Geologic Resources

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Geologic Resources
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Renewable vs. nonrenewable

• Renewable
• Energy source that replenishes on a time scale
  short enough to be usable again
• Trees, wind power, falling water for
  hydroelectric power, work of animals
• Non-renewable (e.g. fossil fuels)
• Energy source that is replenished much slower
  than it can be produced
• Oil, coal, natural gas millions of years

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Industrialization

• Demand for energy beyond the
  supply of traditional
  renewable resources
• Devices which produced energy much
  faster than from renewable sources
• Efficient ways of extracting
  nonrenewables
• Feedback!!

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The Numbers

• Btu amount of energy necessary to raise T of 1
  lb of water by 1F
• 2004 US consumed 100 quadrillion Btu (quads)
• Compared to global average of 440 quads
• Each American consumes
• 4.5x the global average
• energy consumption/person

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Reserves vs. Resources

• Reserve
• Deposits that have already been mined
  economically and legally at present
• Resource
• The entire amount of a given material that may
  become available for use
• Often too poor quality to mine but may be useable
  as technology advances

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Resources An educated guess
? 480 yrs
? 135 yrs
? 36 yrs
? 35 yrs
? 29.6 yrs
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Oil and Natural Gas
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How do oil and gas form?

• In areas where more organic matter is produced
  than destroyed
• Areas where O2 supply is insufficient to decay
• Areas where sedimentation organics is high
• Well-lit coastal seawater or tropical lagoon
  teeming with abundant microscopic organisms

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How long does it take?

• Millions of years of burial
• Chemical reactions triggered by elevated T
• Transform organics into hydrogen and carbon
• The oil window
• Depths about 2-5 km (2.3 km oil, 4.6 km gas)
• Shallow depths too cool to produce crude oil
• Deeper depths too hot, broken down into CH4

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How do we get oil reservoirs?

• Sediments compact and force oil into pore spaces
  of nearby rock
• Low density of these oils causes them to rise to
  the highest place they can reach where they float
  atop the water
• Need some geologic formation that traps the oil
  (so it doesnt escape)

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Oil in Texas
Henderson in Rusk County, stratigraphic trap
Fault blocks formed 360-245 mya, filled by reefs,
marine lakes later ? salt
Salt domes near Beaumont
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Oil Production and Consumption

• In 2004, 30 billion barrels were pumped out
• Increase of 3.4 for the previous year
• US produced 2.6 billion barrels more than any
  country except Saudi Arabia
• But it consumed 7.5 billion barrels one-quarter
  of the world total
• Gap in US between production and consumption is
  growing at 5 per year
• At current rates of consumption, US will be
  importing all of its oil by 2020

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Will we run out of oil?

• Worldwide reserves at current estimates, will be
  depleted within 40 years
• Resources gtgt reserves
• But before this, price of oil will rise so high
  it will be unusable for burning anymore

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Main uses of oil, natural gas

• Oil (and byproducts)

• Natural Gas

• Fuel for jets, cars
• Kerosene lanterns
• Lubricants
• Wax (to pack frozen foods)
• Asphalt
• Plastics

• Electricity generation
• Vehicles
• Hydrogen production
• Industrial production

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Problems with Oil, Natural Gas

• Oil spills
• Exxon Valdez (3/24/1989)
• 40,000/otter cleaned
• Fluctuating market costs due to war, politics
• Production of CO2 and CO

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Coal
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How does coal form?

• In a similar way to oil, except that it comes
  from swamp vegetation
• Coastal swamps that get buried with sediment
• All that sediment
• shed into the Gulf