Geo Final: Energy Resources

What type of environments favor coal formation?

Coastal Swamps turn sediment into peat.

What are tar sands?

Combination of clay, sand, water and bitumen (heavy black viscous oil) Pros: Less than 5% has been produced. Large growing potential. Cons: Low net energy return. Large amounts of water required, Habitat destruction.

What is Coal

Decomposed vegetation which turns into solid, brittle rock after a long period of time due to compression.

How does it affect oil/natural gas production for the US?

Fracking increases the production of oil and natural gas, which boosts the U.S economy.

What conditions are necessary for the formation of oil vs gas with respect to depth and temperature?

Gas: Gas survives at a higher temperature than oil, meaning it usually is found deeper within the surface. Oil needs to be about 3.5-6.5 km deep and 25 degrees C

We have warm shallow, low-oxygen oceans globally today. Why are we concerned about running out of oil/gas if we have the type of environment that favors their formation?

Hydrocarbon deposits are rarely found in rocks younger than 1-2 million years old. The formation of new fossil fuels can not occur within ones lifetime. resources are being depleted faster than they can be created.

Why is Fracking controversial?

May contaminate groundwater may cause earthquakes, pollutes atmosphere

Why is coal so widely used for energy?

Most abundant fossil fuel, cheap, relatively easy to mine

oil window

Narrow range in temperature in which oil can form. 3.5-6.5 km 50-150 degrees C

How are fossil fuels formed?

Oil and gas are hydrocarbons derived from the remains of plankton buried with clay in an organic ooze. Burial transforms ooze into source rock, a black shale containing kerogen. If the rock is subjected to appropriate temperatures, organics transform into oil and gas.

What are the major fossil fuel types?

Petrolium/Coal Oil Natural Gas

How does oil form?

Plants and animals fall to the ocean floor. Their dead bodies then are covered in sediment and rock. Over millions of years, the heat and pressure causes it to turn into oil and natural gas.

Pros and Cons of Fracking?

Pros: -Increases the production of natural gas (methane) Increase in economic activities Price for drilling for natural gas is low Cons: Water contamination by chemicals (when fracking is done) Earthquakes Major health concerns for people who live nearby drilling None renewable

What is fracking?

Pumping a mixture of sand, water and chemicals to create cracks in rock layers, which allow the natural gas to flow to the surface.

Where are most oil reserves located today?

Southwest Asia

How is coal mined?

Surface Mining and Sub Surface mining Surface: Removing soil, subsoil, and other strata and then extracting a mineral deposit found fairly close to the earth's surface SubSurface: Extraction of a metal ore or fuel resource such as coal from a deep underground deposit

What are salt domes and what is their relationship to oil reserves?

a dome-shaped structure in sedimentary rocks, formed where a large mass of salt has been forced upward. Such structures often form traps for oil or natural gas.

Natural Gas

a fossil fuel formed from the remains of tiny marine organisms that died 200-400 million years ago. the main ingredient to natural gas is methane (CH4) Pros: Large Supplies; High Energy Yield; Emits less CO2 and other pollutants than other fossil fuels. Cons: Low net energy yield for LNG; Releases CO2 and other pollutants when burned; Difficult and costly to transport from one country to another. none renewable.

How does coal form?

coal is formed from dead/decayed plants that are fossilized for millions of years and is applied heat and pressure.

Oil Shales

fine-grained sedimentary rock from which oil can be extracted; mudstone that contains organic polymers (kerogen); oil source rock that has not yet generated most of it's oil Pros: can help meet oil demand, also has other pros of oil Cons: lower net energy yield, processing requires a lot of H20, surface mining causes damage/pollution, very expensive process, non-renewable

How do porosity/permeability affect oil reserves?

the greater the porosity, the greater the capacity of a reservoir rock to hold oil. the greater the rock's permeability, the easier it is for the oil to be extracted