Geology for Civil Engineers Semestral Notes PDF

MODULE 1: GEOLOGY ENGAGE What is the importance of learning Geology in the CE profession? Differentiate the theory of continental drift and plate tectonics. How do you think land formations are created? Why is weathering an important factor to consider in the CE...

MODULE 1: GEOLOGY ENGAGE What is the importance of learning Geology in the CE profession? Differentiate the theory of continental drift and plate tectonics. How do you think land formations are created? Why is weathering an important factor to consider in the CE profession? Where is water stored? What is the importance of learning basic concepts of earthquake in CE profession? EXPLORE GEOLOGY Science that deals with Earth’s physical structure and substance, history and the processes that act on it BRANCHES OF GEOLOGY 1. PHYSICALGEOLOGY ▪ Branchofgeologythatdealswiththepresentphysicalpropertiesofearth a) PETROLOGY ▪ Dealswiththemodeofformation,structure,texture,composition,occurrence,and types of ROCKS ▪ MostimportantgeologyinCivilEngineeringpointofview b) MINERALOGY ϕμ_αρδνασαχ / σκνλαζο 14 | Page  ▪ Dealswiththeformation,composition,occurrence,types,propertiesandusesof MINERALS c) STRUCTURALGEOLOGY ▪ AlsoknownasGEOTECTONICorTECTONICgeology ▪ Thestudyofthethree-dimensionaldistributionofrockunitswithrespecttotheir deformation history ▪ Dealswiththeinternalstructureofrockswhichmayresulttotheoccurrenceof faults, joints and folds d) GEOMORPHOLOGY ▪ ThestudyofthephysicalfeaturesoftheEarth’ssurfaceanditsrelationtoits geological structure ▪ Dealswiththedevelopment/transformationofitslandforms e) GEOPHYSICS ▪ Thestudyofthephysicalpropertiesofearth(e.g.Density,magnetism,texture,etc) f) GEOCHEMISTRY ▪ Dealswiththeoccurrence,distribution,mobilityandabundanceofelementsinthe earth’s crust 2. HISTORICAL GEOLOGY ▪ branchofgeologythatfocusesonthepreservedevidenceofgeologicalevents a) STRATIGRAPHY ▪ Concernedwiththeorderandrelativepositionofstrataandtheirrelationshipto geological time scale ▪ Usedforstudyofarchaeologicalremains b) PALEONTOLOGY ▪ Dealswiththestudyoflifeofgeologicpast. ▪ involves the analysis of plant and animal fossils preserved in rocks c) OCEANOGRAPHY ▪ Dealswiththestudyofallaspectsoftheocean ▪ Includesmarinelifeandecosystem ** ALLIED BRANCHES ▪ appliesknowledgeofgeologyinothersciencesand/orfield 1. ENGINEERINGGEOLOGY/GEOLOGYENGINEERING ▪ applicationofgeologyinCivilEngineering 2. MINING GEOLOGY ▪ applicationofgeologyinMiningEngineering 3. GEOHYDROLOGY / HYDROGEOLOGY ▪ dealswithgroundwatermovement EARTH STRUCTURE STRUCTURE OF THE EARTH 15 | Page ϕμ_αρδνασαχ / σκνλαζο ▪ The structure of the Earth consists of various spherical shells or layers that can be categorized in two manners: a)Chemical/Elementalcompositions b)Mechanical/physicalproperties Figure 1. Layers of the Earth COMPOSITIONAL (CHEMICAL) LAYERS OF EARTH ▪ morecommonlydiscussedlayersofearth;layersaredefinedbasedonitschemicalor elemental composition Figure 2. Compositional Layers of Earth 1. CRUST ▪ Consistofseveralelements ▪ 3to5milesthickundertheoceanandapproximately25milesthickunderthe continents ϕμ_αρδνασαχ / σκνλαζο 16 | Page  Figure 2. Composition of Earth Crust 2 TYPES of CRUST a. OCEANICCRUST(Basaltic)71% ▪ Composedofmagmathateruptsontheseafloortocreatebasaltlavaflow;or cools deeper down to create igneous rock gabbro ▪ Sedimentscoattheseafloor,thickestneartheshore ▪ b. CONTINENTALCRUST(Granitic)29% ▪ Madeupofdifferenttypesofrocks ▪ Averagecompositionisgranitewhichislessdensethanmaficigneousrocks oceanic crust ▪ Thickerpartofthecrust 2. MANTLE ▪ Layerunderthecrust,compromises82%ofEarthvolume ▪ About1,800milesdeep ▪ Consistmostlyofsilicaterocksrichinmagnesiumandiron ▪ Heatcausesrockstorise **CONDUCTION – heat transfer through rapid collision of atoms which only happens in solid – heat flows from warmer to cooler places until it reaches same temperature **CONVECTION – process of material that can move and flow and develops convection currents 3. CORE ▪ CenteroftheEarthmadeof85%ironmetaland15%nickel a. Innercore ▪ Solidpartofthecoremadeofiron ▪ Hasaradiusofabout760milesaccordingtoNASA ▪ Hottestlayerofearthat7000°C ϕμ_αρδνασαχ / σκνλαζο 17 | Page  b. Outercore ▪ Liquidpartofthecorecomposedofnickel-ironalloy ▪ About1,355milesthick ▪ Temperatureat5000°C MECHANICAL (PHYSICAL) LAYERS OF EARTH ▪ layersofearthdefinedanddividedbasedonthebehaviorsofthelayers;corresponds to the mechanical properties of the layers a) LITHOSPHERE ▪ thesolid,outerpartoftheEarth;includesthebrittleupperportionofthemantleand the crust, the outermost layers of Earth's structure ▪ boundedbytheatmosphereaboveandtheasthenosphere ▪ sometimescalledtheGeosphereitself b) ASTHENOSPHERE ▪ thesoftupperlayeroftheearth'smantle,belowthelithosphere, ▪ relativelylowresistancetoplasticflowandconvectionisthoughttooccur. c) MESOSPHERE: ▪ layerbelowtheasthenospherebutabovetheoutercore;essentiallythelower mantle. ▪ Despitehightemperatures,theintensepressureinthisregionrestrictsthemovements of the molecules of the silicate material despite being under high temperature, thus making it extremely rigid. d) OUTER CORE ▪ extendsfromthebottomofthemesosphereorthelowermantleandsurroundsthe inner core ▪ extremetemperatureallowsmetalstoremainintheirliquidphases ▪ theonlylayeroftheEarththatisatrueliquid ▪ Strongmagneticfieldiscausedbyconvection e) INNERCORE ▪ solidityisduetotheintensepressurefromtheupperlayers ▪ Spinsatdifferentspeedthantherestoftheplanet,whichisthoughttocausethe Earth’s magnetic field ϕμ_αρδνασαχ / σκνλαζο 18 | Page  Figure 3. Mechanical Layers of Earth CONTINENTAL DRIFT AND PLATE TECTONICS CONTINENTAL DRIFT ▪ developedintheearlypartofthe20thcentury,mostlybyAlfredWegener ▪ allofEarth’scontinentswereoncepartofan enormous,singlelandmass called Pangaea, existed about 240 million years ago and began breaking up about 200 million years ago Other supercontinents: Pannotia formed about 600 million years ago Rodinia existed more than a billion years ago. ϕμ_αρδνασαχ / σκνλαζο 19 | Page PLATE TECTONICS Scientifictheoryofthelarge-scalemotionofseven(7)largeplatesandmovementsof larger number of smaller plates Beganbetween3.3to3.5Byearsago Averagetectonicplatethicknessinthelithosphereisabout100km 7 MajorTectonicPlates ❑ South American Plate (43, 600, 000 sq km) ❑ Indo-Australian Plate (58, 900,000 sq km) ❑ Antarctic Plate (60, 900, 000 sq km) ❑ African Plate (61, 300, 000sq km) ❑ Eurasian Plate (67, 800, 000 sq km) ❑ North American Plate (75, 900, 000 sq km) ❑ Pacific Plate (103, 300, 000 sq km) TYPES OF TECTONIC PLATES 1. OCEANICPLATES Madeofoceaniccrust;composedmostlyofmagnesiumandsiliconminerals 2. CONTINENTALPLATES Madeofcontinentalcrust;composedmainlyofaluminumandsiliconmaterials BOUNDARIES OF TECTONIC PLATES 1. TRANSFORMBOUNDARY ▪ Occurbetweenplateswhichmovepasteachotherbysliding ▪ Platesgetsminimaldamage ▪ LocationsoftheseboundariesarecalledFAULTS 2. DIVERGENTBOUNDARY ▪ Platesslideapartfromeachother ▪ Movesinoppositedirections ▪ Oftenoccursinseafloors,resultingtoanewone ▪ volcanicactivityproducesamidoceanridgeand small earthquakes. 3. CONVERGENTBOUNDARY ▪ Platesmoveagainsteachother ▪ Oneplategoesunderneathanotherplate ▪ Volcanoesandmountainsareformedattheseboundaries MOVEMENT OF PLATES ϕμ_αρδνασαχ / σκνλαζο 20 | Page Mantle convection drives plate tectonic 1. Hot mantle rises at the ridge axis, creating new ocean crust. 2. The top of convection cell moves horizontally away from the ridge crest ,as does the new seafloor 3. The outer limbs of the convection cells plunge down into the deeper mantle, dragging oceanic crust, at the deep-sea trenches 4. Thematerialsinkstothecoreand move horizontally. 5. ThematerialheatsupandreachesthezonewhereItriseagain. LANDFORMS AND EARTH PROCESSES EARTH PROCESS - dynamic actions that occur inside the earth or on the earth’s surface Constructive process: any process that builds earth material or landforms e.g. erosion, transportation of sediments Destructive process: any process that breaks down earth material or destroy landforms e.g. weathering, earthquakes, volcanic eruption WEATHERING - breakdownofrocksatearth’ssurfaceundertheinfluenceofcertainphysicaland chemical agencies FACTORS affecting Weathering: 1.natureofRocks 2.lengthoftime 3.climate PROCESSES OF WEATHERING 1. DISINTEGRATION ▪ theprocessofbreakingupofrocksintosmallpiecesbythemechanicalagenciesof physical agents 2. DECOMPOSITION ▪ theprocessofbreakingupofmineralconstituentstoformnewcomponentsbythe chemical actions of the physical agents 3. DENUDATION ▪ termusedwhentheearthsurfaceiswornawaybythechemicalandmechanical actions of physical agents and the lower layers are exposed TYPES OF WEATHERING 1. PHYSICALWEATHERING - Physical breakdown of rock masses under the attack of certain atmospheric agents ϕμ_αρδνασαχ / σκνλαζο 21 | Page  - A single rock block is broken gradually into smaller irregular fragments and then into particles smaller dimensions - most active in cold, dry, and higher areas of the earth surface - Temperature variations are responsible to a great extent of physical weathering Exfoliation - Curvedplatesofrockarestrippedalsoknownasonion-skinweathering - Oftenresultsindome-shapedhillsordomerocks - Occursalongplanesofpartingcalledjoints - causedbyunequalexpansionandcontraction,sincesomerocksareeither colder or warmer on the outer surface ** FREEZE-THAW WEATHERING - Waterenterscracksonrocksandfreezeswhentemperaturedropsandmeltsand seeps deeper in the crack. Process repeats until rock splits completely 2. CHEMICALWEATHERING - The chemical decomposition of the rock - internal structure of mineral is altered by addition or removal of elements due to the chemical reaction between the atmosphere and the rocks - takes place in the presence of water which dissolves many active gases from the atmosphere - conditions are defined primarily by chemical composition of the rocks humidity and the environmental surrounding the rock under attack Spheroidal Weathering - aformofchemicalweathering,causedbypenetrationofwateratbounding joints/ fractures, attacking from all sides - concentricorsphericalshellsofdecayedrockaresuccessivelyloosenedand separated from a block of rock 3. THERMALSTRESSWEATHERING - sometimes known as isolation weathering - Contributes to both physical and chemical weathering - Temperature change is important in arid and semi-arid regions ▪ Rockssplitapartintofragmentswhenexpandingandcontractingdueto changes in temperature (physical) ▪ Moisturealterscompositionofrockminerals(chemical) 2 MAIN TYPES ▪ thermalfatigue ▪ caused by a rapid change of temperature of a certain point ▪ happen when a surface is repeatedly heated and cooled ▪ thermalshock ϕμ_αρδνασαχ / σκνλαζο 22 | Page  ▪ failure occurs immediately during a single, rapidly applied thermal load 4. BIOLOGICALWEATHERING - Plants and animals can influence rocks - Roots burrow into the rock, weakening the structure of the rock until it breaks away EARTH PROCESS BY WIND: 1. EROSION a. DEFLATION ▪ Processofwindremovingloosematerialfromflatdryareas,uncemented sediments ▪ Occursindeserts,drylakebeds,floodplains,andglacialwashoutplains b. ABRASION ▪ Scrapingofrocksurfacebyfrictionbetweenrocksandmovingparticles 2. TRANSPORTATION ▪ Thetotalsedimentloadcarriedbyawindcanbedividedintotwo a. Bed load ▪ largerandheavierparticlessuchassandsorgravels ▪ movedbythewindsbutnotliftedmorethan30to60cmoftheearthsurface b. Suspended load ▪ finerclayordustparticleswhichareliftedbythemovingwindsbyadistanceof hundreds of meters above the earths surface 3. DEPOSITIONOFSEDIMENT - sedimentsgetdroppedanddepositedformingwhatareknownasAeoliandeposits a. Sanddunes - hugeheapsofsandformedbythenaturaldepositionofwindblownsand - sometimesofcharacteristicsandrecognizableshape - oftenfoundtomigratefromoneplacetoanotherduetochangeinthe direction and velocity of wind 3 Types of Sand Dunes: Barchans or Crescent-Shape dunes ▪ mostcommonoccurrenceandtriangularinsection ▪ steepside: ▪ facingawayfromthedirectionofwind ▪ inclinedatanangleofabout30°to33° ▪ Gentleside ϕμ_αρδνασαχ / σκνλαζο 23 | Page  ▪ liesonthewindwardside ▪ makesanangleabout10°to15° ▪ maximumheight:335meters;horntohornwidth:350meters Transverse Dunes ▪ similartoabarchaninsection ▪ notcurvedinplanlikebarchans ▪ itslongeraxisisbroadlytransversetothedirectionoftheprevailingwinds Longitudinal Dunes ▪ elongatedridgesofsandwiththeirlongeraxisbroadlyparalleltothedirectionof the prevailing wind ▪ 3mheightand200mlonginaverage b. Loess ▪ alooselycompactedyellowish-graydepositofwindblownsedimentofwhich extensive deposits occur BY WATER (COASTAL PROCESSES): 1. EROSION - wearingawayofrockalongthecoastline - CausedbyDestructivewavesonthecoastline - occurswherewaveshavedirectcontactwiththerock a. Hydraulicaction -thisisthesheerpowerofthewavesastheysmashagainstthecliff.Air becomes trapped and compressed into cracks in the rock with explosive force causing the rock to break apart. b. Abrasion -thisiswhenpebblesgrindalongarockplatformorcliffbasemuchlike sandpaper. Over time the rock becomes smooth. c. Attrition - this is when rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded. d. Solution -thisiswhenseawaterdissolvescertaintypesofrocks.IntheUK,chalkand limestone cliffs (soft rock) are prone to this type of erosion. 2. TRANSPORTATION a. Solution-whenmineralsinrockslikechalkandlimestonearedissolvedinseawaterand then carried in solution. The load is not visible. b. Suspension-smallparticlessuchassiltsandclaysaresuspendedintheflowofthe water. c. Saltation-wheresmallpiecesofshingleorlargesandgrainsarebouncedalongthe seabed. d. Traction-wherepebblesandlargermaterialarerolledalongtheseabed. ϕμ_αρδνασαχ / σκνλαζο 24 | Page 3. MASSMOVEMENT a. Rockfall–bitsofrockfalloffthecliffface,usuallyduetofreeze-thawweathering b. Mudflow–saturatedsoilflowsdownaslope c. Landslide–largeblocksofrockslidedownhill d. Rotationalslip–saturatedsoilslumpsdownacurvedsurface 4. DEPOSITION - Whenthesealosesenergy,itdropsthematerialithasbeencarrying - occuroncoastlinesthathave constructivewaves Factors leading to deposition include: wavesstartingtoslowdownandlose shelteredareas,egbays energy littleornowind shallow water GROUND WATER HYDROLOGY the science of the occurrence, distribution, and movement of water below the surface of the earth GROUND WATER ▪ Alsocalledsubsurfacewater ▪ WaterthatoccursbelowthesurfaceofEarth ▪ Occupiesallorpartofthevoidspacesinsoilsorgeologicstrata ▪ animportantsourceofwatersupplythroughouttheworld ▪ 0.58%ofthetotalwaterresourcesavailableinnature,22.21%freshwaterpartand 2.6% of reservoirs ▪ Locatedat4kmdepthinearth’ssurface ▪ usedinirrigation,industries,urbanandruralhomecontinuestoincrease ▪ Regulatedby ▪ quantumandspeedofrains ▪ drynessofair ▪ extentofvaporizationduringrain ▪ porosityandpermeabilityofrocks ▪ Temperature ▪ vegetativecover ▪ slopeofland ▪ waterabsorbingcapacityofsoil ORIGIN OF GROUND WATER 1. Meteoricwater: ▪ Mainsourceofgroundwater ▪ Receivedintheformofrainandsnowthroughinfiltrationofpores,fissuresandjoints 2. ConnateWater: ▪ Existsinporesandcavitiesofsedimentaryrocksofseasandlakes ▪ Alsocalledsedimentarywater 3. MagmaticWater: ▪ Convertswateraftercondensationofvaporasresultofvolcanicactionattimeof entering hot rocks 25 | Page ϕμ_αρδνασαχ / σκνλαζο GROUNDWATER OCCURRENCE ▪ Groundwateroccurrenceiscontrolledbygeology ▪ Groundwateroccurswhenwaterrechargesthesubsurfacethroughcracksandporesin soil and rock 1. ZoneofAeration(unsaturated) ▪ Consistsofintersticesoccupiedpartiallybywaterandpartiallybyair ▪ SoilWaterzone ▪ Sub-soilzone ▪ Capillaryzone 2. ZoneofSaturation(saturated) ▪ Allintersticesarefilledwithwaterunderhydrostaticpressure ▪ Extendsfromtheuppersurfaceofsaturationdowntotheunderlying impermeable rock ▪ Watertable(Phreaticsurface)occursifthereisnooverlyingimpermeablestrata ▪ Formstheuppersurfaceofthezoneofsaturation 4 Types of Geological Formations 1. Aquifers ▪ Asaturatedformationofearthmaterial ▪ Storeswaterandyieldsufficientquantity ▪ Transmitswaterrelativelyeasilyduetohighpermeability ▪ Sandandgravelformgoodaquifers TYPES OF AQUIFERS a. Unconfined Aquifer ▪ Alsocalledwatertable ▪ Upperwatersurfaceisatatmosphericpressure ▪ Abletoriseandfall ▪ Usuallyclosertoearth'ssurface b. ConfinedAquifer ▪ Alsoknownasartesianorpressureaquifers ▪ Belowthelandsurfacesaturatedwithwater ▪ Boundbyimpermeablelayersaboveandbelow ▪ Underpressure ▪ Ifpenetratedbyawell,waterrisesabovethetopofaquifer c. LeakyAquifers ▪ Alsocalledsemi-confinedaquifers ▪ bothofUpperandlowerboundariesareaquitards ▪ Oroneboundaryisanaquitardandtheotherisanaquiclude ϕμ_αρδνασαχ / σκνλαζο 26 | Page 2. Aquitard ▪ Formationthroughwhichseepageispossible ▪ Yieldsignificantcomparedtoanaquifer ▪ Partlypermeable ▪ Appreciablequantitiesofwatermayleaktoanaquiferbelowit 3. Aquiclude ▪ Aporousbutnotpermeablegeologicalformation ▪ Maybearwaterbutdonotyield ▪ Argillaceousrocks,clayandshalearetypicalexamples 4. Aquifuge ▪ Neitheraporousnorpermeablegeologicalformation ▪ Nointerconnectedopenings ▪ Cannottransmitorabsorbwater ▪ Suitableforgroundwateroccurrence ▪ Massivegranitesandquartzitearetypicalexamples EARTHQUAKE ▪ anysuddenshakingofthegroundcausedbythepassageofseismicwavesthrough Earth’s rocks; occur most often along geologic faults ▪ thereleaseofsuddenandextremeenergythatiscausedbyshiftingintheEarth'scrust SEISMOLOGY - thestudyofearthquakesandseismicwavesthatmovethroughandaroundtheearth FAULTS - narrowzoneswhererockmassesmoveinrelationtooneanother - aplanarorgentlycurvedfractureintherocksoftheEarth’scrust,wherecompression or tensional forces cause relative displacement of the rocks on the opposite sides of the fracture - maybevertical,horizontal,orinclinedatanyangle CLASSIFICATION: 1. NormalSlip - the crust is being pulled apart, the overlying (hanging-wall) block moves down with respect to the lower (foot wall) block 2. ReverseSlip ϕμ_αρδνασαχ / σκνλαζο 27 | Page  - the crust is being compressed, the hanging-wall block moves up and over the footwall block – slip on a gently inclined plane is referred to as thrust faulting 3. StrikeSlip - Crustal blocks move sideways past each other, usually along nearly-vertical faults i. SinistralStrikeSlip - far side moves to the left ii. DextralStrikeSlip - far side moves to the right b. ObliqueSlip - involves various combinations of these basic movements FOCUS - exactspotunderneaththeearthsurfaceatwhichanearthquakeoriginates EPICENTER - thepartoftheearth'ssurfacedirectlyabovethefocusofanearthquake INTENSITY ▪ severityofearthquakeshaking ▪ basedonactualeffectsproducedbythequakesontheearth MAGNITUDE ▪ quantitativemeasureofthesizeoftheearthquakeatitssource ▪ basedonthetotalenergyreleased MODIFIED MERCALLI INTENSITY SCALE ▪ measurestheintensityofanearthquakebyobservingitseffectonpeople,the environment and the earth’s surface ▪ labelsanearthquakefromItoXIIdependingontheeffectsoftheearthquake RICHTER MAGNITUDE SCALE ▪ measurestheenergyreleasedbyanearthquakeusingaseismograph ▪ assignsearthquakesanumberbetween1and10inorderofincreasingintensity CAUSES OF EARTHQUAKE 1. DUETOSUPERFICIALMOVEMENTS: - feebleearthquakesarecausedduetosuperficialmovements - dashingwavescausevibrationsalongtheseashore - Water descending along high waterfalls, impinges the valley floor and causes vibrations along the neighboring areas - Athighaltitudesthesnowfallingisanavalanche 2. DUE TO VOLCANIC ERUPTIONS: - Volcaniceruptionscausefeebletremorsinthesurfaceoftheearth - causeaseverevibrationontheadjoiningareaandhavereallydisastrouseffects 3. DUE TO FOLDING OR FAULTING: - causedduetofoldingofthelayersoftheearth’scrust - aremoredisastrousandareknownastectonicearthquakes ϕμ_αρδνασαχ / σκνλαζο 28 | Page  - directlyorindirectlychangethestructuralfeaturesoftheearthcrust CLASSIFICATIONS OF EARTHQUAKE a) BASEDONDEPTHOFFOCUS: ▪ SHALLOW ▪ Lies anywhere up to 50 km below surface ▪ INTERMEDIATE ▪ Originates 50km to 300 km below the surface ▪ DEEP SEATED b) BASEDONCAUSEOFORIGIN ▪ TECTONIC EARTHQUAKES ▪ Due to relative movements of crystal block on faulting ▪ NON-TECTONIC EARTHQUAKES ▪ Due to volcanic eruptions or landslides c) BASEDONINTENSITY ▪ Initially given by Rossi and Ferel (Scale 1-10) ▪ Based on the sensation of people and damage caused Later modified by Mercalli and later by Wood and Neumann EXPLAIN Importance of Geology in Civil Engineering ✔provides a systematic knowledge of construction material, its occurrence, composition, durability, and other properties ✔ knowledge of the geological work of natural agencies helps in planning and carrying out major civil engineering works ✔ knowledge about ground water quantity and depth of occurrence is required in connection with water supply, irrigation, excavation and many other civil engineering works ✔ foundation problems of dams, bridges and buildings are directly concerned with the geology of the area where they are to be built ✔ Helpsgreatlyininterpretingdrillingdataforfoundationworks ✔ the knowledge about the nature and structure of rocks is very necessary in tunneling, road construction, canals, docks and in determining stability of cuts and slopes ✔ naturalformationofsoilmaterialsisnecessaryinsoilmechanics ✔ a detailed geological report which is accompanied by geological maps and sections, is prepared prior major engineering projects ✔ stability of civil engineering structure is considerably increased if the geological feature like faults, joints, bedding planes, folding solution channels etc. in the rock beds are properly located and suitably treated ✔ Planninganddesign,andcostandsafetydependsonsoilconditions PLATE TECTONICS ϕμ_αρδνασαχ / σκνλαζο 29 | Page  FORMATIONS DUE TO MOVEMENTS OF PLATE TECTONICS ❖ PACIFIC RING OF FIRE Most ocean trenches circle the Pacific in the "Ring of Fire," which also includes active volcanoes and earthquake zones. (National Geographic) ❖ MARIANATRENCH:resultofconvergent boundary between the Pacific and Mariana Plates (Pacific moves underneath Mariana) ❖ PUERTO RICO TRENCH, the deepest spot in the Atlantic Ocean, is created where the oceanic crust of the North American plate (carrying the western Atlantic Ocean) is being subducted beneath the ϕμ_αρδνασαχ / σκνλαζο 30 | Page  oceanic crust of the smaller Caribbean plate ❖ HIMALAYAMOUNTAINRANGE:resultof convergent boundary between the Eurasian and Indian Plates ❖ The ALPS in New Zealand are fold mountains created as the tiny Adriatic microplate rotates clockwise against the Eurasian plate to the north. ❖ the Nazca plate is subducting beneath the South American plate, resulting in the ANDES MOUNTAINS ❖ JUAN DE FUCA RIDGE: a mid-ocean spreading center and divergent plate boundary that separates the Pacific Plate to the west and the Juan de Fuca Plate to the east. ϕμ_αρδνασαχ / σκνλαζο 31 | Page  ❖ Iceland:wheretheMID-ATLANTICRIDGEseparatestheNorthAmericanand Eurasian plate ❖ The EAST PACIFIC RISE is a mid-oceanic ridge, a divergent tectonic plate boundary located along the floor of the Pacific Ocean. It separates the Pacific Plate to the west from (north to south) the North American Plate, the Rivera Plate, the Cocos Plate, the Nazca Plate, and the Antarctic Plate. ❖ theArabian,Indian,andAfricanplatesare drifting apart, forming the GREAT RIFT VALLEY in Africa. The Dead Sea fills the rift with seawater ❖ the ALEUTIAN ISLANDS along the pacific is an island arc formed by overriding of the North American plate on the Pacific plate. ❖ The Ryukyu Islands, also known as the Nansei Islands or the Ryukyu Arc. An island arc formed by the Uruma fluctuation – earth’s crust movement that ϕμ_αρδνασαχ / σκνλαζο 32 | Page  occurs along with the formation of the Ryukyu Islands. Since its formation, the islands have repeated uplifting and sinking. LANDFORMS AND EARTH PROCESSES EROSION ϕμ_αρδνασαχ / σκνλαζο 33 | Page ϕμ_αρδνασαχ / σκνλαζο 34 | Page TRANSPORTATION ϕμ_αρδνασαχ / σκνλαζο 35 | Page COASTAL PROCESSES: MASS MOVEMENT RIVER PROCESSES DEPOSITION SAND DUNES ϕμ_αρδνασαχ / σκνλαζο 36 | Page LOESS ϕμ_αρδνασαχ / σκνλαζο 37 | Page CHEMICAL WEATHERING ϕμ_αρδνασαχ / σκνλαζο 38 | Page PHYSICAL WEATHERING ϕμ_αρδνασαχ / σκνλαζο 39 | Page EXFOLIATION WEATHERING ϕμ_αρδνασαχ / σκνλαζο 40 | Page ϕμ_αρδνασαχ / σκνλαζο 41 | Page SPHEROIDAL WEATHERING ϕμ_αρδνασαχ / σκνλαζο 42 | Page ϕμ_αρδνασαχ / σκνλαζο 43 | Page ENGINEERING IMPORTANCE OF WEATHERING ❖ selectionofsuitablequarryfortheextractionofstonesforstructuralanddecorative purposes ❖ weatheringalwayscausesalossinthestrengthoftherocksorsoil ❖ Foraconstructionengineeritisalwaysnecessarytosee: ❖ theextenttheareaunderconsiderationforaproposedprojecthasbeen affected by weathering ❖ thepossibleeffectsofweatheringprocessestypicaloftheareaonthe construction materials ENGINEERING CONSIDERATION FOR EARTH PROCESSES: ϕμ_αρδνασαχ / σκνλαζο 44 | Page  ❖ In general, no site is selected for any type of important work on the moving dunes because such dunes are always a source of trouble ❖ moving dunes damage certain important works ❖ IF compelled to select such a site, special methods should be adopted to check the motion of the moving dunes TYPES OF GEOLOGICAL FORMATIONS AND AQUIFERS EARTHQUAKE FAULTS ✔ Sierra Nevada Fault in California, United Statescasued 1872 Lone Pine Earthquake of M 7.4 – 8.3 Sparta Fault in Greece caused M7.2 Sparta Earthquake in 464BC ✔ Independence Valley Fault system in Nevada United States caused 2008 Wells earthquake – M6.0 ✔ ϕμ_αρδνασαχ / σκνλαζο 45 | Page  ✔ Glarust Thrust in Switzerland exist during Cenozoic Period. ✔ Kern Canyon Fault in Sierra Nevada, California is a thrust fault ✔ Seattle Fault in Washington is an active thrust Fault ✔ San Andreas Fault, had a maximum movement of 6 metres (20 feet) during the 1906 San Francisco earthquake is a 1300km Dextral strike-slip fault ✔ North Anatolian Fault, during the İzmit earthquake of 1999, moved more than 2.5 metres (8.1 feet) is a Dextral Strike Slip Fault ✔ Palu-Koro Fault in Indonesia is a 500km Sinistral strike-slip fault caused M7.5 Sulawesi Earthquake in 2018 ✔ Septentrional-Orient Fault Zone is an active Sinistral strike-slip fault in the Caribbean. 1842 Earthquake in Cap Haitien(M8.1) ✔ Marikina Valley Fault System : Dextral Strike Slip ✔ 1855 Wairarapa Fault rupture, combination of reverse and dextral movement. MERCALLI AND RICHTER SCALE: ϕμ_αρδνασαχ / σκνλαζο 46 | Page ENGINEERING CONSIDERATION FOR EARTHQUAKE ▪ timeandintensityoftheearthquakecanneverbepredicted ▪ Remedyistoprovideadditionalfactorsinthedesignofstructuretominimizethe losses due to shocks of an earthquake ▪ collectsufficientdata,regardingthepreviousseismicactivityinthearea ▪ assessthelosses,whicharelikelytotakeplaceinfurnitureduetoearthquake shocks ▪ provide factors of safety, to stop or minimize the loss due to sever earth shocks PRECAUTIONS to make building earthquake resilient ✔ foundationshouldrestonafirmrockbed ✔ Grillagefoundationspreferablybeprovided ✔ Excavationoffoundationmustbeuptosamelevelthroughoutthebuilding ✔ concreteshouldbelaidinrichmortarandcontinuous ✔ Masonrymustbeinmax1:4cementmortarratio ✔ R.Cslab,cantilevers,projections,parapets,domesshouldbeprovided ✔ Allpartsofbuildingmustbetiedfirmlywitheachother ✔ Building should be uniform height ✔ Bestmaterialsshouldbeused. ϕμ_αρδνασαχ / σκνλαζο 47 | Page ELABORATE Watch: PlateTectonics: https://youtu.be/RA2-Vc4PIOY Tectonic Plate Movement: https://youtu.be/f4V4amhLZdU TransformBoundaries: https://youtu.be/QE_RC6gqT3w ConvergentBoundaries: https://youtu.be/L2XixysJgPs DivergentBoundaries: https://youtu.be/wfHwAeVNrzA Groundwater: https://youtu.be/zyHtkDCwQUw WindErosion: https://youtu.be/PQmon7Rj6ns Aquifers: https://vimeo.com/288326731 Earthquakes: https://youtu.be/T0AEtX-uPLA Answer Quiz given by course facilitator. EVALUATE Tectonic Plates: Make a research on the tectonic plates found in Asia. 1. You are required to submit a geological map identifying the different plates. 2. Includeaninformationsheetaboutdetailsoftheplates. a. Location b. Area c. Evolution d. Otherimportantinformation 3. Providethereferencesattheendofyourresearch. 4. Avoidplagiarism.Correspondingdeductionswillbeapplied. 5. Files shall be placed in docx files, ppt or pdf. Since your creativity is graded, you can use any appropriate font, but the minimum size should be 12. This is not to be taken like a photo album or scrapbook. Make it professional looking like an engineer’s presentation. Earthquake: Make a presentation about the different fault lines in the Philippines. 1. Youarerequiredtosubmitageologicalmapidentifyingthedifferentfaultlines 2. Includeaninformationsheetaboutdetails: a. Location b. Length c. Movement d. Otherimportantinformation 3. Providethereferencesattheendofyourresearch. 4. Avoidplagiarism.Correspondingdeductionswillbeapplied. 5. Files shall be placed in docx files, ppt or pdf. Since your creativity is graded, you can use any appropriate font, but the minimum size should be 12. This is not to be taken like a photo album or scrapbook. Make it professional looking like an engineer’s presentation. ϕμ_αρδνασαχ / σκνλαζο 48 | Page Answer Exam given by course facilitator ϕμ_αρδνασαχ / σκνλαζο 49 | Page  MODULE 2: MINERALOGY ENGAGE In your own opinion, how are minerals formed? Why is it important for CE students to understand the qualities of minerals? What are the most common minerals found in CE construction materials? Discuss fossil fuels. EXPLORE MINERALOGY Scientific study of minerals, Structure (chemical and crystalline),Properties (physical), Processes (origin, formation & occurrence), Classification and distribution, and uses MINERALS - This are naturally occurring, inorganic, solid element or compound crystalline substance, has definite atomic structure and chemical composition - over4000Mineralsexistinearthcrust - Allarecomposedofoxygen,silicon,aluminum,iron,calcium,potassium,sodium and magnesium CLASSIFICATIONS AND MINERAL GROUPS ▪ ROCK FORMING MINERALS ▪ Mineralsfoundinabundanceofearthcrust ▪ formsigneous,sedimentary,ormetamorphicrocks ▪ ORE FORMING MINERALS ▪ Mineralsthatareofeconomicvalues ▪ limitedmodeofoccurrence ▪ formedbymoreunusualprocesses ϕμ_αρδνασαχ / σκνλαζο 50 | Page  MINERAL GROUP ANIONS Exception OXIDES O2- Carbon, sulphur and silicate SULPHIDES S-2 SULPHATES SO –24 HALIDES Halogens (F, Cl, Br, etc) CARBONATES CO–23 complex PHOSPHATES PO–34 complex SILICATES Si: O2 Combination of silicon and Si:O4 oxygen Single elements NATIVE MINERALS PHYSICAL PROPERTIES OF MINERALS 1. COLOR - Not constant in most of the minerals - Due to the stain or impurities in the minerals - May indicate that mineral has undergone peculiar phenomena PLAY OF COLORS: - Development of series of prismatic colors by turning about in light CHANGE OF COLORS: - Similar to play of colors but slower rotation IRIDESCENE: - Show rainbow colors either in the interior or on the surface 2. STREAK - Color of mineral powder - Nearly constant than the color - Determined by marking unglazed porcelain or simply by scratching with a knife and observing the powder color 3. LUSTRE - Description of how much a mineral reflects light a. METALLIC(SHINY) i. Classy(vitreous)–likebrokenglass ii. Metallic–likemetal iii. Pearly–likepearls b. NONMETALLIC(DULL) ϕμ_αρδνασαχ / σκνλαζο 51 | Page 4. STRUCTUREANDFORM(HABIT) - Denote the shape and form of minerals PRISMATIC HOPPER –elongatedinonedirectionlikeprism –edgesarefullydevelopedbut TABULAR interiorspacesarenotfilled;hollow –tabularorplatelikeshape PLUMOSE EQUANT –fine,featheryscalesresembling –possessapproximatelysameside plumes lengthinexerydirection BLADED: FOLIATED –bladelikestructure,elongated,flat –thinsheets,flakes,orscales crystalslikeknifeblades FIBROUS RADIATED: –crystalaggregatesresemblinglong, –fibrousdivergingfromcentralpoints slender needles, hair or threadlike LAMELLAR: fibers –madeofseparableplates;feathery RETICULATED ordelicateaggregates – aggregate of crystals forming a COLLOFORM–Spherical,roundedor networkorlattice bulbousshape STELLATED BOTRYOIDAL: – composed of branches which –anaggregate-likebunchofgrapes radiatestarlikefromacentralpoint orglobular DENDRITIC RENIFORM: – divergent branching and treelike –kidneyshapedaggregate mineralgrowth MAMILLARY COLUMNARorSTALACTITIC: –displaysoft,roundedcurves –thickorthincolumn-likestructure; STRIATED: Micaceous: -displayshallowparallelgroovesor -thin,flatsheetsorflakesthateasily linesalongflatcrystalfaces peelsorsplitoffalargermass GRANULAR: ACICULAR–containsmanylong, –Denselypackedgrains slendercrystalswhichmayradiatelike MASSIVE: needlesorbristlesfromcommonbase; –Nodefiniteshapeforminerals;large longnarrowlikepineleaf andlumpy FILIFORM–exhibitsmanyhairlikeor threadlike filaments 5. HARDNESS - Resistance of minerals to abrasion or scratching - Measured relative to a scale of ten of minerals 6. SPECIFICGRAVITY - the density of the mineral compared to the density of water - metallic minerals have high SG, non-metallic minerals have lower SG ϕμ_αρδνασαχ / σκνλαζο 52 | Page  MohsHardnessScale SpecificGravityofCommonMinerals 7. CLEAVAGE - tendency of a crystallized mineral to break along certain definite planes yielding more or less smooth surfaces -cubic:3cleavages -Dodecahedral:6cleavage -octahedral:4cleavages -Basal:1cleavage 8. FRACTURE - defined as the appearance of its broken surface a. CONCHOIDAL:concentricringsorcurvedsurface b. EVEN:smoothandflat c. UNEVEN:irregularsurface d. SPLINTERY:breakswitharough 9. TENACITY - Behavior of mineral when deformed or broken SECTILITY: Minerals may be cut with a knife MALLEABILITY: The mineral may be pounded out into thin sheets BRITTLENESS: The mineral breaks or powders easily ELASTICITY: Regains former shape as pressure is released DUCTILITY: Mineral may be drawn into a wire; tough as well PLASTICITY: Mineral will not go back to original position when released CRYSTALLOGRAPHY AND CRYSTALLINE SYSTEMS CRYSTALLOGRAPHY - thescienceconcernedwiththeformation,properties,andstructureofcrystals - dealswiththegeometricformsofcrystals MINERAL CRYSTAL SYSTEM - alsocalledMineralHabits - referstothewaycrystalsformwithinaspecificmineral ϕμ_αρδνασαχ / σκνλαζο 53 | Page  e.g. Diamond: twopyramidsattachedattheirbases Quartz: hassixsides CRYSTAL FORMS: ▪ internalatomicarrangementofmineralmanifestedoutwardlybydevelopmentof geometrical shapes or crystal characters 3 TYPES OF CRYSTAL FORM Crystallized ▪ mineraloccursintheformofwell-definedcrystals Amorphous ▪ showsabsolutelynosignsorevidenceofcrystallization Crystalline ▪ well-definedcrystalsareabsentbutatendencytowardscrystallizationispresent SYMMETRY AND LATTICES SYMMETRY ▪ Describestherepetitionofstructuralfeatures 2 GENERAL TYPES: Translational ▪ Periodicrepetitionofstructuralfeatureacross alengthorthroughanareaor volume Point Periodicrepetitionofstructuralfeatureatapoint ▪ ▪ Reflection,rotation,andinversionareexamplesofpointsymmetry LATTICES ▪ Directlyrelatedtotranslationalsymmetry ▪ Anetworkorarraycomposedofsinglemotifthathasbeentranslatedandrepeatedat fixed intervals throughout the space ▪ BravaisLattice ▪ Thereareonlyfourteen(14)differentlatticesthatmaybeformedina3Dspace ▪ Dividedintosix(6)crystalsystems ▪ Hasthree(3)types: ▪ Primitive ▪ Facecentered ▪ Body-centered CRYSTAL SYSTEMS - Allmineralsformcrystalsinoneofthesystemsandaredefinedbyacombinationof three factors: 1.Numberofaxis 2.Lengthofaxis 3.Anglestheaxesmeet - AxisAisusuallytheshortest,whileCisthelongestaxis ϕμ_αρδνασαχ / σκνλαζο 54 | Page CRYSTAL FORMS ▪ Setoffacesthataregeometricallyequivalentandwhosespatialpositionsarerelated to one another according to symmetry ▪ Eachcrystalsystemsmayobtaindifferentcrystalforms ϕμ_αρδνασαχ / σκνλαζο 55 | Page ▪ Types of Crystal forms: ▪ Monohedron ▪ Prism ▪ Scalenohedron ▪ Parallelohedron ▪ Pyramid ▪ Rhombhohedron ▪ Dihedron ▪ Dipyramid ▪ Tetrahedron ▪ Disphenoid ▪ Trapezohedron MINERAL FAMILIES QUARTZ FAMILY ▪ German“quarz”meaninguncertainorigin ▪ Wordcrystalwasoriginallyusedonlyforquartz ▪ Animportantrockformingmineralnexttofeldspar ▪ Anon–metallicrefractorymineral–havehighmeltingpoints ▪ MemberoftheSILICATEmineralgroup CHEMISTRY: COMPOSITION: ▪ ChemicalFormula: SiO2 ▪ Silicon: 46.74% ▪ MolecularWeight: 60.08g ▪ Oxygen: 53.26% FORMATION: ▪ Formedbycrystallizationofsilica-richmoltenrock(magma) ▪ Formedinpegmatitesduringandafterpneumatolyticprocesses(metamorphic process due to hot vapors) ▪ Growinhotwaterysolutions(hydrothermalenvironments)between100Cto 450C, often at very high pressure PHYSICAL PROPERTIES ▪ CRYSTALSYSTEM:Hexagonal ▪ HARDNESS:7 ▪ HABIT:CrystallineorArmophous ▪ TENACITY:Brittle ▪ CLEAVAGE:indistinct ▪ SPECIFICGRAVITY:2.6–2.7 ▪ FRACTURE:Conchoidal ▪ STREAK:White ▪ ▪ COLOR:Pure-Colorless,Colored- ▪ TRANSPARENCY: Transparent/ indicateimpurities Semi-transparent/Opaque LUSTER:vitreous POLYMORPHIC TRANSFORMATION: Quartz, tridymite, cristobalite, moganite, coesite, keatite OCCURRENCE: Mostly found in igneous, sedimentary and metamorphic rocks USE: used in the glassmaking industry FELDSPAR FAMILY ▪ Came from German word “feldspat” meaning a rock that does not contain a core ▪ Mostabundantofallminerals ▪ Composesmorethan50%oftheearth’scrustbyweight ▪ Non-metallicandsilicate ϕμ_αρδνασαχ / σκνλαζο 56 | Page ▪ Chemical Formula: ▪Plagioclase: NaAlSi3O8 ▪ Potassium Feldspar (Alkali Feldspar): K Al Si3O8 (orSoda-limeFeldspar) CaAl2Si2O8 OCCURRENCE: crystallize from magma as both intrusive and extrusive igneous rocks and are also present in many types of metamorphic rock; also found in many types of sedimentary rocks USE: a common raw material used in glassmaking, ceramics, and to some extent as a filler and extender in paint, plastics, and rubber; alumina from feldspar improves product hardness, durability, and resistance to chemical corrosion. In ceramics, the alkalis in feldspar act as a flux, lowering the melting temperature of a mixture. consumed in glassmaking, including glass containers and glass fiber PLAGIOCLASE PHYSICAL PROPERTIES: ▪ CRYSTAL SYSTEM: Triclinic ▪ LUSTER: ▪ HABIT: Tabular (Crystalline) Vitreous usually pearly ▪ CLEAVAGE: ▪ HARDNESS: 6 - 6.5 Perfect – 2Directional ▪ TENACITY: brittle ▪ FRACTURE: Conchoidal ▪ SPECIFIC GRAVITY: 2.6 – 2.8 ▪ COLOR: white to dark gray ▪ TRANSPARENCY: ▪ STREAK: white translucent to transparent ORTHOCLASE: PHYSICAL PROPERTIES: CRYSTALSYSTEM: Monoclinic LUSTER: Vitreous, pearly CRYSTALHABIT: HARDNESS: 6 CLEAVAGE:perfect Tenacity: Brittle FRACTURE: SPECIFIC GRAVITY: Uneven, Conchoidal 2.55–2.63 COLOR: Colourless, greenish, TRANSPARENCY: greyish yellow, white, pink Translucent to member of the alkali STREAK: White transparent feldspar series PYROXENE GROUP ▪ An important group of rock forming minerals ▪ occur in dark colored igneous and metamorphic rocks ▪ Rich in calcium, magnesium, iron and silicates ▪ Show a single chain structure of silicate ϕμ_αρδνασαχ / σκνλαζο 57 | Page ▪ Classifiedinto ▪ ORTHOPYROXENE CLINOPYROXENE ▪ Enstatite: MgSiO3 ▪ Augite: (Ca,Na)(Mg,Fe,Al)(Al,Si)2O6 ▪ Hyperthene: (Mg,Fe)SiO3 ▪ Diopside: CaMgSi2O6 ▪ Hedenbergite: CaFeSi2O6 PHYSICAL PROPERTIES: PYROXENE - AUGITE ▪ CRYSTALSYSTEM:Monoclinic ▪ LUSTER:Vitreous(cleavageandcrystal ▪ HABIT:Crystalline surface);dull(onothersurface) ▪ ▪ CLEAVAGE:Good(prismatic) HARDNESS:5.5–6.0 ▪ ▪ FRACTURE:Conchoidal TENACITY:brittle ▪ ▪ COLOR:Greyishgreenandblack SPECIFICGRAVITY:3.2–3.6(Medium) ▪ ▪ STREAK:white TRANSPARENCY:Translucent/Opaque OCCURRENCE: Occurs in ferro magnesium mineral of igneous rock For AUGITE: commonly occurs in mafic and intermediate igneous rocks such as basalt, `gabbro, andesite, and diorite HORNBLENDE Principalcomponent AComplex inosilicate seriesof minerals ofamphibole Thegeneralformula: PHYSICAL PROPERTIES (Ca,Na)2–3(Mg,Fe,Al)5(Al,Si)8O22(OH,F)2 ▪ CRYSTALSYSTEM:Monoclinic ▪ HARDNESS:5-6 ▪ HABIT:Hexagonal,granular ▪ SPECIFICGRAVITY:2.9 ▪ CLEAVAGE:imperfect ▪ STREAK:colorless,whitetopalegray ▪ FRACTURE:uneven ▪ TRANSPARENCY: ▪ COLOR:black,DarkGreentoBrown Translucent/Opaque ▪ LUSTER:Vitreoustodull OCCURRENCE: common constituent of many igneous and metamorphic rocks such as granite, syenite, diorite, gabbro, basalt, andesite, gneiss, and schist USE: crushed hornblende is used for highway construction and as railroad ballast; cut hornblende is use as dimension stone MICA GROUP ▪ Formsheetlikestructure ▪ Canbesplitintoverythinsheetsalongonedirection ▪ RichinAluminumandmagnesium ▪ Occupy4%ofearth’scrust MICA – BIOTITE ▪Group of black mica K(Mg,Fe)3(AlSi3)O10(F,OH)2 minerals PHYSICALPROPERTIES: ▪ Chemical Composition: ϕμ_αρδνασαχ / σκνλαζο 58 | Page CRYSTALSYSTEM: darkbrowntoblack,white STREAK: Monoclinic LUSTER:Vitreoustopearly whitetogrey,flakes HABIT: HARDNESS:2.5–3.0 produced Prismatic,massivetoplaty SPECIFICGRAVITY: TRANSPARENCY: CLEAVAGE:Basal,Perfect 2.7–3.4 Transparent/Translucent FRACTURE:micaceous TENACITY: COLOR: brittletoflexible,elastic OCCURRENCE: Found mostly in igneous and metamorphic rocks USE: used extensively to constrain ages of rocks, by either potassium-argon dating or argon–argon dating; useful in assessing temperature histories of metamorphic rocks MICA – MUSCOVITE PHYSICAL PROPERTIES: ▪CRYSTALSYSTEM: ▪LUSTER:PearlytoVitreous Monoclinic ▪HARDNESS:2.5–3.0 ▪HABIT:Massive,Platy ▪TENACITY:Elastic ▪CLEAVAGE:Perfect ▪SPECIFICGRAVITY: ▪FRACTURE:Micaceous ▪2.8–2.9 ▪COLOR: ▪STREAK: blackorbrown(thick) ▪white,oftenshedsflakes ▪ most common mineral of colorless with tint of ▪TRANSPARENCY: the mica family Transparent/Translucent yellow, brown or rose ▪ chemical composition: (thin) ▪ KAl2(Si3AlO10)(OH)2 OCCURRENCE: presentinigneous,metamorphic,andsedimentaryrocks ▪ Formedduringregionalmetamorphosisoargillaceousrocks USES: Used chiefly as an insulating material in the manufacture of electrical apparatus Used as a transparent material, isinglass, for stove doors, lanterns, etc. CALCITE ▪ Arockformingmineral ▪ Consideredan“ubiquitousmineral”–found principal constituent of limestone and ▪ A everywhere marble ▪ Serves as one of the largest carbon repositories on Earth ▪ ChemicalFormula:CaCO3 ϕμ_αρδνασαχ / σκνλαζο 59 | Page PHYSICAL PROPERTIES: ▪ CRYSTALSYSTEM:Hexagonal ▪LUSTER:Vitreous ▪ HABIT:Rhombohedral3D ▪HARDNESS:3.0 ▪ CLEAVAGE:Perfect ▪ TENACITY:brittle ▪ FRACTURE:Conchoidal ▪ SPECIFICGRAVITY:2.7 ▪ COLOR: ▪ STREAK:white usually white, colorless, grey, red, ▪ TRANSPARENCY:Transparentto green,blue,yellow,brown,orange Translucent OCCURRENCE: occurs in major rock-forming minerals such as limestones, marbles, and chalks USES: as a construction material, abrasive, agricultural soil treatment, construction aggregate, pigment, pharmaceutical and more GARNET FAMILY ▪ ArockformingmineralundertheSilicateGroup ▪ Share common crystal structure and generalized chemical composition ▪ ChemicalFormula:X3Y2(SiO4)3 ▪ X may be Calcium, Magnesium, iron or Magnesium ▪ Ymaybealuminum,Iron,Manganese,vanadium or Chromium PHYSICAL PROPERTIES: ▪ CRYSTALSYSTEM:Isometric ▪LUSTER:Vitreoustosubadamantine ▪ HABIT: Rhombic dodecahedron or ▪ HARDNESS:6.5–7.5 cubic ▪ SPECIFICGRAVITY:3.1–4.3 ▪ CLEAVAGE:None ▪ STREAK:whitetocolorless ▪ FRACTURE:conchoidaltouneven ▪ TRANSPARENCY:Transparentto ▪ COLOR:virtualallcolors,rarelyblue Translucent OCCURRENCE and FORMATION: most common in metamorphic rocks. A few occur in igneous rocks, especially granites and granitic pegmatites USES: widely used as a gemstone; crushed garnet is used to make abrasives COAL AND PETROLEUM COAL – a combustible sedimentary rock formed through the process “coalification” – formed from ancient vegetation which has been consolidated between other rock strata and transformed by the combined effects of microbial action, pressure and heat over considerable time period 60 | Page ϕμ_αρδνασαχ / σκνλαζο – occurs as layers or seams, ranging in thickness; composed mostly of carbon, hydrogen, oxygen and smaller amounts of nitrogen, Sulphur and other elements; also contains water and particles of other inorganic matter – broadly separated into brown and black which have different thermal properties and uses BROWN COAL (lignite) – has low energy and high ash content – Unsuitable for export and us used to generate electricity in power stations located at or near the mine BLACK COAL – Harder than brown coal and has higher energy content ▪ Thermal(steaming)coal ▪ Used mainly for generating electricity in power stations where it is pulverized and burnt to heat steam generating boilers ▪ Metallurgical(coking)coal ▪ Suitableformakingcokeusedinproductionofpigiron ▪ HavelowSulphurandphosphorouscontentsandrelativelyscarce ▪ Attracthigherpricethanthermalcoals ▪ Coalreservesarediscoveredthroughexplorationswhichinvolvesextensiveuseof geophysical surveys ▪ Minedbybothsurfaceor‘opencut’(opencast)andunderground(deep)mining methods depending on the local geology of deposit ▪ Undergroundmining–accounts60%ofworldcoalproduction ▪ Opencutmining–economicwhencoalseam(s)isnearthesurface PETROLEUM – called mineral oil, obtained from sedimentary rocks of earth – an inflammable liquid composed of hydrocarbons which constitute to 90 – 95% of petroleum, remaining are organic compounds consisting of oxygen, nitrogen, Sulphur and races of organo-metallic compounds CRUDE PETROLEUM – consists of mixture of hydrocarbons (solid, liquid and gaseous) – includes compounds belonging to paraffin and some unsaturated hydrocarbons and small proportion of benzene group UTILIZATION OF PETROLEUM: - MainlyusedasmotivepowerandUtilizedintransportation - easilytransportedfromtheproducingareastotheconsumingareaswiththe help of tankers and more conveniently, efficiently, and economically by pipelines - emitsverylittlesmokeandleavesnoashanduseduptothelastdrop - providesthemostimportantlubricatingagentsandisusedasanimportantraw material for various Petro-chemical products Origin and Occurrence ϕμ_αρδνασαχ / σκνλαζο 61 | Page – has an organic origin and is found in sedimentary basins, shallow depressions and in the seas (past and present) – Most of the oil reserves in India are associated with anticlines and fault traps in the sedimentary rock formations of tertiary times, about 3 million years ago – Oil and natural gas originated from animal or vegetable matter contained in shallow marine sediments, such as sands, silts and clays deposited during the periods when land and aquatic life was abundant in various forms, especially the minor microscopic forms of flora and fauna – Conditions for oil formation were favourable especially in the lower and middle Tertiary period – Denseforestsandseaorganismsflourishedinthegulfs,estuaries,deltas,andtheland surrounding them during this period – decompositionoforganicmatterinthesedimentaryrockshasledtotheformationofoil – Note:Thoughoilismainlyfoundinsedimentaryrocks,allsedimentaryrocksdonot contain oil PRE-REQUISITE CONDITIONS OF OIL RESERVOIR (i) porositytoaccommodatesufficientlylargeamountsofoil (ii) permeability to discharge oil and/or gas when well has been drilled. (iii) the porous sand beds sandstone, conglomerates of fissured limestone containing oil should be capped by impervious beds so that oil does not dissipate by percolation in the surrounding rocks Reserves: - IndianMineralYearbook1982estimatedareserveof468milliontonsofwhich328 million tons was available in Mumbai High - In1984,thereserveswereestimatedat500milliontons - TheIndianPetroleumandNaturalGasStatisticsputthetotalreservesofcrudeoilat 581.43 million tons in 1986-87 - prognosticatedhydrocarbonresourcebaseinIndiansedimentarybasinsincluding deep water has been estimated at about 28 billion tons - onlyaboutone-fourthofhydrocarbonreserveshavebeenestablishedason1April - 2002 - About70percentoftheestablishedhydrocarbonreservesisoilandrestaregas recoverablehydrocarbonreservesareoftheorderof2.6billiontons Production: - IndiawasaveryinsignificantproducerofpetroleumatthetimeofIndependenceand remained so till Mumbai High started production on a large scale - off-shore production did not start till the mid-1970s and the entire production was received from on-shore oil fields - In1980-81abouthalfoftheproductionofcrudeoilcamefromon-shorefieldswhilethe remaining half was received from the off-shore resources - off-shoreproductionincreasedatamuchfasterratethantheon-shoreproduction - abouttwo-thirdsofproductionofcrudeoilisprovidedbytheoff-shorefieldsformore than two decades Petroleum Refining: ϕμ_αρδνασαχ / σκνλαζο 62 | Page - Oilextractedfromtheoilwellsisinitscrudeformandcontainsmanyimpurities - Itisrefinedinoilrefineriesbeforeuse - afterrefining,variousproductssuchaskerosene,diesel,petrol,lubricants,bitumen,etc. are obtained - India’sfirstoilrefinerystartedworkingwaybackin1901atDigboiinAssam,itremained the only refinery in the whole of India for more than half a century Imports: - ConsumptionofoilanditsproductshasalwaysoutstrippedproductioninIndia - In1950-51,Indiaproducedonly2,700,000tonsofoilagainstconsumptionof3,400,000 tons. - needforoilhasincreaseddramaticallyinthepost-independenteraasindustriesand transport progressed - importsofoilweremorethanthreetimestheindigenousproduction. EXPLAIN MINERAL PROPERTIES: ϕμ_αρδνασαχ / σκνλαζο 63 | Page ϕμ_αρδνασαχ / σκνλαζο 64 | Page ϕμ_αρδνασαχ / σκνλαζο 65 | Page ϕμ_αρδνασαχ / σκνλαζο 66 | Page ϕμ_αρδνασαχ / σκνλαζο 67 | Page MINERAL SYSTEMS: 1. ISOMETRICSYSTEM:BASICSHAPE ϕμ_αρδνασαχ / σκνλαζο 68 | Page 2. ORTHORHOMBICSYSTEM:BASICSHAPE ϕμ_αρδνασαχ / σκνλαζο 69 | Page 3. TETRAGONAL SYSTEM: BASIC SHAPE 4. MONOCLINICSYSTEM:BASICSHAPE 5. TRICLINIC SYSTEM BASIC SHAPE ϕμ_αρδνασαχ / σκνλαζο 70 | Page 6. HEXAGONAL SYSTEM: BASIC SHAPE MINERAL GROUPS: MINERAL GROUP Common Name CHEMICALNAME ChemicalFormula Hematite IronOxide Fe2O3 OXIDES Corundum AluminumOxide Al2O3 Frozen Water H2O Galena LeadSulphide PbS SULPHIDES Pyrite IronSulphide FeS2 Gypsum CalciumSulphate CaSO4⋅H2O SULPHATES Barite BariumSulphate BaSO4 Fluorite CalciumFluoride CaF2 HALIDES Halite SodiumChloride NaCl Calcite CalciumCarbonate CaCO3 CARBONATES Calcium- Magnesium (Ca,Mg)CO3 Dolomite Carbonate ϕμ_αρδνασαχ / σκνλαζο 71 | Page  Apatite Ca5(PO4)3(OH) PHOSPHATES Hydrated Copper CuAl6(PO4)4(OH)8 Turquoise Aluminum Phosphate ⋅5H2O Quartz Silicon Oxygen Tetrahedra SiO2 Sodium-Aluminum Feldspar NaAlSi3O8 SILICATES Silicate Iron Olivine Silicateor magnesium (Mg,Fe)2SiO4 Gold Au Diamond Carbon C NATIVE MINERALS Graphite Carbon C Sulphur S Copper Cu MINERAL FAMILIES: ϕμ_αρδνασαχ / σκνλαζο 72 | Page ϕμ_αρδνασαχ / σκνλαζο 73 | Page ϕμ_αρδνασαχ / σκνλαζο 74 | Page ELABORATE Watch: Introduction to Mineralogy: https://youtu.be/8a7p1NFn64s Physical Properties: https://youtu.be/yjubWww5dI4 Crystal Structure: https://youtu.be/PgSRAsgrKmg Coal and Petroleum: https://youtu.be/iubWN1cnwIs or https://youtu.be/zaXBVYr9Ij0 Answer Quiz given by facilitator EVALUATE Research on the different uses of the various mineral families. Here are guide questions to help you proceed with the presentation: a) Howdothemineralslooklike? b) Howaretheyusedindailylife? c) Aretheyusedinengineeringactivities? 1. Providethereferencesattheendofyourresearch. 2. Avoidplagiarism.Correspondingdeductionswillbeapplied. 3. Files shall be placed in docx files, ppt or pdf. Since your creativity is graded, you can use any appropriate font but the minimum size should be 12. This is not to be taken like a photo album or scrapbook. Make it professional looking like an engineer’s presentation. Write an essay about the following: Which properties are the most helpful in identifying minerals. Are these properties helpful in the field of engineering? 1. Youressayshouldbewithin400to500words. 2. Ifyoufinditnecessarytoaddsomeimages,youareallowed. 3. Followtheproperessayformat: i. Introduction ii. Firstbodyparagraph iii. Secondbodyparagraph…andsoon iv. Conclusion 4. Avoidplagiarism.Correspondingdeductionswillbeapplied. 5. Files shall be placed in docx files. Use 1 inch margin all around, Arial 12 justified. and place your name in the header. Provide your code of honesty at the end of your submittal. Answer exam given by facilitator MODULE 3: PETROLOGY ϕμ_αρδνασαχ / σκνλαζο 75 | Page ENGAGE How are rocks formed? Where do you think rock come from? What do you think is the best rock for concrete aggregates? Explain your opinion. When doing finishing works, which rock is more preferred – granite or marble? EXPLORE PETROLOGY From Greek “petra” meaning rock and “logos” study A branch of geology that studies the origin, composition, distribution, and structure of rocks LITHOLOGY ▪ Specializationofpetrologythatfocusesonmacroscopichandsampleoroutcropscale description of rocks PETROGRAPHY ▪ Specialtythatdealswithmicroscopicdetailsofrocks PETROGENESIS ▪ Abranchofpetrologydealingwiththeoriginandformationofrocks(involvesa combination of mineralogical, chemical, and field data). BRANCHES OF PETROLOGY 1. IGNEOUSPETROLOGY - Focuses on the composition and texture of igneous rocks such as granite or basal 2. SEDIMENTARYPETROLOGY - Focuses on the composition and texture of sedimentary rocks such as sandstone, shale, or limestone 3. METAMORPHICPETROLOGY - Focuses on composition and texture of metamorphic rocks such as slate, marble, gneiss or schist 4. EXPERIMENTALPETROLOGY ϕμ_αρδνασαχ / σκνλαζο 76 | Page  - Employs high pressure, high temperature apparatus to investigate geochemistry and phase relations of natural or synthetic materials at elevated pressures and temperature METHODOLOGY: - Utilizes classical fields of mineralogy, petrography, optical mineralogy and chemical analyses to describe composition and texture of rocks - Modernpetrologistincludeprinciplesofgeochemistryandgeophysicsthroughstudies of geochemical trends and cycles and use the thermodynamics data and experiments to better understand the origins of rocks IGNEOUS PETROLOGY IGNEOUS ROCK any crystalline or glassy rock that forms from cooling of a magma CONDITIONS FOR ORIGINAL MATERIAL very high temperature and at molten state COMPOSITION: 1. Igneousrocksareformedbothfrommagmaandlava 2. hotmoltenmaterialoccurringnaturallybelowtheEarthsurfaceiscalledmagma 3. Magmaeruptedthroughvolcanoesiscalledlava 4. Magmaisactuallyahypotheticalmelt 5. Lavaisamaterialthathaspouredoutoccasionallyfromvolcanoesinmanyregions of the world again and again 6. Magmaorlavafromwhichigneousrocksareformedmaynotbeentirelyapure melt: it may have a crystalline or solid fraction and also a gaseous fraction thoroughly mixed with it 7. Solidandgaseousfractionsformonlyasmallpartofthemagmaorlava,whichare predominantly made up of liquid material igneous rock. DIFFERENCE IN MOLECULAR CONCENTRATION o Magmaisreachinmoleculesofparticularmineralithasbetterchancetogrowintobig crystals which may be embedded in fine-grained mass resulting from deficient components RELATIVE INSOLUBILITY o Crystalgrainsgetenlargedwhereascrystalsofothersolublecontentsgetmixedup again with magma o Solublecontentsmakeupthegroundmasscrystallizingtowardtheend CHANGE IN PHYSICO-CHEMICAL CONDITIONS ϕμ_αρδνασαχ / σκνλαζο 77 | Page o Abrupt and discontinuous changes in textures result in formation of unequal crystal dimensions o Magmacrystallizingatgreatdepthsmayproducewell-definedlargecrystals o Whensamemagmamovesupward,pressureandtemperatureactingonitisgreatly reduced o Crystallization in the upper levels of magma becomes very rapid resulting in fine-grained matrix containing the larger crystals formed earlier CHARACTERISTICS OF MAGMA: Types of Magma are determined by chemical composition of the magma TEMP, VISCOSIT TYPE %Wtof Fe,Mg,Ca K,Na GAS °C Y Pa-sec SiO2 composition Composition CONTENT Low BASALTIC 1000– 45–55 High Low 1200 10–10 3 MAGMA ANDESITIC 55–65 Intermediate Intermediate Intermediate800–1000 103–105 MAGMA RHYOLITIC MAGMA 65 – 75 Low High High 650 – 800 105 – 109 CLASSIFICATION OF IGNEOUS ROCKS Igneous rocks are classified into two main categories: 1. basedontheproportionofsilicaasmainconstituent 2. basedonthebasisofsolidificationofmagma CLASSIFICATION BASED ON SILICA The content of silica (as SiO2) in igneous rocks varies from over 80% to about 40% and results in some. These were considered to be 'salts' of silicic acids. 1. ACIDICROCKS Igneousrockshavinghighpercentageofsilica(morethan2/3). Theyarecompositionallyrickinsilica,aluminaandalkalis,butarepoorincalcium, magnesium and iron. Theyarecomposedofquartz,alkalifeldsparandmuscovitemica-representingthe late stage of crystallization of magma. Theserocksarelightincolorandweight. ϕμ_αρδνασαχ / σκνλαζο 78 | Page  2. BASIC ROCKS Igneous rocks which contain relatively low percentage of silica (generally less than 50%) These rocks are dark in color and heavier than acidic rocks. CLASSIFICATION ON THE BASIS OF SOLIDIFICATION OF MAGMA a. VOLCANICROCKS ▪ Also called extrusive rocks ▪ Formed on Earth’s surface by cooling and crystallization of lava ▪ grain size of crystals formed in these rocks is very fine, often microscopic ▪ cooling of lava may take place on the surface or even under waters of seas and oceans b. PLUTONICROCKS ▪ Also called intrusive rocks ▪ Formed beneath the Earth’s surface, generally 7 – 10 km deep ▪ Coarse grained due to slow cooling rate ▪ These rocks get exposed on the surface of the earth as a result of erosion of the overlying strata ϕμ_αρδνασαχ / σκνλαζο 79 | Page  ▪ Examples: Granites, Syenites, and Gabbros c. HYPABBYSALROCKS ▪ formed at intermediate depths, generally up to 2 kms below the surface of the earth ▪ exhibit mixed characteristics of volcanic and plutonic rocks ▪ Examples: Porphyries of various compositions TEXTURE OF IGNEOUS ROCKS - mutualrelationshipofdifferentmineralogicalcomponentinarock - determinedbythesize,shapeandarrangementofcomponentswithinthebodyofthe rock Factors Affecting Texture ▪ Rateofcooling ▪ Fabric ▪ Dimension ▪ DegreeofCrystallization ▪ Shapeorform ▪ Granularity TYPES OF TEXTURE 1. EQUIGRANULARTEXTURE ▪ Majorityofcrystalcomponentsofrockarebroadlyequalinsize ▪ Shownbygranitesandfelsites ▪ Granitictexture ▪ eitherallcoarse-grainedorallmedium-grained ▪ euhedraltosubhedraloutlines ▪ Felsitictexture ▪ microgranularandshowperfectoutlines ▪ Maybedescribedasequiangularandpanidiomorphic ▪ Orthophyrictexture ▪ Betweengraniticandfelsitictextures ▪ Individualgrainsareafineinsizebutmicrogranular 2. INEQUIGRANULARTEXTURE ▪ Majorityofconstituentmineralsshowmarkeddifferenceinrelativegrainsized ▪ ClassifiedasPorphyriticandpoiklitictextures ▪ PorphyriticTexture ▪ Large crystals set in finer-grained or glassy groundmass; larger crystals (phenocryst) forms earlier in crystallization sequence ▪ ▪ PoikliticTexture ▪ Largecomponentcrystalscontainsmallercrystalsotherthanmineralswithin them 3. DIRECTIVE TEXTURE ϕμ_αρδνασαχ / σκνλαζο 80 | Page  ▪ Indicateresultofflowofmagmaduringformationofrocks ▪ Exhibitperfectorsemiperfectparallelismofcrystalsinthedirectionofmagmaflow ▪ Commonexamplesare: ▪ Trachytic ▪ Characteristic of certain feldspathic lavas recognised by parallel arrangement of feldspar crystals ▪ Trachytoid ▪ Foundinsomesyenites 4. INTERGROWTHTEXTURE ▪ Twoormoremineralscrystallizeoutsimultaneouslyinalimitedspaceresultingto mixed up or intergrown crystals ▪ Intergrowthhappensduringformationofigneousrocks ▪ Commonexamplesare ▪ GraphicTextures ▪ Mostobviousandregularinbetweenquartzandfeldsparcrystals ▪ GranophyricTextures ▪ Intergrowthisirregular 5. INTERGRANULARTEXTURES ▪ Crystals formed at earlier stages may get so arranged that polygonal or trigonal spaces are left in between them ▪ Thespacesarefilledsubsequentlyduringrockformationbycrystallineorglassy masses of other minerals ▪ SometimestermedINTERSERTALifmaterialfillingthespaceisGLASSYinnature FORMS OF IGNEOUS ROCKS ▪ Factorsaffectingcoolingofigneousrocks ▪ Structuraldispositionofhostrock(countryrock) ▪ Viscosityofmagmaorlava ▪ Compositionofmagmaorlava ▪ Environmentinwhichinjectionofmagmaoreruptionoflavatakesplace Rate of Cooling/ Degree of Crystallization Holocrystallline ▪Allmineralcomponentsaredistinctlycrystallized ▪ Also termed as phaneric Holohyaline ▪Allcomponentsareveryfineinsizeandglassyornon-crystalline ▪ Also termed as aphinitic Merocrystalline ▪Intermediatetype ▪ Combination of crystallized and glassy character Shape as seen under the microscope Euhedral ▪ Perfectly shaped texture Subhedral ▪ Semi-perfect shaped texture ϕμ_αρδνασαχ / σκνλαζο 81 | Page Anhedral ▪Totallyirregularshapedtexture Granularity Coarse-grained ▪Averagegrainsizeisabove5mm ▪ Mineral components are easily identified by the naked eye Medium-grained ▪Averagegrainsizerangesfrom5mmto1mm ▪ magnifying lens necessary for identifying mineral components Fine-grained ▪Averagegrainsizeislessthan1mm ▪ Identification is only possible with microscope Fabric used to express relative grain size of different mineral components and degree of perfection in crystal form of individual minerals Panidiomorphic ▪Majorityofcomponentsarefullydevelopedshapes Hypidiomorphic ▪Containscrystalsofallshapecategory Allotriomorphic ▪Mostcrystalsareanhedralorirregular Other factors involved: DIFFUSION RATE - rate at which atoms or molecules can move through the liquid NUCLEATION RATE OF NEW CRYSTALS - rate at which enough of the chemical constituents can come together in one place without dissolving. GROWTH RATE OF CRYSTALS - the rate at which new constituents can arrive at the surface of the growing crystal; depends greatly on diffusion rate of molecules of concern SEDIMENTARY ROCKS areoftendepositedinlayers,andfrequentlycontainfossils. arealsocalledsecondaryrocks. formed through the deposition and solidification of sediment, especially sediment transported by water (rivers, lakes, and oceans), ice (glaciers), and wind. includes a wide variety of rocks formed by accumulation, compaction and consolidation of sediments. sedimentsmaybedefinedasparticlesproducedfromthedecayandweatheringof pre- existing rocks or may be derived from remains of dead sea or land animals in suitable environments accumulationandcompactionofthesesedimentscommonlytakesplaceunderwater or at least in the presence of water. FORMATION Theprocessofformationofsedimentaryrocksiseverprevailing. Thesedimentssoproducedaretransportedtothesettlingbasinssuchasseafloors where they are deposited, get compacted and consolidated and finally transformed into a cohesive solid mass. That is a sedimentary rock. ϕμ_αρδνασαχ / σκνλαζο 82 | Page  Some chemical processes especially evaporation and precipitation regularly operate on surface of water bodies containing dissolved salts and produce solids that settle down in those bodies. Sedimentaryrocksarebroadlygroupedintothreeclassesonthebasisoftheirmode of formation: Mechanically formed or Clastic Rocks; Organically formed Rocks and Chemically formed Rocks The last two groups are considered as a single class and named as Non-Clastic Rocks and Clastic (Mechanically Formed) Rocks Aseriesofwell-definedstepsareinvolvedintheformationofclasticrocks. 1. DECAYANDDISINTEGRATION Rocksexistingonthesurfaceoftheearthareexposedtodecayanddisintegration by the action of natural agencies like atmosphere, water and ice on them Theoriginalhardandcoherentrockbodiesaregraduallybrokendownintosmaller and still smaller fragments, grains and particles. Thedisintegrated,loosenedmaterialsoformedandaccumulatednearthesourceis called detritus. Hence, clastic rocks are often also called as detrital rocks 2. TRANSPORT OF SEDIMENTS Thedetritusproducedfromthedecayanddisintegrationofthepre-existingrocks forms the source of the sedimentary rocks but it has to be transported to a Suitable place for transformation again into a rock mass. Thewind,runningwaterandiceintheformofglaciersaretheverystrongand common agents of transport for carrying millions of tonnes of sediments and particles from one place to another including seas and oceans. Thewindstransportthesedimentsfromploughedfields,thedesertsanddrylandsin series of jumps (saltation) and in suspension modes. Theseloadsofsedimentsaredroppeddownwhereverinterceptedbyrains. Themightiestagentsoftransportofsedimentsare,ofcourse,streamsandrivers,all terminating into lakes or seas. Therunningwaterbodiestransportthesedimentloadasbed-load,suspended-load and. dissolved load, all dumped at the settling basins. Iceintheformofhugemovingbodiescalledglaciersalsobreakstherocksalong their bases and sides (in valley glaciers) and dumps the same at snow lines thereby making large volumes of the clastic load available for further transport by other agencies. It is easy to imagine that millions of tonnes of land mass as scratched by these surface agencies is transported to seas and oceans every year and deposited there. 3. GRADUALDEPOSITION The sediments as produced through weathering and erosion are transported to settling basins. These basins may be located in different environments such as on the continents, along the seashores or in deep-sea environments. As such sedimentary rocks formed in different environments will show different inherent characters. ϕμ_αρδνασαχ / σκνλαζο 83 | Page  Inthecontinentalenvironmentsmaybeincludedtheglacialdeposits,thefluvial deposits, the glacio-fluvial deposits and the eolian deposits, each type giving rise to a definite type of sediment accumulation. Inthemarinedeposits,somesedimentsmaybedroppedjustalongtheseashore,or at some shallow depth within the sea or miles away in the deep-sea environment. 4. DIAGENESIS The process of transformation of loose sediments deposited in the settlement basins to solid cohesive rock masses either under pressure or because of cementation is collectively known as diagenesis. Itmaybeachievedbyeitherofthetwomethods:weldingorcementation. WELDING (compaction) is the process of compaction of the sediments accumulated in lower layers of a basin due to the pressure exerted by the load of the overlying sediments. Thisresultsinsqueezingoutallormostofthewater.frominbetweenthesediments, thus bringing them closer and closer and consolidating them virtually in a solid rock mass. Infactthedegreeofpackingofsedimentsinasedimentaryrockisbroadlydirectly proportional to the load of the overlying sediments. CEMENTATION is the process by which loose grains or sediments in a settlement basin get held together by a binding material. Thebindingmaterialmaybederivedfromwithintheaccumulatedparticlesorthe fluids that percolate through them and also evaporate or precipitate around those particles thus binding them in a rock like mass. CLASSIFICATION OF SEDIMENTARY ROCKS 1. CLASTICROCK(alsocalledCHEMICALLY-FORMEDROCKS) ϕμ_αρδνασαχ / σκνλαζο 84 | Page  “Clastic”comesfromtheGreekwordfor“broken” referstofragmentsofrockandmineralscreatedbyweatheringanderosion. Classifiedbyparticlesize 2. NON-CLASTIC(oralsocalledORGANICALLY-FORMEDROCKS) Theseextensivewaterbodiessustainagreatvarietyofanimalandplantlife. Thehardpartsofmanyseaorganismsareconstitutedchieflyofcalciumand/or magnesium, carbonates. Deathanddecayoftheseorganismswithinthewaterbodiesgraduallyresultsinto huge accumulations of carbonate materials, which get compacted and consolidated in the same manner as the normal sediments. Limestonesarethebestexamples. METAMORPHOUS PETROLOGY Metamorphic rocks arise from transformation of existing rock types in a process called metamorphism protoliths may be sedimentary rock, igneous rock or another older metamorphic rock. ϕμ_αρδνασαχ / σκνλαζο 85 | Page Metamorphism The change of mineral or geologic texture in pre-existing rocks occurs primarily due to heat, pressure and the introduction of chemically active fluids changes at or just beneath Earth’s surface due to weathering and/or diagenesis are not classified as metamorphism typically occurs between diagenesis 200oC and melting 850oC. Metamorphic mineral form only at the high temperatures and pressures associated with the process of metamorphism known as index minerals, include laumontite, lawsonite, glaucophane, paragonite, pyrophyllite, sillimanite, kyanite, staurolite, andalusite and some garnet. Migmatite A rock at the frontier between igneous and metamorphic rocks also be known as diatexite. Metasomatism chemical alteration of a rock by hydrothermal and other fluids is open system behavior which is different from classical metamorphism which is the in-situ mineralogical change of a rock without appreciable change in the chemistry of the rock **Note: Metasomatism and metamorphism nearly always occur together Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to: highheat, highpressure, hotmineral-richfluidsor,morecommonly,somecombinationofthesefactors. Conditions like these are found deep within the Earth or where tectonic plates meet. PROCESS OF METAMORPHISM metamorphismdoesnotmelttherocks,butinsteadtransformsthemintodenser, more compact rocks Newmineralsarecreatedeitherbyrearrangementofmineralcomponentsorby reactions with fluids that enter the rocks Pressureortemperaturecanevenchangepreviouslymetamorphosedrocksinto new types Metamorphicrocksareoftensquished,smearedout,andfolded Despiteuncomfortableconditions,metamorphicrocksdonotgethotenoughto melt, or they would become igneous rocks. Metamorphism occurs in the solid state and doesn’t include: Weathering Diagenesis Melting Metamorphic change is slow and in the solid state. ϕμ_αρδνασαχ / σκνλαζο 86 | Page METAMORPHISM PROCESSES that work simultaneously: 1. RECRYSTALLIZATION–mineralschangesize/shape 2. PHASE CHANGE – new minerals from with same chemical formula but different crystal structure (Example: andalusite to kyanite) 3. NEOCRYSTALLIZATION – new minerals with changes in temperature and pressure. – Initial minerals become unstable and change to new minerals. Originalprotolitharedigestedinreactions. Elementsrestructuretoformnewminerals. In this way, shale can transform into garnet mica schist. 4. PRESSURE SOLUTION. – Mineral grains partially dissolve. – Dissolution requires small amounts of water. – Minerals dissolve where their surfaces press together. – Ions from the dissolution migrate in the water film. ϕμ_αρδνασαχ / σκνλαζο 87 | Page  5. PLASTIC DEFORMATION – mineral grains soften and deform. Requireselevatedtemperatures. Rockissqueezedorsheared. Mineralsactlikeplastic,changingshapewithoutbreaking. GROUPS OF MINERALS FORMED 1. STRESSMINERALS Theminerals,whichareproducedinthemetamorphicrockschieflyunder differential stress factor. Theyarecharacterisedbyflaky,platy,lamellar,flattenedandElongatedforms. 2. ANTI-STRESS MINERALS ϕμ_αρδνασαχ / σκνλαζο 88 | Page  Thesearemetamorphicmineralsproducedprimarilyundertheinfluenceof temperature factor. Suchmineralsaregenerallyofaregularequidimensionaloutline. Examples: sillimanite,olivine,cordieriteandmanypyroxenes MINERALOGICAL COMPOSITION Metamorphic rocks exhibit a great variation in their mineralogical composition that depends in most cases on (i) the composition of the parent rock; (ii) the type and degree of metamorphism undergone by the rock. TEXTURES OF METAMORPHIC ROCKS 1. CRYSTALLOBLASTIC Textures which include all those textures that have been newly imposed upon the rock during the process of metamorphism and are, therefore, essentially the product of metamorphism. 2. PALIMPSEST (RELICT) Texturesthatincludetextureswhichwerepresentintheparentrockandhavebeen retained by the rock despite metamorphic changes in other aspects. Amongthecrystalloblastictextures,PorphyroblasticandGranoblastictypesare most common. outlines) of stronger minerals. Inthegranoblastictexture,therockismadeofequidimensionalrecrystallized minerals without there being any fine grained ground mass. Palimpsesttexturesaresimilarinessentialdetailsasintheparentrockwithlittleorno modifications taking place during metamorphism. Thesearedescribedbyusingthetermblastoasaprefixtothenameoftheoriginal texture retained by the rock. CLASSIFICATION OF METAMORPHIC ROCKS Metamorphic rocks have been variously classified on the basis of: 1. textureandstructure, 2. degreeofmetamorphism, 3. mineralogicalcompositionand 4. modeoforigin 1. FOLIATEDROCKS Allmetamorphicrocksshowingdevelopmentofconspicuousparallelismintheir mineralogical and structural constitution falling under the general term foliation are grouped together as foliated rocks. ϕμ_αρδνασαχ / σκνλαζο 89 | Page  Theparallelismindicatingfeaturesincludeslatycleavage,schistosityandgneissose structures Typicalrocksincludedinthisgroupareslates,phyllites,schistsandgneissesofgreat variety. 2. NON-FOLIATED ROCKS Includedinthisgroupareallthosemetamorphicrockscharacterisedwithtotalor nearly total absence of foliation or parallelism of mineralogical constituents. Typicalexamplesofnon-foliatedrocksarequartzites,hornfels,marbles,amphibolites and soapstone etc. EXPLAIN IMPORTANT IGNEOUS ROCKS 1. PLUTON adeep-seatedintrusionof igneous rock,a body that made its way into pre-existing rocks in a melted form (magma) several kilometers underground in the Earth's crust and then solidified magma cooled and crystallized very slowly, allowing the mineral grains to grow large and tightly interlocked — typical of plutonic rocks. 2. BATHOLITHS a giant mass of intrusive igneous rock that forms when magma collects and cools deep in the earth’s crust without being exposed to the surface usuallylargerthan40squaremiles maincompositioniscoarsegrainedgranite Mostly formed inside mountain folds that have undergone faulting as this creates spaces that the magma can intrude into and form a new structure after cooling 3. DIKES a body of rock, either sedimentary or igneous, that cuts across the layers of its surroundings ϕμ_αρδνασαχ / σκνλαζο 90 | Page  form in pre-existing fractures, meaning that dikes are always younger than the body of rock that they have intruded into. 4. SILLS atabularsheetintrusionthathasintruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or even along the direction of foliation in metamorphic rock. Thetermissynonymouswithconcordant intrusive sheet. 5. LACOLITHS aremushroom-shapedbodieswithaflatfloor and a domed roof. Thus, they appear to have begun forming in the same way as sills; however, as magma continued to intrude, it pushed up the overlying layers rather than continuing to spread out laterally. 6. VOLCANIC NECKS alsocalledavolcanicplugorlavaneck is a volcanic landform created when lava hardens within a vent on an active volcano ϕμ_αρδνασαχ / σκνλαζο 91 | Page  When forming, a plug can cause an extreme build-up of pressure if volatile-charged magma is trapped beneath it, and this can sometimes lead to an explosive eruption If a plug is preserved, erosion may remove the surrounding rock while the erosion-resistant plug remains, producing a distinctive landform. Most Common Igneous Rocks 2. GRANITE acommontypeofintrusive(plutonic) rocks. Itislightcolorwithpinktogreycolor. This rock mainly consists of quartz, feldspar and mica. used as the most important building stone for the decorative, monumental, and architectural purposes because of its light color. 3. GABBRO Itiscoarsegrained,intrusivemaficigneousrock which is chemically equivalent to basalt. Itisdarkincolorwithgreytoblack. It is used as a road material and concrete aggregate. Itisalsousedinkitchenandtheircountertops. Also widely used as graveyard headstone. 4 BASALT. Basalt is common extrusive (volcanic) rock formed by the rapid cooling of lava. It is usually grey to black in color. It has fine-grained mineral texture. It is used in construction (as building blocks or in groundwork) It is also used in construction of bridges, making cobblestones, and making statues. ϕμ_αρδνασαχ / σκνλαζο 92 | Page