Chapter 14 Review
The environmental effects of gold mining can harm the environment in many negative ways. Gold miners removed enough rock to equal the weight of 50 automobiles to extract a little amount of gold. The leftover waste is piled near the mine sites and can pollute the air and nearby surface water. Mining companies also created a new mining technology called cyanide heap leaching to level entire mountains of rock. In order for them to extract the gold, they spray a solution of highly toxic cyanide salts. This cyanide is extremely toxic to birds and mammals drawn to these ponds in search of water and they can leak into the rivers posing as a threat to fish and other life forms.
Geology is the science devoted to the study of dynamic processes occurring on the earth’s surface and in its interior. The core is the earth’s innermost zone. The mantle is a thick zone surrounding the core. The crust is the outermost and thinnest zone of the earth. The tectonic plates are various sized areas of the earth’s lithosphere that move slowly around with the mantle’s flowing asthenosphere. The lithosphere is the outer shell of the earth, composed of the crust and the rigid, outermost part of the mantle outside the asthenosphere. A transform vault is an area where the earth’s lithospheric plates move in opposite but parallel directions along a fracture in the lithosphere. Weathering is the physical and chemical processes in which solid rock exposed at earth’s surface is changed to separate solid particles and dissolved material which can then be moved to another place as sediment. Its important because it is part of the rock cycle and the process releases nutrients and minerals to the soil and water for plants and animals to use. A volcano is a vent or fissure in the earth’s surface through which magma, liquid lava, and gases are released into the environment. The nature and effects of a volcanic eruption are driven by buoyancy and gas pressure the molten rock, which is lighter than the surrounding solid rock forces its way upward and may ultimately break through zones of weaknesses in the Earth's crust. If so, an eruption begins, and the molten rock may pour from the vent as non-explosive lava flows, or if may shoot violently into the air as dense clouds of lava fragments. Larger fragments fall back around the vent, and accumulations of fall-back fragments may move downslope as ash flows under the force of gravity.eruptions can come close to human settlement and can destroy properties or lives. Also places close to volcanic activities tend to have higher potential for geothermal energy, which can be an advantage to the towns and cities. Lava and ash breakdown can soils that are rich in nutrients, and become good areas for planting. An earthquake is the shaking of the ground resulting from the fracturing and displacement of rock, which produces a fault, or from subsequent movement along the fault. The nature and effects of an earthquake are when stress, building up within rocks of the earth's crust, is released in a sudden jolt. Rocks crack and slip past each other causing the ground to vibrate. Earthquakes cause destruction towards buildings and lives. A tsunami is a series of large waves generated when part of the ocean floor suddenly rises or drops. The effects are that it can cause major destruction towards buildings and human lives and can flood lands.
A mineral (limestone) is an any naturally occurring inorganic substance found in the earth’s crust as a crystalline solid. A rock is any solid material that makes up large, natural, continuous part of the earth’s crust. A sedimentary rock (coal) is a rock that forms from the accumulated products of erosion and in some cases from compacted shells, skeletons, and other remains of dead organisms. A igneous (Basalt) rock is a rock formed when molten rock material wells up from the earth’s interior, cools, and solidifies into rock masses. A metamorphic rock (Slate) is a rock produced when a pre existing rock is subjected to high temperatures, high pressures, chemically active fluids, or a combination of these agents. A rock cycle is a cycle through which rocks change and are remade into other rocks by external processes such as weathering, erosion, deposition, lithification, and internal processes, such as melting, cooling, and crystallization. The topography of all areas of the world is shaped by the stage of the rock cycle the ground is in; many islands are covered by igneous rock as a result of volcanic activity, whereas sedimentary and metamorphic rock are commonly found on larger landmasses which is why it’s so important.
Surface mining is used where the ore or material to be extracted is located fairly close to the surface. The overlying ground cover is removed, the material is mined, and the ground cover is ordinarily replaced. Subsurface mining is used where the material is in veins deep beneath the surface, or obstructed (by rock layers, water tables, or other strata) in a way that make surface access impractical. Overburden is layer of soil and rock overlying a mineral deposit. Spoils is unwanted rock and waste materials produced when a material is removed from the earth’s surface or subsurface by mining, dredging, quarrying, or excavation. Open pit mining is removing minerals such as gravel, sand, and metal ores by digging them out of the earth’s surface and leaving an open pit behind. Striping mining is a form of surface mining in which bulldozers, power shovels, or striping wheels remove large chunks of the earth’s surface in strips. Area strip mining is the type of surface mining used where the terrain is flat. Contour strip mining is a form of surface mining used on hilly or mountainous terrain. Mountaintop removal is a type of surface mining that uses explosives,A mineral resource is the concentration of minerals in Earth's crust that can be extracted and processed relatively easily and affordably. Three examples are identified resources, undiscovered resources and reserve. An ore is part of a metal yielding material that can be economically extracted from a mineral in two parts. The difference between a high ore and a low ore is that High-grade ores contain relatively large amounts of particular minerals and low-grade ores contain lesser amounts. Reserves are resources that have been identified and from which a usable mineral can be extracted profitably at present prices with current mining or extraction technology. In the life cycle of a metal resource each step in this process uses large amounts of energy and produces some pollution and waste. The following are the steps in order: Surface mining, metal ore, separation of ore from gangue, smelting, melting metal, conversion to product and/or go back to recycling, then discarding of product. Mining, processing, and using mineral resources take enormous amounts of energy and can disturb the land, erode soil, produce solid waste, and pollute the air, water, and soil. Some environmental scientists and resource experts warn that the greatest danger from continually increasing our consumption of nonrenewable mineral resources may be the environmental damage caused by their extraction, processing, and conversion to products. Extracting and using mineral resources can disturb the land, erode soils, produce large amounts of solid waste, and pollute the air, water, and soil. massive shovels, and large machines called draglines to remove the top of a mountain to expose seams of coal underneath a mountain. Some harmful effects that happen because of mining is major pollution in the air and water. Also scarring and disruption of the land surface. Smelting is heating ores to release metals and some of the harmful effect it causes are air pollution, water pollution, liquid and solid hazardous wastes. The five nations are Canada, United States, Germany, Russia, South Africa which is the self sufficient in all key minerals, largest producer of gold, chromium and platinum Australia.
Some advantages of nanotechnology are to reduce need to mine many materials, less material and energy, reduce waste production, remove industrial pollutants, purify water. Some disadvantages of nanotechnology are to be inhaled into lungs and absorbed into bloodstream and can penetrate cell membranes including those in the brain, move across the placenta from mother to fetus and can move from nasal passages to brain, result in lung disease similar to that caused by mesothelioma, cause changes in the rate and rhythm of a rodent's heartbeat, similar to changes caused by heart diseases. Five possible options for when a mineral become economically depleted are Recycle or reuse existing supplies, Waste less, Use less, Find a substitute, Do without. Depletion time is the time it takes to use a certain fraction of the known or estimated supply of a nonrenewable resource at an assumed rate of use. Three types of depletion curves are mine, use, throw away; no new discoveries, rising prices. Another one is recycle; increasing reserves by improving mining technology, higher prices, and new discoveries. Also recycle, reuse, reduce consumption; increase reserves by improved mining technology, higher prices, and new discoveries. The conventional view on the relationship between the supply of a mineral resource and its market price is a mineral is expensive when there is little supply and is cheap with too much supply. The factors that can influence this market interaction is how expensive the price is. Some positive aspects of nanotechnology are that it can benefit the energy sector. The development of more effective energy-producing, energy-absorbing, and energy storage products in smaller and more efficient devices is possible with this technology. Such items like batteries, fuel cells, and solar cells can be built smaller but can be made to be more effective with this technology. Some negative aspects are that it nanotechnology is very expensive and developing it can cost you a lot of money. It is also pretty difficult to manufacture, which is probably why products made with nanotechnology are more expensive. Some pros and cons of the U.S general mining law of 1872 are that it was cheap for land buyers because US wanted mineral expansion. Some cons were that land was used for other purposes and the government lost money because the land was so cheap. Also the environment was harmed because they didn't have money to pay for reclamation until 1992. opportunities for mining lower-grade ore are the development of new earth-moving equipment, improved technologies for removing impurities from ores, and other technological advances in mineral extraction and processing that can make lower-grade ores more accessible, sometimes at lower costs. Advantages of biomining are that it doesn't disturb environment, reduces air and water pollution associated with removing metal from metal ores. Disadvantages of biomining are that it slow and only works with lower-grade ores. opportunities of getting minerals from ocean are deposits of minerals in sediments on shallow continental shelf and adjacent shorelines, remote-controlled underwater equipment, manned sea craft, vacuum pipes, underwater mining machines. limitations of getting minerals from ocean are low concentrations of elements and compounds means the time and energy spent getting them is worth more, the sediments stirred up can harm organisms that feed by filtering seawater, the materials in deep-ocean areas belong to no one in particular.
Some opportunities are Ceramics and plastics being used as replacements for metals. Nanotechnology may lead to development of substitutes. Grancrete: Styrofoam and ceramic. Plastic for pipes, Plastic and composite materials for automobile and aerospace industry, Plastic and gels for superinsulation, Plastics from plant materials. Limitations are plastics that require the use of fossil fuels, which are nonrenewable and have their own environmental impacts. Ways to use nonrenewable mineral resources more sustainably are to redesign equipment and processes and use a cleaner production that saves money. The pollution prevention pays program of the minnesota mining and manufacturing company redesigns its equipment and processes, used fewer hazardous raw materials, identified toxic chemical outputs and recycled or sold them as raw materials to other companies. They also began making more non polluting products. Industrial ecosystem is is the study of material and energy flows through industrial systems. The global industrial economy can be modeled as a network of industrial processes that extract resources from the Earth and transform those resources into commodities which can be bought and sold to meet the needs of humanity. The industrial ecosystem operating in denmark is where an electric plant power plant and nearby industries, farms and homes are collaborating to save money and reduce their outputs of waste and pollution. They exchange waste outputs and convert them into resources. This cuts pollution and wastes and reduces the flow of nonrenewable mineral and energy resources through their economy. The relationship between gold mining and the four scientific principles of sustainability are that the first principle of sustainability could enable the use of solar energy to produce electricity for extracting and processing mineral resources and for a host of other environmentally beneficial processes that require electricity. The second principle of sustainability applies to recycling mineral resources and reducing unnecessary resource use and waste. The last two principles of sustainability help implement strategies that will reduce both the need for mining and its resulting harmful environmental effects.