Oil and gas
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This article originated from the Critical Issues Program authored by the American Geosciences Institute. To learn more about AGI or the Critical Issues Program, visit http://www.americangeosciences.org/critical-issues. |
Petroleum ("oil") and natural gas form from tiny plants and algae that settled in seas or lakes millions of years ago. This organic material reacts under heat and pressure to form oil and/or gas.[1] Petroleum products include gasoline, heating oil, propane, and kerosene. Not to be confused with gasoline, natural gas is mostly methane - a clear, odorless gas. When burned, oil and gas release abundant energy as well as carbon dioxide and water.
Why do oil and gas matter?
Petroleum and natural gas are the largest energy sources for the United States. In 2013, 92% of transportation fuel came from petroleum, while 22% of electric power and 79% of non-electric commercial/residential energy came from natural gas.[2] The United States has large oil and natural gas resources. Unconventional oil and gas resources, like shale gas and tight oil, are now accessible with the combination of the techniques of horizontal drilling and hydraulic fracturing.
How does geoscience help inform decisions about oil and gas resources?

Geologists and geophysicists find rock layers that contain oil or gas, and determine how much these rock layers might produce. Engineers design methods to extract the oil and gas. Other geoscientists work to reduce the environmental impacts of oil and gas extraction.
Introductory resources
- Oil and Petroleum Explained, Energy Information Administration
- Basic information on how oil was formed, products made from crude oil, refining oil, where U.S. oil comes from, prices and outlook, and oil and the environment. Also includes specific information on gasoline, diesel fuel, propane, and heating oil.
- Natural Gas Explained, Energy Information Administration
- Basic information on how natural gas was formed, delivery and storage, where U.S. natural gas comes from, imports/exports, prices, and natural gas and the environment.
- What You Need to Know: Fossil Fuels, The National Academies
- An in-depth overview of the current role of each fossil fuel energy source in the United States, the benefits and disadvantages of each energy source, and opportunities and challenges for using that energy source in the future. (Discusses coal, oil, and natural gas.)
Frequent questions
- What types and amounts of energy are produced in each state?
- What are the major sources and users of energy in the United States?
- aHow much water does the typical hydraulically fractured well require?
- How dependent are we on foreign oil?
References
- ↑ Oil and Petroleum Explained, EIA, http://www.eia.gov/energyexplained/index.cfm?page=oil_home
- ↑ What are the major sources and users of energy in the United States?, EIA, Energy in Brief, http://www.eia.gov/energy_in_brief/article/major_energy_sources_and_users.cfm
See also
- Oil and Gas Basics, American Geosciences Institute
- Coal
- Geothermal
- Hydraulic fracturing
- Nuclear energy
- Renewable energy