Mining Chapter 16

Important Definitions Mineral: Naturally occurring, usually inorganic solid that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties Ore Minerals: Minerals that are valuable and economical to extract-can be metallic or nonmetallic Gangue Minerals: minerals that have no commercial value, but are usually collected with ore minerals and must be separated

Mineral Uses Different minerals have different uses EXAMPLES , table 2 pg. 444

Subsurface vs. Surface Mining Subsurface Mining Room-and-pillar mining: a network of “rooms” are cut into a seam and between the rooms, pillars are left to support the roof Longwall mining: A machine called a shearer moves back and forth across the face of a coal seam and a conveyor takes the coal out of the mine Solution mining: Hot water is injected into the ore and dissolves it while compressed air makes bubbles that lift the ore to the surface

Subsurface vs. Surface Mining Open-pit mining: ore is mined layer by layer downward Solar Evaporation: sea water is placed in shallow ponds and allowed to evaporate, leaving behind salt (sodium chloride) which can be harvested

Environmental Impacts of Mining Abandoned mine clean up Air and noise pollution Water contamination Wildlife displacement Erosion and sedimentation Soil degradation Subsidence: sinking regions of ground from the collapse of parts of an empty mine Underground mine fires can occur when minerals are exposed to oxygen