Earth Science Reviewer PDF

EARTH SCIENCE REVIEWER Module 1.1 Universe is a vast expanse of space which contains all of everything in existence. The universe contains all of the galaxies, stars, and planets. The exact size of the universe is unknown. Scientists believe the universe is still expanding outwar...

EARTH SCIENCE REVIEWER Module 1.1 Universe is a vast expanse of space which contains all of everything in existence. The universe contains all of the galaxies, stars, and planets. The exact size of the universe is unknown. Scientists believe the universe is still expanding outward. At least 13.8 billion years old Solar System is the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly. is thought to have formed 4.6 x 109 years ago from a vast, rotating cloud of gas and dust known as the solar nebula As the solar nebula rotated, its gravity began to attract gas and dust towards the center, eventually forming our Sun. At least 4.6 billion years old ORIGIN OF THE UNIVERSE Theories Behind the Origin of the Universe RELIGIOUS THEORY Hebrew Bible - God separated light from darkness, created sky, land, sea, moon, stars, and every living creature. Hindu Text “Rig Veda” - Universe is an oscillating which a cosmic egg or Brahmanda containing the whole universe. Primordial Universe (Greeks) - the original state of the cosmos was a primordial mixture of all of its ingredients which existed in infinitesimally small fragments of themselves. Atomic Universe - Greek Philosophers Leocippus and Democritus believed that the universe is composed of tiny, inseparable, and indestructible atoms. SCIENTIFIC THEORY Steady State Theory - The Universe has always been the same since the beginning and it remain that way forever  Big Bang Theory - states that the earliest state of the universe was an extremely hot and dense one and that the universe subsequently expanded and cooled - claim that all of the galaxies, stars, and planets still retain the explosive motion of the moment of creation and are moving away from each other at great speed. Oscillating Universe Theory - George Gamow - Expansion will stop, return to its original form then Big Bang will occur Cosmic inflation Theory - Proposed by Alan Guth, Andrei Line, Paul Stein Hart, Andy Albrecht - After Bigbang, the universe expanded very, very rapidly - much faster than the speed of light. A fraction of second laer, the expansion slowed. The universe continue to expand but in slower rate. Multiverse - The universe is just one of the many bubbles that grew as a part of multiverse - Concept of many world THE SOLAR SYSTEM Geocentric - Earth centered - The Greek astronomer Ptolemy used measurements of the sky to create his geocentric model. - This had the earth at the center and all the planets and the sun orbiting around it. Heliocentric - Sun Centered - This theory was first proposed by Nicolaus Copernicus. Copernicus was a Polish astronomer - He first published the heliocentric system in his book: De revolutionibus orbium coelestium, "On the revolutions of the heavenly bodies," which appeared in 1543. THE EIGHT PLANETS The inner four planets closest to the sun — Mercury, Venus, Earth and Mars — are often called the "terrestrial planets" because their surfaces are rocky. Mercury is the smallest of the terrestrial planets. It has an iron core that accounts for about 3/4 of its diameter. Because it is so close to the Sun, it is very difficult to see Mercury. Venus is the one most similar to Earth. In fact, Venus is often called Earth's “sister” planet. Earth and Venus are similar in size. The two planets are very close to each other as they orbit the Sun Venus is the most visible planet in the night sky. Both planets are relatively young, judging from the lack of craters on their surfaces. Earth only planet known where life exists. While other planets may have small amounts of ice or steam, the Earth is 2/3 water. Earth has perfect conditions for a breathable atmosphere. Earth is the largest of the terrestrial planets and the fifth largest in the solar system. It is believed to be about 4.5 billion years old, which makes it very young compared to other celestial bodies Mars It may be the reddish color of Mars, or the fact that it can often be easily seen in the night sky, that has caused people to wonder about this close neighbor of ours The four large outer worlds — Jupiter, Saturn, Uranus and Neptune — are sometimes called the Jovian or "Jupiter-like" planets because of their enormous size relative to the terrestrial planets. They're also mostly made of gases like hydrogen, helium and ammonia rather than of rocky surfaces, although astronomers believe some or all of them may have solid cores. Jupiter is first among the planets in terms of size and mass. Its diameter is 11 times bigger than Earth, and its mass is 2.5 times greater than all the other planets combined. The “Great Red Spot” on Jupiter is actually a raging storm. Saturn is the second largest planet. It is the farthest planet from the Earth that can be seen without a telescope. it appears flat at the poles because its great rotational speed makes the middle of the planet bulge. Uranus is the first planet so far away from the Earth that it can only be seen with the use of a telescope. Uranus is so far from the Sun that it takes 84 years to complete an orbit of the Sun. It is the only planet that spins on its side, so each pole is tilted away from the Sun for half its orbit. That means each night and day lasts an amazing 42 years. Neptune was named after the Roman god of the sea because it is so far out in the deep “sea” of space. The name also fits because Neptune appears to be a beautiful bright blue because of the methane clouds that surround it. It is the most distant planet from the Sun. It takes a very long time—165 years— to orbit the Sun. Neptune has made only one trip around the Sun since it was discovered. THE EARTH AND ITS SUBSYSTEMS  System – A set of interconnected components that are interacting to form a unified whole. ATMOSPHERE The atmosphere is the layer of gases that surround the Earth. In comparison to the size of the Earth, it is a thin layer, composed primarily of nitrogen and oxygen with small amounts of carbon dioxide and other gases. The atmosphere is important for a number of reasons – it protects the Earth from incoming solar rays, it circulates the gases that plants and animals need to survive and it is responsible for our weather. BIOSPHERE The biosphere consists of all the living organisms on Earth. Their habitats extend from the upper areas of the atmosphere, to deep in the ground, to the bottom of the ocean – any place that life can exist. GEOSPHERE The geosphere is the physical Earth – the rock, magma and soil. The geosphere extends from the centre of the Earth (the core, mantle and crust) to the dust in the atmosphere and even includes the sediments found in the oceans. HYDROSPHERE The hydrosphere is all the water held on the Earth – water molecules in the air, icebergs and glaciers, groundwater, lakes, rivers and oceans. Module 1.2 EARTH AS A SYSTEM System – entity that consists of interrelated parts or components. Earth system – relies on the interactions among a vast combination of factors that enable it to support life. Variables – individual components of a system that change by interacting with one another as parts of a functioning unit. Subsystem – functioning units of a major system that demonstrate strong internal connections. EARTH’S MAJOR SUBSYSTEMS 1. Atmosphere – gaseous blanket of air that envelops, shields, and insulates Earth. Layers of the Atmosphere A. Troposphere -Layer nearest the earth. - It contains 75% of the gases of the atmosphere as well as dust and water vapor. - Zone where weather occurs. - Temperature decreases with increasing height in the troposphere.  Tropopause - Boundary between the troposphere and stratosphere. - Acts as a ceiling to the weather zone. - Contains stormy winds called the jet streams. B. Stratosphere - Contains a layer of ozone. - Ozone keeps most of the ultraviolet radiation from the sun from reaching the earth’s atmosphere. - Temperature increases with increasing height in the stratosphere. Stratopause - Temperature is at 0 degrees Celsius. - Boundary between the stratosphere and mesosphere. C. Mesosphere - Coldest zone of the atmosphere. - Here, the temperature is midway between that in the troposphere and in the stratosphere. Mesopause - Temperature decreases up to -80 degrees Celsius. - Boundary between the mesosphere and thermosphere. D. Thermosphere - Due to the absorption of solar energy in this layer, the temperature increases rapidly with altitude. Ionosphere - Layer of electrically charged particles. - Contains the ions that are formed due to the bombardment of the atmospheric particles by the energy from the sun. - These ions are useful for communications because they reflect radio waves. Auroras - Ions glow in different colors due to solar flares. - Brightest at the poles due to the deflection of the particles by the earth’s magnetic field. - Cause disturbances in radio, television, and telephone transmissions. E. Exosphere - Outermost part of the atmosphere. - First-hand protection for incoming meteoroids and space debris. 2. Hydrosphere – includes the waters of the Earth and is mainly responsible for the hydrologic cycle. 3. Lithosphere – makes up the solid Earth (e.g., landforms, rocks, soils, and minerals). 4. Biosphere – composed of all living things: people, animals, and plants Environment - Can be defined as out surroundings: including all physical, social, and cultural aspects of the world, that affects the growth, the state of health, and the way of living of organisms. Ecosystem - Community of organisms and the relationships of those organisms to each other and to their environment. Ecology - Study of relationships between organisms and their environments LAYERS OF THE EARTH 1. Core - Earth’s innermost section. - Contains one-third of the Earth’s mass and has a radius of about 3360 kilometers. - It is under enormous pressure and is composed primarily of iron and nickel. - Temperature ranges of 4800 degrees Celsius (on the outer core) to 6900 degrees Celsius (on the inner core) Inner core - Has a radius of about 960 kilometers. - It is a solid with a very high material density. Outer core - Forms a 2400-kilometer-thick band around the inner core. - Is molten and it consists of molten rock matter. Principles about the core 1) Melting temperature of rock matter increases with pressure, and pressure increases with depth beneath the earth’s surface. 2) Rock existing under greater pressure needs to achieve a higher temperature to melt than rock at a lower pressure does. 3) Inner core – actual temperature is less than pressure-altered temperature, thus, remaining solid. 4) Outer core – actual temperature is greater than pressure-altered temperature, thus, becoming molten. 7 2. Mantle - Largest of Earth’s interior zones. - Approximately 2885 kilometers thick and represent nearly two-thirds of the Earth’s mass. - Composed of solid rock matter. - Consists of silicate rocks that also contain significant amounts of iron and magnesium. Lithosphere - Brittle, outer shell of Earth including the crust and the rigid, uppermost mantle layer. - An elastic solid. - Elastic solids are rigid and brittle. They do not flow, but instead withstand a certain amount of applied stress with little deformation until a threshold limit of stress is reached. - At the threshold value, elastic solids fail by fracturing, crumpling or warping. Asthenosphere - Thick layer of the upper mantle. - A plastic solid. - Responds to stress by deforming and flowing slowly rather than by fracturing. - The energy for tectonic forces comes from movement within the plastic asthenosphere. - Movement in the asthenosphere, in turn, is produced by thermal convection currents in the rest of the mantle that are driven by heat from decaying radioactive materials in the Earth’s interior. Mohorovicic discontinuity (Moho) - Interface between the mantle and the overlying crust. - Does not lie at a constant depth but generally mirrors the surface topography, being thickest at continental plates and thinnest at the ocean floors. 3. Crust - Earth’s solid exterior. - Composed of a great variety of rock types that respond in diverse ways and at varying rates to surface processes. - Represents only about 1 % of the Earth’s planetary mass. - Is relatively cold compared with the mantle and behaves in a more rigid and brittle manner. - Responds to stress by fracturing, crumpling, or warping. Oceanic crust - Composed of basalt (a heavy, dark-colored, iron-rich rock that is also high in silicon and magnesium) - Only a few kilometers thick and form the vast, deep ocean floors. Continental crust - Comprises the major landmasses on Earth that are exposed to the atmosphere. - Considerably thicker than oceanic crust. - Contains more light-colored rocks than oceanic crust does and can be regarded as granitic in composition. Module 2 MINERALS Mineral - naturally occurring, inorganic solid with orderly crystalline structure and a definite chemical composition. These are the basic building blocks of rocks. naturally occurring inorganic solid definite chemical composition ordered internal structure MINERAL PROPERTIES 1. Luster - it is the quality and intensity of reflected light exhibited by the mineral. 2. Hardness - it is a measure of the resistance of a mineral (not specifically surface) to abrasion. 3. Color and Streak - Color maybe a unique identifying property of certain minerals. There are also lots of minerals that share similar or the same color/s. In addition, some minerals can exhibit a range of colors. - Streak on the other hand is the color of a mineral in powdered form. Note that the color of a mineral could be different from the streak. 4. Crystal Form - The external shape of a mineral crystal (or its crystal form) is determined largely by its internal atomic structure, which means that this property can be highly diagnostic. 5. Cleavage - It is the property of some minerals to break along parallel repetitive planes of weakness to form smooth, flat surfaces. 6. Fracture - Some minerals may not have cleavages but exhibit broken surfaces that are irregular and non- planar. 7. Specific Gravity - It is the ratio of the weight of a mineral to the weight of an equal volume of water. MINERAL GROUPS 1. Silicates – minerals containing 2 of the most abundant elements in the Earth’s crust, namely, silicon and oxygen. When linked together, these two elements form the silicon oxygen tetrahedron – the fundamental building block of silicate minerals. 2. Oxides – minerals containing Oxygen anion (O2-) combined with one or more metal ions. 3. Sulfates – minerals containing Sulfur and Oxygen anion (SO4)- combined with other ions. 4. Sulfides – minerals containing sulfur anion (S2)-combined with one or more ions. Some sulfides are sources of economically important metals such as copper, lead and zinc. 5. Carbonates – minerals containing the carbonate anion (CO3)2- combined with other elements. 6. Native Elements – minerals that form as individual elements. a. Metals and Inter-metals – minerals with high thermal and electrical conductivity, typically with metallic luster, low hardness (gold, lead) 5 b. Semi-metals – minerals that are more fragile than metals and have lower conductivity (arsenic,bismuth) c. Nonmetals – nonconductive (sulfur, diamond) 7. Halides – minerals containing halogen elements combined with one or more elements. ROCKS - Rocks are an aggregate of minerals. A rock can be composed of a single mineral or more commonly composed of an aggregate of two or more minerals. TYPES OF ROCKS Sedimentary - Sedimentary rocks are formed from particles of sand, shells, pebbles, and other fragments of material.. Gradually, the sediment accumulates in layers and over a long period of time hardens into rock. - The process by which these unconsolidated rocks solidify is called lithification. Metamorphic - Metamorphic rocks are formed under the surface of the earth from the metamorphosis (change) that occurs due to intense heat and pressure (squeezing). Igneous - Igneous rocks are formed when magma (molten rock deep within the earth) cools and hardens. Ways of solidification of igneous rocks: 1. Below the surface slow cooling magma (intrusive or plutonic igneous rock)- good crystallization e. g. granite, diorite, and syenite 2. On the surface by fast cooling lava (volcanic or extrusive rock)- no visible crystals e.g basalt and andesite 3. On the surface that is erupted (pyroclastic rocks: ignimbrite, and pumice) Module 3 MINERAL RESOURCES MINERAL DEPOSITS - are naturally occurring accumulations or concentrations of metals or minerals of sufficient size and concentration that might, under favourable circumstances, have economic value. ORE - naturally-occurring material from which a mineral or minerals of economic value can be extracted MINERAL RESOURCES - form the basis for practically all everyday objects – from toothpaste to mobile phones, from paper to PC. Types of Mineral Resources Metallic Minerals show a metallic shine in their appearance Non-metalic Minerals Minerals appear with a nonmetallic shine or luster FORMATION OF A MINERAL RESOURCE 1. Magmatic Ore Deposits - valuable substances are concentrated within an igneous body through magmatic processes such as crystal fractionation, partial melting and crystal settling. 2. Hydrothermal Ore Deposits - concentration of valuable substances by hot aqueous (water-rich) fluids flowing through fractures and pore spaces in rocks 3. Sedimentary Ore Deposits - Some valuable substances are concentrated by chemical precipitation coming from lakes or seawater 4. Placer Ore Deposits - Deposits formed by the concentration of valuable substances through gravity separation during sedimentary processes 5. Residual Ore Deposits - A type of deposit that results from the accumulation of valuable materials through chemical weathering processes Module 4 ENERGY RESOURCES Energy is simply defined as the capacity to do work, while resource is the general term referring to item which is used for a specific purpose. TYPES OF ENERGY RESOURCES Renewable Resources - Can be replenished or regenerated on a human time scale. Geothermal Energy energy comes from the heat generated from the Earth. As you descend deeper into the Earth's crust, underground rock and water become hotter. low temperature geothermal energy medium temperature geothermal high temperature geothermal Hydrothermal Energy - energy comes from the moving water. The kinetic energy generated by moving water has been used by humankind for centuries, to drive watermills that produce mechanical energy Wind Energy - energy comes from the movement of the air which is caused by differences in atmospheric pressure Solar Energy - It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power Nonrenewable Resources - Cannot be replenished or regenerated on a human time scale. Fossil Fuels Coal - is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. - Types of coal Lignite is 65 to 70% carbon and 63 to 53% volatile matters Peat consists of partially decomposed vegetation Petroleum - comes from the Latin words “petra” which means “rock” and “oleum” which means “oil”. Natural Gas - is a hydrocarbon mostly made up of methane Nuclear Energy Coalification is the formation of coal from plant material by the processes of diagenesis and metamorphism. Also known as bituminization or carbonification. It all starts with a swamp on the edge of a sedimentary basin, such as a lagoon or a lake. Geothermal Energy energy comes from the heat generated from the Earth. As you descend deeper into the Earth's crust, underground rock and water become hotter.  low temperature geothermal energy medium temperature geothermal high temperature geothermal MODULE 5 WATER RESOURCE THE HYDROLOGIC CYCLE - Also known as water cycle is the movement of water around the Earth’s surface and its subsystems EARTH’S WATER RESOURCES Saltwater Reservoir Includes oceans and seawater Its saltiness is due to the salinity, due to the presence of sodium and chlorine ions Provides food, used for transportation, and regulate climate Freshwater Reservoir Most of it are stored in glaciers, ice sheets, and permafrost Glaciers and Ice Sheets - permanent body of ice, which consists largely of recrystallized snow Permafrost - soil, rock, or sediment that is frozen for more than two consecutive years. Surface Water Reservoir Includes streams, lakes, wetlands, floods Represents 0.3% of Earth’s total water resource Utilized for irrigation, drinking, hydropower, transport, and recreation Groundwater Largest reservoir of freshwater on Earth Constituting 30.1% of total freshwater Water found underground in the cracks and spaces in soil, sand and rock, called as aquifers ACTIVITIES AFFECTING THE QUALITY OF WATER 1. Population Growth 2. Movement of large number of people from the countryside to towns and cities 3. Demands for greater food security and higher living standards 4. Increased competition between different uses of water resources 5. Pollution from factories, cities and farmlands LAWS AND REGULATIONS ENACTED FOR THE PROTECTION, CONSERVATION, AND MANAGEMENT OF FRESHWATER RESOURCES Presidential Decree (PD) No. 424 of 1974 - Creation of National Water Resources Council (NWRC) to coordinate and integrate water resources development. PD No. 1067 (1976) - Water Code that consolidates laws governing the ownership, utilization, development, conservation, and protection of water resources. Executive Order (EO) No. 222 (1995) - Establishment of Presidential Committee on Water Conservation and Demand Management that prepares a nationwide Water Conservation Plan  Republic Act (RA) No. 8041 - National Water Crisis Act of 1995 that addresses country water problems. The Philippine Clean Water Act of 2004 - Provided a comprehensive water quality management. MODULE 6 SOIL RESOURCES Soil is an essential component of Earth that has enabled life to exist on the planet and continues to support it. It forms the pedosphere FACTORS AFFECTING SOIL FORMATION 1. Parent Material - it is important in soil formation because its chemistry and type will determine the soil that will be formed. 2. Climate–Temperature, rainfall, and moisture affects the pattern and intensity of soil-forming processes such as weathering, leaching, transportation and distribution 3. Topography- the gradient of the slope affects water flow and erosion and moisture as slopes facing the sun are warmer. 4. Biological Factors- Organisms such as plants, animals, microorganisms, and humans affect soil formation. 5. Time- the formation of soil is a long and continuous process which may take hundreds to thousands of years depending on the climate and environment. Soil Texture - relative proportion of particle sizes in soil (sand, silt, clay) - soil is made up of mixture of these particles, their proportion affects the soil’s porosity and water retention - smallest particle: sand - large particles (> 75mm) are called gravel and rock - ideal soil for agricultural use is loam due to its good aeration and drainage Soil Layers A: An A horizon is a mineral horizon B: A B horizon is typically a mineral subsurface horizon and is a zone of accumulation, called illuviation. C: A C horizon consists of parent material O: An O horizon has at least 20% organic matter by mass. E: The E horizon appears lighter in color than an associated A horizon (above) or B horizon (below). R: An R layer is bedrock. HUMAN ACTIVITIES THAT DEGRADE THE SOIL QUALITY Agricultural Depletion Overgrazing Animals Deforestation Mining Urbanization Recreational Activities WAYS TO CONSERVE SOIL RESOURCE 1. Increase soil organic matter 2. Keep the soil covered and vegetated 3. Avoid excessive tillage 4. Manage pests and nutrient efficiently 5. Promote crop rotation 6. Reduce erosion and prevent soil compaction