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NATURAL RESOURCES Natural Resources And Human Histor y Over one hundred sixty thousand years ago, our ancestors probably began to use flint, chert, and obsidian to make tools Metals were first used more than 20,000 years ago Copper and gold were the earliest metals used By 6000 years ago, our ancestors extracted copper by smelting Before another thousand years had passed, they had discovered how to smelt lead, tin, zinc, silver, and other metals Natural Resources And Human Histor y The technique of mixing metals to make alloys came next Bronze was composed of copper and tin Pewter was composed of tin, lead, and copper The smelting of iron came much later—about 3300 years ago The first people to use oil instead of wood for fuel were the Babylonians, about 4500 years ago The first people to mine and use coal were the Chinese, about 3100 years ago What is a natural resource? Any form of matter or energy obtained from the physical environment that meet human needs Those things that people come in contact with that may be used to perform any useful function Objects, materials, creatures, or energy found in nature that can be put to use by humans Natural Resources Natural resources are things that are found in nature and useful to people We need natural resources to live Natural resources are things that people and animal can’t live without Natural Resources Water is a natural resource We can not live without it! Natural Resources Other natural resources are plants and soil Natural Resources Animals and fish are also natural resources Natural Resources Some natural resources like oil and coal will be used up if we are not careful Natural Resources Natural resources can be made into things we use Mismanagement of renewable resources may turn them into nonrenewable Over-pumping groundwater ruins vegetation creating deserts Clear cutting forest & not replanting Nonrenewable Natural Resources: Not replaced in a useful time frame Are formed FAR more slowly than we use them (they can & will run out) Mineral ores, fossil fuels (coal, oil, natural gas) The maximum rate at which a renewable resource can be used without impairing or damaging its ability to be renewed is called its maximum sustained yield If this yield is exceeded a potentially renewable resource is then converted to a nonrenewable resource Finding Substitutes and Alternatives for Scarce Mineral Resources Recycling involves collecting and remelting or reprocessing a resource, whereas reuse involves using a resource over and over again in the same form Resources can be classified on biotic and abiotic: Biotic resources are derived from animals and plants (livingworld) Abiotic resouces are derived from the non-living world e.g land, water, and air Mineral and power resources are also abiotic resources some are derived from nature Resources can be classified on Earth resources: Three major categories of Geologic Resources: Energy Metallic Non-metallic All are non-renewable resources (time needed to create >>> time needed to consume) Earth Resources can be classified: Perpetual or Renewable Exhaustible or Direct solar energy Nonrenewable Indirect effects related to Minerals hydrological cycle, e.g., wind, Metallic: tides, running water etc Ferrous, Nonferrous Potentially (or Polymetallic), Exhaustible/ Precious Renewable Nonmetallic: Fresh Air Industrial, Gemstones Fresh Water Energy Resources Fertile Soil Biodiversity Radioactive Minerals Fossil Fuels: Coal, Oil and Natural Gas Energy Resources Fossil Fuels Coal, petroleum, natural gas, oil shale Nuclear Fuels Uranium Earth’s Heat (geothermal power) Solar-derived Energy Streams, winds, ocean currents, waves, sunlight Tides The Society Page Metallic Resources There three categories namely Ferrous Metals, Precious metals and Base Metals Ferrous metals Precious metals include: Gold, Platinum, Silver Base metals include: Bauxite, aluminium, cobalt, copper, lead, magnesium, zinc, nickel, molybdenum Metallic Resources Metallic Resources Abundant Metals Iron, aluminum, manganese, titanium, silicon, magnesium Produced by variety of geologic processes Supplies for future adequate Not distributed uniformly Scarce Metals Comprise less than 0.1% of Earth’s crust (rare conditions concentrate them) Fewer deposits, so supplies are more precarious 30 Geochemically Abundant Elements (GAE) Elements comprise > 0.1% (by weight) of the crust Form as principal component in minerals within common rocks – i.e iron (Fe) Fe2O3 Form very large deposits Form rock deposits Geochemically Scarce Elements (GSE) Elements that comprise < 0.1% (by weight) of the crust Do not form as principal component in minerals within common rocks, usually occur as a substitute in rock forming minerals Form small deposits Ore minerals include sulfides, native elements, etc Metallic Resources Formed by: Hydrothermal fluid circulation (e.g Pb/Ag veins in Idaho) Crystallization in magmas (e.g Pt/Cr layers in South Africa) Ground water leaching (e.g Cu in Montana) Stream concentration (e.g placer deposits in California) All require a concentration mechanism! Non-Metallic Minerals These are Construction minerals, industrial minerals, precious stones: Construction minerals (brick, stones, cement, clay, crushed rock, sand) Industrial minerals (kaolin, magnesium, salt, sulphur, potash) Precious stones (Diamonds, Tanzanite and other gemstones) 34 [...]... the Earth Natural resource classification Natural resources are often classified : Renewable and Nonrenewable Resources Renewable resources can be replenished over fairly short spans of time, such as months, years, or decades Nonrenewable resources take millions of years to form and accumulate Major types of Natural Resources Perpetual Resources Renewable Resources Non-renewable Resources. .. beliefs, and the environmental effects of finding and using it On the basis of their stages of developments, resources can be classified into both Actual and Potential resources: The resources pass through various stages of development before they are actually available The resources held actually in stock are called Actual resources Even the actual source of resources may not be possible to be used... The portion that can be used profitably with the help of available technology is termed as Potential resourcs The size and quantity of a potential resource may change with changes in technology and time Natural capital Natural resources are natural capital converted to commodity inputs to infrastructural capital processes They include soil, timber, oil, minerals, and other goods taken more or less...Usefulness Changes Things that affect our definition of usefulness Religion- Hindu- cattle Custom- Dogs as food source Technology and Science Resources or natural resources are any form of matter or energy obtained from the physical environment that meet human needs This definition of natural resources is not as simple as it appears Most resources are created by human ingenuity Oil was once... Substitutes and Alternatives for Scarce Mineral Resources Recycling involves collecting and remelting or reprocessing a resource, whereas reuse involves using a resource over and over again in the same form Resources can be classified on biotic and abiotic: Biotic resources are derived from animals and plants (livingworld) Abiotic resouces are derived from the non-living world e.g land, water, and air... non-living world e.g land, water, and air Mineral and power resources are also abiotic resources some are derived from nature Resources can be classified on Earth resources: Three major categories of Geologic Resources: 1 2 3 Energy Metallic Non-metallic All are non-renewable resources (time needed to create >>> time needed to consume) Earth Resources can be classified: Perpetual or Renewable... ground, and separate it by distillation into various components such as gasoline, home heating oil, and road tar Similarly, coal and uranium were once useless rocks Something may become useful or useless for human needs as a result of changes in the technology of resource extraction and processing Whether something is classified as a resource depends on technology, economics, cultural beliefs, and the... Gemstones Fresh Water Energy Resources Fertile Soil Biodiversity Radioactive Minerals Fossil Fuels: Coal, Oil and Natural Gas 1 Energy Resources Fossil Fuels Coal, petroleum, natural gas, oil shale Nuclear Fuels Uranium Earth’s Heat (geothermal power) Solar-derived Energy Streams, winds, ocean currents, waves, sunlight Tides The Society Page 2 Metallic Resources There three categories... Renewable Resources Non-renewable Resources 1 Renewable Natural Resources: Replenished over short periods of time Sun, wind, water, trees perpetually available Timber, water, soil Take months or years to replenish themselves If we are not carefully we can use these up or destroy them so they can’t replenish themselves Mismanagement of renewable resources may turn them into nonrenewable Over-pumping... categories namely Ferrous Metals, Precious metals and Base Metals Ferrous metals Precious metals include: Gold, Platinum, Silver Base metals include: Bauxite, aluminium, cobalt, copper, lead, magnesium, zinc, nickel, molybdenum Metallic Resources Metallic Resources Abundant Metals Iron, aluminum, manganese, titanium, silicon, magnesium Produced by variety of geologic processes Supplies for future