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ELS REVIEWERTheories Behind the Origin of the Universe 1. The Big Bang Theory – The most accepted theory about the origin of the universe; postulates that 13 billion years ago, the universe expanded from a tiny, dense and hot mass to its present size and much cooler state.  Georges Lemaitre – consi...

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ELS REVIEWER Theories Behind the Origin of the Universe 1. The Big Bang Theory – The most accepted theory about the origin of the universe; postulates that 13.8 billion years ago, the universe expanded from a tiny, dense and hot mass to its present size and much cooler state.  Georges Lemaitre – considered as the first proponent of the Big Bang Theory in 1927.  Edwin Hubble – confirmed Lemaitre’s theory that the universe is expanding; He also demonstrated that the universe was much larger than previously thought. Evidences  Redshift – the light spectrum in the universe is shifting to the red color.  Relative abundance – the prediction of the Big Bang with regard to the number of light elements in space is correlated with the evidences (74% Hydrogen, 24% Helium, 2% other elements)  Cosmic microwave background – there are evidences of microwaves which are the energy left after recombination of elements. 2. Pulsating/Oscillating Universe Theory – discusses that the universe is expanding and will contract once all the energy after the Big Bang is used up; This theory, proposed by Richard Tolman (1934), can be described as the combination of the Big Bang and the Big Crunch.  The Big Crunch occurs when the universe expands and eventually reverse, then collapses causing a singularity or the formation of another Big Bang.  The Oscillating Universe Theory suggests that once the universe reverses and attains the point of singularity, another universe will be born. 3. Steady State Theory – proposed by Fred Hoyle, Thomas Gold, Herman Bondi in 1948; it suggests that the universe has always been there and will always be present.  It also conveys that the universe always looks the same in any time or space but continuously expands while simultaneously creating matter, maintaining the density of the universe, hence, the name Steady State.

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Solar System - is located in the Milky Way galaxy a huge disc and spiral-shaped aggregation of about at least 100 billion stars and other bodies; Its spiral arms rotate around a globular cluster or bulge of many, many stars, at the center of which lies a supermassive blackhole; The solar system revolves around the galactic center once in about 240 million years. The Milky Way is part of the so-called Local Group of galaxies, which in turn is part of the Virgo supercluster of galaxies. Much of the mass of the Solar System is concentrated at the center (Sun) while angular momentum is held by the outer planets. Orbits of the planets elliptical and are on the same plane. All planets revolve around the sun. The periods of revolution of the planets increase with increasing distance from the Sun; the innermost planet moves fastest, the outermost, the slowest. All planets are located at regular intervals from the Sun.

Theories of Solar System 1. Encounter Hypothesis - In this scenario, a rogue star passes close to the Sun about 5 billion years ago. 2. Nebular Hypothesis - the whole Solar System starts as a large cloud of gas that contracts under self-gravity. 3. Protoplanet Hypothesis - It incorporates many of the components of the nebular hypothesis, but adds some new aspects from modern knowledge of fluids and states of matter. 4. Condensation Theory – Once the solar nebula has formed and begun to cool, dust acts as condensation nuclei around which matter starts to gather. Uniqueness of Earth, Being the only planet in the Solar System With Properties to Support Life  Atmosphere, Temperature, Water, Sunlight and Photosynthesis, The right moon, The right sun, The right core, The right neighbors 

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Earth is the third planet from the sun and the only planet in the solar system that can sustain life. Pictures taken from space describe Earth as “The Blue Marble” since what we mostly see is the vast oceans of Earth that has a far larger area than the land. 1. Hydrosphere – the water portion of Earth Atmosphere – the gaseous envelope of the Earth.

Geosphere / Lithosphere – the solid component of the Earth. 4. Biosphere – the living component of Earth. Layers of Atmosphere – Exosphere, Thermosphere, Mesosphere, Stratosphere, Troposphere

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Structure of the Earth  Crust – is the layer that you live on so it is the most widely studied and understood. It is made up of the lightest matter.  Mantle – the largest layer of the Earth. It is made up of hot, dense rock. The rock in the mantle flows like asphalt because of the temperature differences found in the mantle.  Outer Core – is liquid; it is made up of iron and is very dense.  Inner Core – has temperatures and pressures so great that the metals are squeezed together and are not able to move. It is solid.  Lithosphere – it is the solid, outerpart of the Earth. It includes the brittle upper portion of the mantle and crust, the outermost layers of Earth’s structure.  Astenosphere – it is a layer of solid rock that has so much pressure at heat the rocks can flow like a liquid.

Where do rocks melt? Subduction zones, Felsic and Intermediate, Mantle plumes (hot spots)

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Igneous Rock – most abundant; primary rocks; soure is magma or lava Sedimentary Rock – thin veener in Oceanic and Continental Crusts; secondary rocks. Metamorphic Rock – proportion is similar to that of Igneous Rock; change of forms of Igneous and Sedimentary due to Temperature, Pressure and Chemical Fluids.

Lava – molten rock that erupts onto the Earth’s surface through a volcano or crack (fissure)

How are rocks melted? Heating, Depressurization, Increased water content, Increased silica content

Cooling Rates of Magma  Quick cooling – fine grains  Slow cooling – coarse grains  

Different magmas have different viscosities. Viscosity is the property of a substance to internally resist flow. The higher the viscosity, the more resistance to flow.

Igneous Textures  Glassy – instantaneous cooling. Example: Obsidian  Aphanitic – fine grain size; result of quick cooling. Example: Basalt, Rhyolite, Andesite  Phaneritic – coarse grain size; visible grains; result of slow cooling. Example: Granite, Diorite, Gabbro  Porphyritic – mixture of grain sizes caused by mixed cooling history; slow cooling first, followed by a period of somewhat faster cooling.  Vesicular – contains tiny holes called vesicles which formed due to gas bubbles in the lava or magma. Very porous. May resemble a sponge. Commonly low density; may float on water.  Pyroclastic or Fragmental – pieces of rock and ash come out of a volcano and get welded together by heat.  Tuff – made of volcanic ash  Volcanic breccia - contains fragments of fine-grained igneous rocks that are larger than ash 

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Magma – molten rock below the Earth’s surface

Volcanic Rocks (Extrusive Rocks) – lava or magma flows; pyroclastic flows; form at the earth's surface as lava cools. Intermediate Rocks (Hypabyssal Rocks) Plutonic Rocks ( Intrusive Rocks) – dykes, sills, batholiths, laccoliths, etc; form deep underground where magma cools slowly.

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Felsic – Granite; Poor in Iron, Magnesium and Calcium but Rich in Silica

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Mafic – Hot, Non-viscous, Dry;

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Mafic Rocks - Usually Extrusive, Fine-grained, Mafic (Basalt) rock forms oceanic crust, Shield Volcanoes and Basalt Floods. If Intrusive, coursegrained mafic rocks are formed Gabbro. If intrusive, Dikes and Sills more common

Intrusive Extrusive

Felsic Granite Rhyolite

Intermediate Diorite Andesite

Some examples of chemical sedimentary rocks include;

Mafic Gabbro Basalt

Bowen’s Reaction Series 1. Discontinuous reaction series, from olivine, pyroxene, hornblende, biotite, feldspar, quartz. 2. Continuous reaction series, from Ca plagioclase to Na plagioclase. 

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Silica Rich (Felsic) – known as acidic magma; more viscous, do not spreads and piles up at one place (trap gas easily). Silica Poor (Mafic) – known as basic magma; less viscous, moves faster and occupies larger area (release gas easily). Plutons – igneous rocks cooled at depth. Dikes – small shallow intrusions that show a discordant relationship to the rocks in which they intrude. Sills – are also small shallow intrusions that show a concordant relationship with the rocks that they intrude. Laccoliths – are somewhat large intrusions that result in uplift and folding of the pre-existing rocks above the intrusion. Batholiths – are very large intrusive bodies, usually so large that there bottoms are rarely exposed. Sometimes they are composed of several smaller intrusions.

Sedimentary Rocks – usually originate in water environments, either oceans, lakes, or river beds. 1. Clastic/Detrital Sedimentary Rocks – mechanical rock weathering by products are transported to new location, cement together. 2. Chemical Sedimentary Rocks – soluble material, dissolved by chemical weathering, precipitates by organic or inorganic processes. 3. Biochemical/Organic Sedimentary Rocks – these rocks form as a result of once living organisms accumulating to form solid rock. Particle Name Sediment Rock Name Name Boulder, Gravel Conglomerate, Pebble Breccia Sand Sand Sandstone Silt/Clay Mud Siltstone/Shale

Limestone (Calcite) (form by precipitation) Rock Gypsum - (form by precipitation and evaporation) Rock salt (Halite) – (from by evaporation) Coquina - (form by biochemical processes) 

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Metamorphic Rock - The term “metamorphic” means “to change form.” Any rock can become a metamorphic rock. If rocks are buried deep in the Earth at high temperatures and pressures, they form new minerals and textures all without melting. If melting occurs, magma is formed, starting the rock cycle all over again. Metamorphic Rocks – are formed when other rocks are exposed to high heat and pressure.  Foliated – the minerals in these rocks have been flattened and pushed into parallel layers. Examples: shale, slate, gneiss  Nonfoliated – do not display layers. Examples: quartzite, marble, anthracite coal Sediments – are loose materials such as rock fragments, mineral grains, and bits of shell that have been moved by wind, water, ice, or gravity. Sedimentary Rock – forms when sediments are pressed and cemented together, or when minerals form from solutions.

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Clastic – Conglomerate, Sandstone, Shale Organic – Coal, Fossiliferous Limestone Chemical – Limestone, Salt Sedimentary Rocks – are made from already existing rocks that are weathered and eroded. It forms when sediments are pressed and cemented together, or when minerals form from solutions. Detrital – made from broken fragments of other rocks. These are created by weathering and then moved by erosion. If sediments have small pieces then compaction occurs. If sediments have large pieces then cementation occurs. Chemical – formed from dissolved minerals come out of solutions. Example: Halite, Limestone Organic – made of the remains of once living things. Example: chalk, coal

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Mineral – natural, inorganic, solid, unique chemical composition, crystalline shape Physical Properties of Mineral – Color/Appearance, Luster, Streak, Hardness, Cleavage/Fracture,  Luster – refers to the way a mineral reflects light from its surface.  Streak – the color of the powdered form of the mineral.  Hardness – how easily a mineral scratches materials. Mohs Scale of Hardness  Cleavage – minerals break along smooth, flat surfaces.  Fracture – minerals that break at random with rough or jagged edges.

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Special Properties of Some Minerals – Fluorenscence, Chemical Reaction, Optical Properties, Taste, Magnetism, Radioactivity

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Exogenic Process – originate externally about the Earth. The source of energy of this processes is not the Earth itself but outside of the Earth. Sun is the main source of energy for exogenous processes. The Sun’s energy is carried by wind, water, etc. Living organisms and gravity are also another sources of energy. Weathering – the breakdown or disintegration of rocks and their minerals into smaller fragments and/or decay and transformation into other substances. Physical Weathering – is caused by physical changes such as changes in temperature, freezing ang thawing, and the effects of wind, rain and waves. Temperature changes – when a rock gets hot it expands a little, and when a rock gets cold it contracts a little. Wind, rain and waves – the wind can blow tiny grains of sand against a rock. These wear the rock away and weather it. Rain and waves can also wear away rock over long periods of time.

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Freeze-thaw – water expands slightly when it freezes into ice. This is why water pipes sometimes burst in the winter. Chemical Weathering – the weathering of rocks by chemicals is called chemical weathering. Rainwater is naturally slightly acidic because carbon dioxide from the air dissolves in it. Minerals in rocks may react with the rainwater, causing the rock to be weathered. Acid rain – when fossil fuels such as coal, oil and natural gas are burned, carbon dioxide and sulfur dioxide escape into the air. These dissolve in the water in the clouds and make the rainwater more acidic than normal. Dissolution – dissociation of molecules into ions; common example includes dissolution of calcite and salt. Oxidation – reaction between minerals and oxygen dissolved in water. Hydrolysis – change in the composition of minerals when they react with water. Biological Weathering – animals and plants can wear away rocks. Erosion – the movement of the broken pieces away from the site of weathering. Factors affecting erosion – running water, strong wind, gravity Transport – rivers and streams can move pieces of rock. Deposition – settling down of the transported materials. Mass wasting – refers to the process that bring about the transport of materials along a slope due mainly to the action of the gravity. Types of Mass Wasting – landslide, avalanche, rock fall, creep Landslide – mass-wasting events where large amounts of weathered rock material slide down a hillslope or mountain side primarily by gravity related erosion. Avalanche – an event that occurs when a cohesive slab of snow lying upon a weaker layer of snow fractures and slides down a steep slope. Rock fall – occur when rocks become dislodged. As a result the rocks fall, roll, or bounce downhill. Creep – the slowest mass-wasting process and involves a very gradual downhill movement of soil, bedrock, and weathered rock fragments. Effects of Exogenous Processes – levelling of land, weathering of rocks, formation of soil, erosion of rock fragments and/or soil, deposition of fragments and/or soil, formation of sedimentary rocks. Endogenic Process – originates from within the Earth itself. The source of energy arises internally from the Earth itself. It shapes the planet’s surface from within. Sources of Internal Heat – primordial heat, radiogenic heat Primordial Heat – left over heat from the formation of the planet earth about 4.5 billion years ago.

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Radiogenic Heat – radioactive decay of naturally radioactive elements like U-238 , U-235, Th-232, K-40 in the Earths lithosphere. Magma formation – When volatiles mix with hot, dry rock, the volatile decreases the rock’s melting point and they help break the chemical bonds in the rock to allow melting. A rising magma from the mantle brings heat with it that can melt the surrounding rocks at the shallower depths. Types of endogenous processes – folding, faulting, volcanism Effects of the flow of internal heat to the surface of the Earth – formation of magma, mantle convection, seafloor spreading, continental drift. Specific sites of rock melting – hotspot, subduction zones, below mid-ocean ridges Hotspot – at the hotspot, the base of the lithosphere is heated by the rising hot mantle rocks. This site is also called mantle plumes. Mantle convection – causes seafloor spreading which results in continental drift. Folding – process that causes rocks to bend or curve when forces are applied on their opposite ends. Faulting – process causing fracture, breaks, or cracks in rocks or rock layers due to shear forces applied that overcome the forces that hold them together. Normal fault – the rocks on either side of the fault line is divided into footwall and hanging wall. Strike-slip fault – the rocks on the either side of the fault line move horizontally in opposite direction past each other. Reverse fault – the rocks moves in reverse direction compared to the normal fault. Oblique-slip fault – rocks in this fault exhibited both horizontal and vertical movements. Faults – potential source of earthquake and can cause mountains to form. Earthquake Focus – where the movement begins Epicenter – the point directly above the focus Shallow earthquake – if the focus is 60km deep Intermediate earthquake – if the focus is 60-300 km deep Deep earthquake – if the focus is beyond 300km Volcanism – volcano is one of the means of internal heat of the Earth gets to the surface of the planet. Usually occur at plate boundaries.

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Crustal Deformation and Mountain Building – the process of forming a mountain not only uplifts the surface of the Earth, it causes rocks to undergo Deformation. Deformation – the process by which rocks are deformed in response to squeezing, stretching, shearing, etc.

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Deformation produces a variety of geologic structures including Joints, Faults, Folds, Foliation Except for volcanoes, mountains do not typically occur in isolation; they occur in linear ranges called Mountain Belts, or Orogenic Belts. Orogeny – a mountain building event; lasts 10 million years. In an undeformed sequence, strata occurs in horizontal layers, just like it was deposited. No metamorphic rocks, no foliation, no large faults, maybe some joints. Grains are round, just like when they were deposited, clay minerals are horizontally-aligned from compaction. In a deformed sequence, rocks are folded, and possibly metamorphosed. Faults with large offsets may be present, juxtaposing different rocks side by side. Rocks may be highly folded and squashed grains may create strong foliations. Brittle Deformation (lithosphere): Low temp & pressure (shallow depth)/high strain rates, Forms faults, joints, etc. Ductile Deformation (asthenosphere): High temps & pressures (deep depth)/low strain rates, Forms folds and foliations. Strain: A change in size and/or shape due to the application of stress Stress: A force exerted over some area that causes rocks to undergo strain Forces that causes the Earth’s crust to deformation – tension, compression, shear, confining stress Tension – is stress that stretches and pulls a body of rock apart. It occurs at or near divergent boundaries. Compression – is the type of stress that squeezes and shortens a body of rock. It occurs at or near convergent boundaries. It can cause folds or fracture. Shear – stress distorts a body of rock by pushing parts of the rock in opposite directions. It occurs at transform boundaries. Confining stress – is a type of stress that comes from all direction making the crust to eventually shrink. These type of stress can result to the formation of sinkholes. Types of Plate Boundaries – convergent, divergent, transform Convergent Plate Boundary – two plates collide with each other. Divergent Plate Boundary – two plates move away from each other. Transform Plate Boundary ...