- Earth Systems and Resources: Earth Science Concepts and Mining
Earth’s structure: core (iron, nickel, generates Earth’s magnetic field), mantle (oxygen, silicon, magnesium) asthenosphere (upper mantle, contains magma), lithosphere (very upper mantle and crust, tectonic plates), crust (continental and oceanic)
Plate tectonics: convection currents in asthenosphere move plates, divergent, convergent and transform boundaries, subduction zone, faults
Rocks and minerals: rocks are solid aggregates of one or more minerals, mechanical vs. chemical weathering, rock cycle (process of rock formation, weathering, and lithification), igneous, sedimentary, and metamorphic rock
Geologic hazards: volcanoes occur at convergent or divergent plate boundaries or hot spots, they emit lava, ash and gas (H2O, CO2, N2, CO, SO2, H2S), can cause cooler regional temps (volcanic dust) and global cooling (sulfur haze), earthquakes occur along fault lines, underwater they cause a tsunami, ring of fire in Pacific Ocean is very geologically active
Mining: removal of land surface to get the mineral desired, causes habitat loss for wildlife and deforestation and induces erosion, may also increase air pollution (SO2 and particulates), and water pollution (eroded sediments, sulfuric acid- acid mine drainage), types of mines include placer, open pit, strip, mountaintop removal and subsurface, General Mining Law (1872), Surface Mining Control and Reclamation Act (SMCRA, 1977) requires mines to be returned to their original topography and be replanted, one subsurface mine in China has been on fire for 400 years, smelting is the heating of an ore to extract the desired metal (releases large amt. of air pollution, Ducktown, TN entire ecosystem was ruined due to acid deposition of SO2 from smelting of copper), heap leach extraction, recycling metals helps conserve geological resources
Questions:
- The most prevalent element in the Earth’s crust is
a. nitrogen b. potassium c. sulfur d. hydrogen e. oxygen
- The most prevalent element in the Earth’s core is
a. lead b. nickel c. mercury d. iron e. uranium
- The most common rock on the Earth is
a. sedimentary b. igneous c. metamorphic d. limestone e. marble
- Which of the following is not a metamorphic rock?
a. schist b. marble c. limestone d. anthracite e. slate
- Which of the following is an example of chemical weathering?
a. a rock fractured by the freezing of water in the cracks of the rock b. a rock in the desert expands when heated during the day then contracts at night, which breaks off pieces of rock c. rushing water smoothes rocks in a streambed d. rocks in a glacier scrape the underlying bedrock, causing fractures e. a rock loses particles upon exposure to rain, which dissolves portions of the rock
- Which of the following statements is true regarding volcanic eruptions?
a. lava is always emitted b. water vapor makes up the greatest proportion of gases c. most people killed during an eruption is from the lava flow d. no volcanoes have erupted in the US since 1920 e. volcanic eruptions contribute to global warming
- All of the following are environmental impacts of mining except?
a. depletion of ore resources b. increased erosion c. deforestation d. loss of biodiversity e. acid mine drainage
- The geologic hazard that results in the most human deaths is
a. volcanoes b. earthquakes c. floods d. mass wasting e. landslides
- The San Andreas fault is found at a
a. transform boundary b. divergent boundary c. convergent boundary d. subduction zone e. oceanic ridge system
- Which of the following volcanoes does not occur at a plate boundary?
a. Mt. Pinatubo, Philippines b. Mt. St. Helens, Washington c. Kilauea, Hawaii d. Cotopaxi, Ecuador e. Mt. Etna, Italy
- Earth Systems and Resources: Atmosphere
Atmosphere: troposphere (weather), stratosphere (ozone layer blocks UV-B radiation), mesosphere, thermosphere (heated by solar and cosmic radiation, auroras), weather (daily), climate (average weather)
Sun and convection: equator receives more direct sunlight making it hotter than the poles due to tilt, uneven heating of the Earth causes warmer air to rise and cooler air to sink, creating convection cells, global air circulation patterns contribute to global water circulation patterns, Coriolis effect: Earth rotates eastward deflecting winds to the right and currents clockwise in the northern hemisphere and opposite in southern hemisphere, deep ocean currents and surface currents are connected via global ocean conveyor belt transporting heat to the poles from the equator
El Nino Southern Oscillation (ENSO): slowing of the equatorial trade winds allowing warm waters to move across the pacific to South America which stops upwelling (bringing nutrient rich waters to the surface) which decreases algal growth and causing fish to go elsewhere for food, causing problems for fishermen and wildlife, effects can be felt globally
Questions:
5. Ozone in the stratosphere protects Earth from
a. cosmic rays b. meteorites c. ultraviolet radiation d. infrared radiation e. microwaves
6. The gas not found in Earth’s early atmosphere was
a. oxygen b. hydrogen c. nitrogen d. methane e. carbon dioxide
7. Which of the following exhibits the least albedo?
a. snow b. icepack c. sand d. water e. forests
8. An El Nino will result in all of the following environmental effects except
a. increased hurricanes in the southern US b. increased death of sea lions in the Galapagos Islands
c. decreased precipitation in Australia d. increased mosquito borne disease in tropical areas
e. decreased rain in the Northwestern US
9. Which of the following weather events results in the least amount of precipitation?
a. hurricane b. typhoon c. cold front d. warm front e. monsoon
10. All of the following increase carbon dioxide emissions except
a. animal feedlots b. deforestation c. burning fossil fuels d. incineration e. combustion of biomass
- Earth Systems and Resources: Global Water Resources and Use
Hydrologic cycle: powered by sun and gravity
Surface and groundwater: 97% of water is in ocean, most of remaining freshwater is frozen in glaciers, groundwater is water stored in porous underground rock called aquifers, Ogallala Aquifer is the largest in the US under Nebraska, Kansas, and N. Texas, its water amt has decreased due to irrigation, surface water is less than 0.02% of all water (rivers, lakes, streams, etc.), wetlands and swamps serve as recharge zones, purify water, and reduce erosion, a watershed is the area of land that flows into a body of surface water
Water availability and Use: 1/6 of world pop. Lack access to adequate clean drinking water and ½ lack access to sanitation, Brazil, Canada, Russia, and the Congo have lots of water due to lots of precipitation and land, 2/3 of the worlds water is used for irrigation, in the US the most domestic water is used to flush toilets
Irrigation methods: sprinklers lose lots of water to evaporation, low energy precision methods use a center pivot sprinkler, reduces evap. due to close to ground, drip irrigation applies water directly to soil, conserving water and preventing waterlogging and soil salinization
Groundwater withdrawal problems: if water withdrawal exceeds recharge the water table can be dramatically lowered, wells may dry up, sinkholes form when limestone dries out (common in Florida), cars and houses can fall into craters, subsidence is the sinking of an area due to overdrawing groundwater (San Joaquin Valley has sunk 30 ft over the last 50 yrs), saltwater intrusion occurs near coastal areas when saltwater replaces freshwater in an aquifer (Louisiana and Texas)
Water diversion projects: move water from original site to new location, dams negatives (flooding upstream areas, destroy riparian ecosystems, expensive to build, decreased flow of nutrients downstream, interfere with spawning of anadromous fish) and positives (flood prevention below dam, provides irrigation, drinking water, hydroelectricity, and recreational benefits, Examples: Aral Sea has shrunk 75% of its size since the 1960s, the water was diverted for irrigation, the sea got very salty (evaporation) destroying a fishery, lung diseases from salt storms, anemia, thyroid and kidney diseases, infant mortality and cancer rates increased, other diversions include Mono Lake, James Bay project, High Dam on the Nile, Three Gorges Dam on the Yangtze River in China will be the worlds largest hydroelectric dam
Desalination, etc.: removing water from salty or brackish water to make freshwater, reverse osmosis, distillation, expensive, where to put the salty waste, cloud seeding w/ salt or dry ice to increase precipitation, harvesting icebergs, aquifer storage and recovery, Orange County
Water conservation: low-flow toilets (use 1.6 gallons vs. 6-8 gallons), low-flow shower heads, high efficiency washers and dishwashers, can give rebates, decrease subsidies, charge more for water, education, gray water, use native species
Questions:
1. Stream discharge is
a. the length of a river times its deepest point b. the distance the water flows from the headwater to the mouth c. the speed the river travels past a fixed point d. increased in the summer due to increased temperatures e. the volume of water the river holds at any given time
2. Materials that prevent the flow of groundwater are called
a. aquifers b. aquicludes c. wells d. limestone e. artesian
3. Removal of excess amounts of groundwater in coastal areas may result in
a. saltwater intrusion b. permeability damage c. subsidence d. aquifer recharge e. surface water depletion
4. All of the following processes involve water moving with gravity except
a. infiltration b. percolation c. precipitation d. transpitation e. runoff
5. Which of the following water diversions is correctly matched with its problem?
a. increased schistosomiasis in the Aral Sea region b. increased salinity of the Yangtzee due to Three Gorges Dam c. reduced water flow through the Everglades reducing biodiversity d. Mono Lake experiences flooding due to irrigation canal placement e. James Bay has increased salinity due to irrigation diversions
6. The greatest amount of freshwater is found in
a. groundwater b. inland seas c. lakes and ponds d. ice and snow e. rivers and streams
7. Which of the following is not an impact of dams?
a. greater flooding below the dam b. impeded breeding in anadromous fish c. reduced sediment flow downstream d. lowered DO in the water downstream e. increased salinity in estuaries fed by dammed rivers
8. Which of the following policies would be a disincentive, or “stick,” that would encourage water conservation in a municipality?
a. increased water costs to reflect shortages b. increasing the availability of reclaimed water c. providing rebates for low-flow toilets and shower heads d. providing rain barrels to catch rainwater for watering lawns e. providing a property tax break on homes that use xeriscaping
9. Sinkholes result from
a. saltwater intrusion b. raising water table c. increased evaporation of groundwater d. excessive removal of groundwater e. increased flow of surface water during the spring after snowmelt occurs
10. The greatest use in municipalities of freshwater is
a. bathing b. washing dishes c. flushing toilets d. laundry e. food preparation
- Earth Systems and Resources: Soil and Soil Dynamics