the earths crustVolcano is a vent in the earths crust

through which molten rock materials withinthrough which molten rock materials within

the earth, lavas, ashes steam and gas arethe earth, lavas, ashes steam and gas are

ejectedejected

Responsible for the formation of plutonicResponsible for the formation of plutonic

rocksrocks

Volcanoes are located along of tectonicVolcanoes are located along of tectonic

plates. :plates. : terletakterletak sepnjgsepnjg plat tectonic, refplat tectonic, ref

tectonismtectonism..


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THANK YOUTHANK YOU

chapter 1 - introduction to geology

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