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Earth Systems 3209. Reference: Chapters 21; Appendix A & B. Unit: 5 Earth’s Resources. Unit 5: Topic 2.1. Types of Mines. Focus on . . . i dentifying the different types of mining. evaluating the advantages and disadvantages associated with each type of mining. Types of Mines.
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Earth Systems 3209 Reference: Chapters 21; Appendix A & B Unit: 5Earth’s Resources
Unit 5: Topic 2.1 Types of Mines Focus on . . . • identifying the different types of mining. • evaluating the advantages and disadvantages associated with each type of mining.
Types of Mines 1) Open Pit Mine 2) Underground
Types of Mines • Open Pit Mining • Surface mining in which huge portions of Earth are dug from the surface to extract the desired mineral within them, resulting in a large pit. • Open pit mines are usually accessed by surface terracing, thereby allowing technological equipment to follow the shape of the deposit. • Open-pit mines are used when deposits of commercially useful minerals or rocks are found near the surface. • As a result, the potential exists for considerable destruction to both surface soil and vegetation, and the release of significant amounts of mine dust.
Types of Mines 1) Open Pit Mining
Impacts of Open Pit Mines • Clearing: First the bulldozing and preparation kills all existing floral and fauna species on the site. • Mining: Open-pit mining is known for its large amount of dust production. Also the noise created. • Chemical and Toxic Pollution: The chemicals and toxins released seep into nearby water supplies and pollute it. • Soil Degradation: Strong acidic or alkaline deposits begin to seep into the surrounding soil making them useless in terms of growth. • Exposure: The exposure to weathering erodes the soil much quicker. Some soils endure mass compaction. • Scree: Mining operations in mountain sides start to cut into the Earth creating a scree drop effect.
Pros/Cons of Open Pit Mines • Open-pit mining in relation to underground mining experience lower costs, greater safety, and mechanically easier operations. • Surface mining is more efficient than underground mining in terms of recovery, grade control, economy, and flexibility of operation. • However, many deposits, are too small or irregular, and/or deeply buried to be extracted efficiently by surface mining methods and the mine must be converted to underground operations or abandoned.
Types of Mines • 2) Underground Mining • Underground mining is done when the rocks, minerals, or gemstones are too far underground and can not be extracted economically by surface mining or if the shape of the ore body is better suited for underground mining. • Some undergroundmining techniquesinclude: • Drift Mining, • Slope Mining, • Shaft Mining.
Types of Mines • 2) Underground Mining • Accessing underground ore can be achieved via a decline (ramp), inclined vertical shaft or adit. • Levels are excavated horizontally off the decline or shaft to access the ore body. Slopes are then excavated perpendicular (or near perpendicular) to the level into the ore.
Example 1: Which type of mining process involves excavating large areas of land resulting in high levels of environmental damage? (A) open pit (B) room and pillar (C) underground (D) shaft mines
Example 2: Which is the true statement regarding underground mining operations? A) they are cheaper to operate because of low-cost equipment B) they cause less environmental surface damage when compared to open pit mines C) they cause more dust and noise at the surface than open pit operations D) the ore is more costly to process that ore from an open pit mine
Your Turn . . . Take the time and complete the following questions . . .(Solutions to follow) Questions: What are two disadvantages of open-pit mines?
Solutions . . . Answer:May include any two of the following: • Clearing: First the bulldozing and preparation kills all existing floral and fauna species on the site. • Mining: Open-pit mining is infamous for its large amount of dust production. Also the noise created. • Chemical and Toxic Pollution: The chemicals and toxins released seep into nearby water supplies and pollute it. • Soil Degradation: Strong acidic or alkaline deposits begin to seep into the surrounding soil making them useless in terms of growth. • Exposure: The exposure to weathering erodes the soil much quicker. Some soils endure mass compaction. • Scree: Mining operations in mountain sides start to cut into the Earth creating a scree drop effect.
Summary . . . Overview of Points covered: Two types of Mining: Open Pit Mining Underground Mining • Pros and Cons of the two types of mining: • Open-pit mining in relation to underground mining are lower costs, greater safety, and mechanically easier operations. • Surface mining is more efficient than underground mining in terms of recovery, grade control, economy, and flexibility of operation. • However, many deposits, are too small or irregular, and/or deeply buried to be extracted efficiently by surface mining methods and the mine must be converted to underground operations or abandoned.
