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Distribution of Natural
Energy Resources

Explore how geological processes, climate patterns, and tectonic activity determine where fossil fuels, renewable sources, and minerals are found across the globe.

AP Environmental Science

What Are Natural Energy Resources?

Natural energy resources are materials or phenomena found in the environment that humans harness to produce usable energy. They include fossil fuels formed over millions of years, radioactive minerals, and continuously renewed sources like sunlight and wind.

Non-Renewable
Coal, oil, natural gas, uranium: finite stocks formed by geological processes over millions of years
Renewable
Solar, wind, hydroelectric, geothermal, biomass: replenished on human timescales through natural cycles

Why Distribution Matters

Energy resources are not evenly distributed across the planet. Geological history, latitude, topography, and climate create dramatic inequalities. This uneven distribution shapes geopolitics, trade networks, and environmental justice.

Geological Formation of Fossil Fuels

Sandstone (cap rock) Shale (source rock) Reservoir rock (porous) Basement rock Oil/Gas Trap Millions of years Ancient organic matter Heat + Pressure

Petroleum systems require source, migration, reservoir and seal

A layered anticline cutaway has dark source rock below a gold migration pathway and a porous fluid-bearing layer under a thick curved seal; an enlarged pore view shows grains surrounded by fluids.A petroleum system combines organic-rich source rock, migration pathways, porous reservoir rock and a trapping seal. Fluids occupy connected pore spaces within rock.

Conventional petroleum trap

Conventional petroleum trap. A petroleum system combines organic-rich source rock, migration pathways, porous reservoir rock and a trapping seal. Fluids occupy connected pore spaces within rock.A petroleum system combines organic-rich source rock, migration pathways, porous reservoir rock and a trapping seal. Fluids occupy connected pore spaces within rock.

Key Factors Controlling Distribution

1
Tectonic activity: Plate boundaries determine where geothermal energy, volcanic minerals, and fossil fuel basins form.
2
Past climate and biology: Ancient tropical seas and swamps created the organic deposits that became coal, oil, and gas.
3
Latitude and solar angle: Solar irradiance is highest near the equator, where sunlight strikes the surface most directly.
4
Topography and wind patterns: Mountain passes, coastal plains, and open grasslands concentrate wind energy potential.
5
Hydrological cycle: Precipitation and elevation drops determine hydroelectric potential in river systems.

Renewable vs. Non-Renewable

Renewable Non-Renewable
Replenishment Continuous (human timescale) Millions of years
Distribution driver Climate, latitude, topography Geological history, tectonics
Location flexibility Broadly available (varies by type) Concentrated in specific basins
Examples Solar, wind, hydro, geothermal Coal, oil, natural gas, uranium
Environmental impact Low emissions, land use concerns High emissions, habitat disruption

Global Fossil Fuel Distribution

0% 12% 24% 36% 48% Middle East N. America Russia/CIS Asia Pacific Africa Oil Natural Gas Coal

Solar Energy Distribution

\(\text{kWh/m}^2\text{/yr}\)
0 800 1600 2400 90°N 45°N 0° 45°S 90°S Peak Zone

Wind and Hydroelectric Potential

Wind Energy
Strongest in coastal areas, mountain passes, and open plains. Trade wind zones (30°N/S) and mid-latitude westerlies (40-60°N/S) are prime locations. Power scales with the cube of wind speed.
Hydroelectric
Requires high precipitation and elevation drop. Concentrated in mountainous, wet regions: Pacific Northwest, Scandinavia, Himalayas, Andes, Congo Basin. River flow must be consistent year-round.

Wind lifts a blade and the nacelle reveals the conversion chain

A three-bladed wind turbine on a tower exposes its horizontal shaft, generator ring, bearings and electrical equipment in a nacelle cutaway.A 50 m rotor radius sweeps 7,854 m². At air density 1.225 kg/m³ and wind speed 8 m/s, available kinetic power is 2.463 MW; an assumed 40% overall efficiency gives 0.985 MW of electricity at that operating point.

Available and electrical wind power

Available and electrical wind power. A 50 m rotor radius sweeps 7,854 m². At air density 1.225 kg/m³ and wind speed 8 m/s, available kinetic power is 2.463 MW; an assumed 40% overall efficiency gives 0.985 MW of electricity at that operating point.A 50 m rotor radius sweeps 7,854 m². At air density 1.225 kg/m³ and wind speed 8 m/s, available kinetic power is 2.463 MW; an assumed 40% overall efficiency gives 0.985 MW of electricity at that operating point.

Geothermal Energy and Tectonics

Mantle (hot rock) Earth's Crust Plate Boundary Heat flow Plant Iceland Ring of Fire

How to Analyze Resource Distribution

1
Identify the resource type: Is it renewable (driven by climate/geography) or non-renewable (driven by geological history)?
2
Examine the controlling factor: Latitude for solar, tectonics for geothermal, sedimentary basins for oil/gas, elevation + rainfall for hydro.
3
Evaluate concentration vs. dispersion: Is the resource found in a few specific regions (oil) or broadly available (solar)?
4
Consider access and infrastructure: Can the resource be extracted and transported economically? Technology and politics both matter.
5
Assess environmental trade-offs: What are the ecological costs of extraction, and how do they vary by location?

Example 1: Why Is Oil in the Middle East?

During the Mesozoic Era (252-66 million years ago), the Middle East was covered by a shallow tropical sea: the Tethys Sea. Massive marine organism die-offs created thick layers of organic-rich sediment. Burial and tectonic compression transformed this material into petroleum trapped under salt domes and anticlines.

Source
Ancient Tethys Sea organisms deposited organic-rich shale
Heat + Pressure
Burial converted kerogen into liquid petroleum over millions of years
Trap
Anticlines and salt domes created impermeable seals holding oil in porous rock

Example 2: Solar vs. Wind Siting

A country at 55°N latitude with strong coastal westerlies and frequent cloud cover needs to choose between investing in solar farms or offshore wind. Which resource better matches its geography?

Solar Wind
Latitude factor Low angle, short winter days Strong mid-latitude westerlies
Cloud cover Reduces output significantly Wind unaffected by clouds
Coastal advantage Minimal Offshore wind farms ideal
Verdict Poor match Strong match

Example 3: Energy Density Comparison

Energy density determines how much land or material is needed to produce a given amount of power. This affects which resources are practical in land-scarce vs. land-abundant regions.

Power Density (\(\text{W/m}^2\))
Natural Gas ~1,000 Nuclear ~240 Solar 5-20 Wind 1-2 Biomass ~0.5 Logarithmic differences: fossil fuels are 100-1000x denser than renewables

Common Mistakes

✕ "Renewable means available everywhere equally"
Solar irradiance, wind speed, and hydro potential vary dramatically by latitude, topography, and climate. Renewable ≠ uniformly distributed.
✕ Confusing reserves with production
A country may have large reserves but low production due to lack of infrastructure or political instability. Venezuela has vast oil reserves but limited output.
✕ Ignoring geological timescales
Students often forget that fossil fuel distribution reflects conditions millions of years ago, not the current climate or geography of a region.

Summary: Energy Resources at a Glance

Resource Distribution Driver Key Regions
Oil Sedimentary basins, ancient seas Middle East, Russia, N. America
Coal Ancient swamp forests China, U.S., India, Australia
Natural Gas Sedimentary basins, shale deposits Russia, Qatar, U.S., Iran
Solar Latitude, cloud cover, aridity Sahara, Arabia, Outback, SW U.S.
Wind Pressure gradients, coastlines N. Europe, Great Plains, Patagonia
Hydro Precipitation + elevation Brazil, Canada, Norway, China
Geothermal Plate boundaries, hotspots Iceland, Philippines, U.S. West

Question 1 of 5

Which geological factor best explains why the Middle East has the largest proven oil reserves?

Question 2 of 5

A country at 60°N latitude with strong prevailing westerlies and persistent cloud cover would find the greatest energy potential in which resource?

Question 3 of 5

Geothermal energy is most concentrated in regions that are:

Question 4 of 5

Which statement about power density of energy resources is most accurate?

Question 5 of 5

Brazil generates over 60% of its electricity from hydroelectric dams. Which combination of geographic factors best explains this?