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Igneous Rocks: crystallization of magma. They include two types of igneous rocks
Intrusive or plutonic magma crystallizes at depth in the Earth: Granite
Volcanic or extrusive: magma crystallizes on the surface of the Earth: Lava
Igneous rocksVery Fast cooling (days) on the surface results in many small crystals or quenching to a glass. Obsidian, pumice
Fast cooling (days to weeks) small crystals fine grain: basalt
Slow cooling (103s of years)large crystals, course grain.
Sedimentary rock Limestone: sea
shells , CaCO3
Sandstone : seas shells and mudZion National Park
Metamorphic rocks: Sedimentary or Igneous rocks that have been squashed and /or heated
Pressure: Major Earth movements ( Earthquakes) example: Gneiss
Heat close to Igneous intrusion Ex. schist
Rock Cycle How can sedimentary
rock become igneous rock?
How can igneous rock become sedimentary rock?
Abundance of elements in earth’s crust
O Si Al Fe Ca Na K Mg
Surface mining environmental effects
Habitat destruction Soil erosion Air pollution from dust particulates Pollution (especially from sediments) Acid mine damage
Water and oxygen dissolve and react with compounds
FeS2 is oxidized H2SO4
Surface mining Strip mining, as the name describes, is a
process of removing rock and soil in strips to get to the valuable mineral ores below.
Alberta tar sands 4 barrels of water to make 1 barrel of oil
Water gets put into a slurry pit, not back into river.
Surface mining: Mountain Top Removal (MTR)
similar to the strip mining but on a much larger scale.
Open pit mine
Pit mining involves digging a large hole to gather rocks and minerals from the Earth’s crust
Tar sand pits in Alberta: Energy:Water:Pollution:Global warming
Surface mining Disrupts land
Topography: alters the watershed Soil texture: compacts soil, decrease particle size Soil microbes: reduces nutrient cycling
Pollutes surface and ground water Sedimentation: dams water ways, inhibits
development of eggs and larvae Acid drainage: Pyrite contains sulfur
FeS2 + H20 > Fe + SO + H Mine subsidence
Above ground collapses
Reclaim the land
Establish topography to prior condition Replace topsoil Seed and plant native vegetation
