EARTH SCIENCE Quarter 1 Handout 1 PDF

EARTH SCIENCE QUARTER 1 – HandOut 1: Earth’s Characteristic to Support Life What makes a planet habitable? 1. TEMPERATURE influences how quickly atoms and molecules move: Life seems to be limited to a temperature...

EARTH SCIENCE QUARTER 1 – HandOut 1: Earth’s Characteristic to Support Life What makes a planet habitable? 1. TEMPERATURE influences how quickly atoms and molecules move: Life seems to be limited to a temperature range of -15oC to 115oC. In this range, liquid water can still exist under certain conditions. 2. ATMOSPHERE Traps heat, shields the surface from harmful radiation, and provides chemicals needed for life, such as nitrogen and carbon dioxide. Of the solid planets & moons, only Earth, Venus, & Titan have significant atmospheres. Mars’ atmosphere is about 1/100th that of Earth’s, too small for significant insulation or shielding. 3. ENERGY Organisms use light or chemical energy to run their life processes. 4. NUTRIENTS Used to build and maintain an organism’s body. All solid planets & moons have the same general chemical makeup, so nutrients are present. Those with a water cycle or volcanic activity can transport and replenish the chemicals required by living organisms. On the surface: Earth has a water cycle, an atmosphere, and volcanoes to circulate nutrients. Venus, Titan, Io, and Mars have nutrients and ways to circulate them to organisms. Why is the earth special? 1. proximity to the sun—neither too much heat nor too little 2. system of plate tectonics that enables the carbon-silicate cycle regulating temperature 3. earth has the right size (Earth is large enough to hang on to its atmosphere, but not so large to hold on to too much atmosphere and consequently too much heat.) 4. presence of Jupiter 5. having water in its liquid form at the surface, in an amount conducive to life evolving. 6. Considered as the only living planet which is composed of four subsystems known as the biosphere, atmosphere, lithosphere, and hydrosphere where matter and energy flow to make life on earth possible. Right distance from the sun + Right type + Right size + Right Atmosphere + Right Composition or Elements = L I F E (Goldilocks Principle) EARTH SUBSYSTEMS A system is a group of related objects or parts that work together to form a whole. The Earth system is all of the matter, energy, and processes within Earth’s boundary. Earth is a complex system made of living and nonliving things, and matter and energy continuously cycle through the smaller systems. A. ATMOSPHERE - The atmosphere is the thin gaseous layer that envelopes the lithosphere. - It also traps some energy from the sun, which helps keep Earth warm enough for living things to survive and multiply. (Greenhouse Effect) - Acts as shield from radiation - It is about: 78% nitrogen, 21% oxygen, and 1% other gases. (Minor gases in the atmosphere include argon, carbon dioxide, and water vapor.) LAYERS OF THE ATMOSTPHERE: 1. Troposphere - It is the lowest layer where the weather forms. 2. Stratosphere - extends to 50 km above the Earth's surface. The ozone layer that protects the Earth from the Sun's harmful UV radiation is found in this layer. 3. Mesosphere - It protects the Earth from the impact of space debris. Meteors usually burn up in this region as they approach our planet. 4. Thermosphere - extends up to 600 km above the Earth's surface. It has charged particles that are affected by the Earth's magnetic field (Ionosphere). The particles create the Auroras or Northern and Southern lights. 5. Exosphere - It is the farthest layer. It extends to about 10 000 km above the Earth's surface. B. BIOSPHERE - The biosphere is the set of all life forms on Earth. - It covers all ecosystems—from the soil to the rainforest, from mangroves to coral reefs, and from the plankton-rich ocean surface to the deep sea C. LITOSPHERE - The lithosphere is the solid, outer part of the Earth. - It includes the brittle upper portion of the mantle and the crust, the outermost layer of Earth’s structure. D. HYDROSPHERE - Hydrosphere is composed of all the water on Earth in any form: water vapor, liquid water, and ice. - The cryosphere is made up of all of the frozen water on Earth, such as glaciers, ice caps and icebergs. EARTH SYSTEM SCIENCE - The study of the interactions between and among events and Earth’s spheres COMMON ROCK-FORMING MINERALS o Minerals - These are the basic building blocks of rocks. Minerals are naturally occurring, inorganic solid with orderly crystalline structure and a definite chemical composition Characteristics of Minerals: 1. Naturally occurring - Minerals are formed by natural, geologic processes. They are not man-made. 2. Solid earth material - Only crystalline substances that are solid at temperatures encountered at Earth’s surface are considered minerals 3. Generally inorganic - Traditionally, minerals are not biological in origin. They are not formed from living things or the remains of living things 4. Definite Chemical Structure - Minerals are crystalline substances, which means their atoms are arranged in an orderly, repetitive manner. 5. Definite Chemical Formula - The elements that make up the minerals are combined in definite proportions Quartz has the formula which indicates that quartz consists of silicon (Si) and oxygen (O) atoms in a ratio of one-to-two. Properties of Minerals: 1. Color - Although probably the most obvious feature, color is the least diagnostic physical property of most minerals. Color can vary due to chemical impurities and oxidation (exposure to air and water changing the color of the mineral) 2. Streak - Streak is the color of a powdered mineral and is considered to be the true color of a mineral. Different specimens of a mineral may have different colors, but the powdered streak is constant. 3. Luster - describes how light is absorbed or reflected by a mineral surface, which affects the mineral’s appearance. Luster can be metallic or non-metallic. 4. Hardness - a measure of the resistance of a mineral to abrasion or scratching. 5. Tenacity - describes a mineral’s toughness, or its resistance to breaking or deforming. 6. Crystal Habit - The external shape of a crystal or groups of crystals is displayed as these crystals grow in open spaces. The form reflects the supposedly internal structure (of atoms and ions) of the crystal (mineral). It is the natural shape of the mineral before the development of any cleavage or fracture. 7. Cleavage - It is the property of some minerals to break along parallel repetitive planes of weakness to form smooth, flat surfaces. These planes of weakness are inherent in the bonding of atoms that makes up the mineral. 8. Fracture - is exhibited if the mineral does not have a cleavage plane, thus it exhibits broken surfaces that are irregular and non-planar EARTH SCIENCE QUARTER 1 – HandOut 2: Classification of Rocks and the Minerals Important to Society A rock is a naturally occurring solid aggregate of minerals, sometimes with nonmineral solid particles. Petrology is the science that is concerned with the study of rocks. CLASSIFICATION OF ROCKS 1. IGNEOUS ROCKS - Igneous rocks are formed through the cooling and solidification of magma or lava. Types: According to Formation: a. Extrusive Igneous Rocks (Volcanic) - When molten rock solidifies at the surface (example: Basalt) b. Intrusive Igneous Rocks (Plutonic) - When magma solidifies at depth (example: Granite) According to rate of cooling and texture: a. Phaneritic - Magma cools slowly beneath the earth’s surface. Individual crystals are large enough so that the materials can be identified with the naked eye. (COARSE- GRAINED) b. Aphanitic - If the lava cooled quickly on or near earth’s surface. Individual crystals are hard to see with the naked eye (FINE-GRAINED) c. Porphyritic - A combination of different crystal sizes d. Glassy - If the molten rock crystallizes immediately, the result is a rock that shines like glass According to color and composition: Color varies with silica content. Silica-rich minerals such as quartz and feldspar are light-colored. Silica-poor mineral such as amphibole, biotite mica are dark-colored.  2. SEDIMENTARY ROCKS - Sedimentary rocks are formed by the deposition and cementation of mineral or organic particles on the floor of oceans and other bodies of water at the Earth surface. They can be classified as clastic, chemical and organic sedimentary rock. Types: a. Clastic sedimentary rocks - It is formed from the mechanical weathering debris of rocks. Examples are breccia, conglomerate, sandstone, siltstone, and shale. b. Chemical sedimentary rocks - It is formed when dissolved materials precipitate from solution. Examples of these are rock salt, iron ore, flint, some dolomites. c. Organic sedimentary rocks - Formed from the build-up of plant or animal debris. These may contain fossils of plants and animals trapped in the sediments as the rock was formed. 3. METAMORPHIC ROCK - Metamorphic rock forms from existing rock types called “parent rock (protolith)” in the process called metamorphism, which means change in form. The original rock which can be an igneous, sedimentary or another metamorphic rock is subjected to extreme heat and pressure, causing a profound chemical or physical change. Metamorphism is a process that produces fundamental change in the mineralogy and texture of the rock. Contact metamorphism - Rocks are heated by nearby magma which result to a change in composition. Regional metamorphism - Large pieces of the Earth’s crust collide and the rock is deformed and chemically changed by heat and pressure Types: a. Foliated metamorphic rock - Formed through pressure due to compression of rocks that create bands called foliation. b. Nonfoliated metamorphic rock – It has no foliation or bands. Examples of metamorphic rocks: 1. Marble (parent rock: limestone) 2. Quartzite ( parent rock: sandstone) 3. Gneiss ( parent rock: granite) The rock cycle shows how one type of rocks transform to other types of rocks.  EARTH SCIENCE QUARTER 1 – HandOut 3: Mining and Development of Mineral Resources; and Fossil Fuels Mining refers to a set of processes through which useful resources are withdrawn from a stock of any nonrenewable resource. 1. Exploration - Looking for the ore body – - Ores are naturally-occurring materials that can be profitably mined. Ore bodies are unevenly distributed throughout Earth’s crust. This is the main reason why a country will never be self-sufficient in terms of natural resources and supplies. Profitability determines an ore’s value. A mineral or rock body containing high concentration of the required resource may not be considered a good ore if it is too expensive to mine, too far to transport to a market, or if the additional costs (labor, mine management, and environmental protection) outweigh the potential the profit to be made If an area looks promising, a drill is moved to the site. The drill goes deep into the Earth’s crust removing long cylinders of rock called cores. 2. Environmental Assessment and Approval It is at this stage that a company proposing a mine project includes a complete reclamation, satisfactory land-use end goal, and monitoring plan. The proposal must be submitted to government agencies (the Environmental Assessment office) at the provincial and federal government levels for approval. 3. Designing and Constructing the Mine Engineers and scientists work hard hand in hand to create the appropriate mine and operational design, and proceeds with the construction once all the necessary permits are acquired from the government and local communities 4. Operation Extraction - High grade ores are separated from the rest of the deposit Processing - These are the steps required to change raw, broken ore into useable material or to liberate and separate valuable minerals from waste rock. Mining Methods: a. Surface Mining Methods are used when a mineral resource is at or near the Earth's surface. Underground Mining Methods are used when the mineral deposit is too deep underground to be practical and economical to mine from the surface. 5. Reclamation-Mine Site Decommissioning Closure of the depleted mine; the mine site is cleaned up and reclaimed or rehabilitated for other purposes. Some Issues Involved in Mining: Groundwater and surface contamination Collapse of unfilled tunnels Destruction of landscapes via pit or strip mining. Pollution from smelting – smelters without pollution controls have been known to kill nearly every tree within 10-mile radius Energy intensive – 5-10% world of energy use goes toward mining and refining mineral resources FOSSIL FUELS Fossil fuel which are nonrenewable sources of energy are presently the world’s primary energy source. They are derived from the remains of prehistoric plants and animals that died millions of years ago and were buried under the right conditions to form fossil. Since this fuel originated from the remains of once living organisms, fossil fuels composed mainly of high content of carbon and hydrogen, called hydrocarbons. There are three main categories of fossil fuels: coal oil, and natural gas. The different fossil fuels formed depending on the action of four factors: 1. organic matter source 2. pressure  3. time 4. heat Fossil fuels formation started during the Carboniferous era (359 million to 299 million years ago) of the Paleozoic era. 1. COAL - Coal is a solid fossil fuel formed from ancient plants—including trees, ferns, and mosses—that grew in swamps and bogs or along coastal shorelines and were subjected to high pressure and heat over a long period of time. Coal Formation: a. Peat - is considered the precursor form of coal, contains less than 60% carbon and composed wholly of volatile matter. If left to itself, it burns like wood, gives less heat, emits more smoke and leaves a lot of ash. b. Lignite - is also known as brown coal and is composed of 65-70% carbon and 53-63% volatile matter. It undergoes spontaneous combustion c. Bituminous coal - is a sedimentary rock composed of 70-86% carbon and 31-46% volatile matter. Calorific value is very high due to high proportion of carbon and low moisture. d. Anthracite - is deemed the highest form of coal due to its carbon content ranging from 86-98% with 3-8% volatile matter. - Ignites slowly and burns with a nice short blue flame. 2. PETROLEUM AND NATURAL GAS Petroleum is a fossil fuel derived from large quantities of microscopic aquatic organisms such as algae and planktons. The remains of these organisms remain settled to the sea or lake bottoms millions of years ago and were buried beneath fine sediments anoxic conditions. With increasing pressure and temperature due to continuous burial, the organic matter in these organisms transform into a waxy material known as kerogen and eventually into hydrocarbons through the process of catagenesis. Kerogen is the insoluble organic portion of sedimentary rocks. It is a waxy mixture of different organic materials (like algae and pollen) and is insoluble in organic solvents because of the high molecular weight of the compounds present. Petroleum forms within a specific depth, pressure, and temperature range known as “oil window”. Below this temperature range (50ºC to 150ºC) kerogen is not transformed into hydrocarbons. On the other hand, if the temperature increases beyond oil window, oil is converted into natural gas in a process called thermal cracking. Natural gas is a hydrocarbon mostly made up of methane (CH4). Methane is a simple chemical compound that is made up of carbon and hydrogen atoms. This gas is lighter than air and is highly flammable. Some Environmental Issues Acid rain Emissions of ash particles Global warming Petroleum recovery and transportation Coal mining EARTH SCIENCE QUARTER 1 – HandOut 4: Sources of Energy: Geothermal and Hydroelectric RENEWABLE ENERGY RESOURCES: Renewable energy is often referred to as clean energy. It is energy resulting from natural resources that replenish themselves over a period without exhausting the Earth's resources. GEOTHERMAL ENERGY – harnessing heat energy from the earth HYDROELECTRIC POWER harnesses the kinetic energy of running water. Earth’s water budget - the total amount of water in the planet. Note: The earth’s water budget is CONSTANT. WATER RESOURCES: 1. SALTWATER RESERVOIR - An ocean is a vast body of saline water. There is only one global ocean and it covers 71% of Earth. 2. FRESHWATER RESERVOIR: a. Glaciers and Ice Sheet - contributes to the highest percentage of freshwater resource in the planet b. Permafrost c. Surface Water Reservoir 1. Streams and Rivers 2. Lake 3. Wetland a. MARSH – shallow wetland around lakes, streams and oceans where grasses and reeds are the dominant vegetation. (example: Candaba, Pampanga marsh) b. SWAMP – wetland with lush trees and vegetation found in low-lying areas beside slow- moving rivers. Low-oxygen environment. (example: mangrove forests) c. ESTUARY – partly enclosed body of water where freshwater from stream meets the saltwater from the sea.  d. Groundwater - is freshwater found in the rock and soil layers beneath the surface. It is the largest reservoir of liquid freshwater on Earth. EARTH SCIENCE QUARTER 1 – HandOut 5: Human Activities that Affect Water and Soil Resources Water resources around the world are threatened because of human activities. In the Philippines, many rivers and other water resources have been declared as biologically dead. Human Activities that Affect Water Resources 1. Agricultural Activities 2. Aquaculture 3. Excessive extraction of groundwater that causes the water table to sink. 4. Pollution 5. Individual activities Soil is the solid material on the Earth’s surface that comes from broken down rocks, organic matter such as decayed animal and plant life, water and air through the interaction of biological activities and weather with the primary geologic formation. The following is the average composition by volume of the major soil ingredients: 45% inorganic minerals (clay, silt, gravel, stones) 25% water (the amount varies depending on the precipitation and the water-holding capacity of the soil) 25% air (important for living organisms) 5% organic matter or humus Soil Profile O – (Humus or Organic) It is mostly organic matter such as decomposing leaves. The O horizon is thin in some soils, thick in others, and not present at all in others. A - (Topsoil) It is a mixture of minerals with organic matter incorporated where plants and other organisms live. E – (Eluviated) It is composed of clay, minerals, and organic matter, leaving a concentration of sand and silt particles of quartz or other resistant materials and often found in older soils and forest soils. B – (Subsoil) It is rich in minerals that moved down from the A or E horizons. C – (Parent material) The deposit at Earth’s surface from which the soil developed. R – (Bedrock) Made of mass of rock such as granite, basalt, quartzite, limestone or sandstone that forms the parent material for some soils – if the bedrock is close enough to the surface to weather. This is not soil and is located under the C horizon. Human Activities That Affect Soil Quality and Quantity 1. Agricultural Depletion - Farming can degrade the topsoil and lead to an increase in erosion. 2. Overgrazing Animals - Grazing animals are animals that live on large areas of grassland. Overgrazing destroys natural vegetation and causes the soil to wash or blow away more easily. 3. Deforestation 4. Mining operations 5. Development and Expansion 6. Recreational activities, like driving vehicles off-road or hiking EARTH SCIENCE QUARTER 1 – HandOut 6 & 7: The Waste We Produce The United Nations environment program defines waste as “substance or objects, which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law”. Types: 1. SOLID WASTE - This can be garbage or refuse in solid forms from domestic, commercial and industrial wastes. It is the most abundant type of waste produced. 2. LIQUID WASTE - Liquid waste includes sewage as well as wastewater from industrial processes such as food and agricultural processing, and manufacturing. 3. GASEOUS WASTE - Mostly generated by human activity.  Classification of Waste According to Origin 1. Municipal/ Urban Solid wastes include household garbage, rubbish, construction & demolition debris, sanitation residues, packaging materials, trade refuges etc. are managed by any municipality 2. Industrial wastes are liquid and solid wastes that are generated by manufacturing & processing units of various industries like chemical, petroleum, coal, metal gas, sanitary & paper etc. 3. Agricultural wastes are generated from farming activities. These substances are mostly biodegradable. 4. Fishery wastes are produced due to fishery activities. These are extensively found in coastal & estuarine areas. 5. Radioactive wastes are byproducts of nuclear processes. Sometimes industries that are not directly involved in nuclear activities, may also produce some radioactive wastes, e.g. radio-isotopes, chemical sludge. 6. E-wastes or electronic wastes generated from any modern establishments. They may be described as discarded electrical or electronic devices. Some electronic scrap components may contain contaminants such as Pb, Cd, Be or brominated flame retardants. 7. Bio-medical wastes: Solid or liquid wastes including containers, intermediate or end products generated during diagnosis, treatment & research activities of medical sciences. Other Classification: 1. Nonbiodegradable - Items which cannot be degraded such as plastics, bottles, old machines, cans etc. 2. Biodegradable - Materials which can be degraded such as paper, wood, fruits and others. 3. Hazardous waste - Substances unsafe to use commercially, industrially, agriculturally, or economically and have any of the following properties- ignitability, corrosiveness, reactivity & toxicity. 4. Non-hazardous waste - Substances safe to use commercially, industrially, agriculturally, or economically and do not have any of those properties mentioned previously. These substances usually create disposal problems. WASTE MANAGEMENT HIERARCHY OF OPTIONS Waste disposal can be defined as any process used to discard unwanted substances or materials. Improper Waste Disposal 1. Incineration is the burning of waste materials at high temperatures to transform them into gases or residue 2. Landfill refers to a cost-effective method of waste disposal that involves burying the waste in the land. 3. Open Dumping is a simple and inexpensive method which involves the deliberate disposal of garbage in an open space. 4. Ocean Dumping occurs when sewage, garbage, construction debris, hazardous chemicals etc. are intentionally discarded at sea by ships, aircrafts and other man-made machines. What are the effects of Improper Waste Disposal on Public Health? 1. Chemical Poisoning 2. Infections 3. Diseases 4. Accidents What are the effects of Improper Waste Disposal on the Environment? 1. Global Warming 2. Pollution 3. Loss of Biodiversity 4. Contamination