1. Formation and Distribution
Fossil Fuels
Formation and Distribution

2. Fossil Fuels
Coal
Oil (Petroleum)
Natural Gas

3. Formation of Fossil Fuels – common conditions
High Organic Production
Burial of organic material
Reducing conditions – little or no free oxygen
Reducing conditions preserve organic matter
Coal and Petroleum diverge from here

4. Formation of Coal Accumulation of land plant material
Reducing conditions – coastal and inland swamps

5. Formation of Coal
Organic accumulation is greater than destruction (because of reducing conditions)
Organic matter builds up to form peat

6. Formation of Coal Peat is compressed to form lignite – brown coal
Lignite is compressed and volatile compounds are lost to form bituminous coal – soft coal
Bituminous coal is further compressed and heated to form anthracite – hard coal

7. Formation of Petroleum and Natural Gas
Accumulation of organic material – typically marine mud
Burial and preservation of organic material – reducing conditions
Reducing conditions in deep sea or on continental shelves during times of unusual oceanic circulation

8. Formation of Petroleum and Natural Gas
Black, organic-rich mud is buried deeper and converted to rock – shale
With burial, the organic matter is heated
When heat is sufficient (but not too great) – in the range of degrees C – the organic matter is “cooked” and oil forms
Process is called thermal maturation

9. Formation of Petroleum and Natural Gas
If heat is greater than 300 degrees C, the liquid petroleum is further broken down to form natural gas
If heat is too great, even the natural gas is broken down to form carbon dioxide, which has no value as a fuel

10. Migration and Concentration
Petroleum must leave source rock
Process is called migration
Migration is essential because most source rocks are too fine-grained to enable easy extraction of the oil
To be economically concentrated, petroleum must migrate to a reservoir rock with a trap

11. Examples of Petroleum Traps

12. Petroleum Resources Conditions for source rock are rare
Conditions for maturation must be just right
Migration must not let petroleum escape to surface
Reservoir rock must be present
Trap must exist before migration occurs

13. Where did the U.S. Petroleum Industry begin?
Right here in New York!
First gas well – Fredonia, New York

14. Distribution of Petroleum
Economic accumulations of petroleum only occur when all of these conditions are met
These conditions and the sequence of occurrence do not occur everywhere
Conditions are most likely where there are thick accumulations of sedimentary rock – in sedimentary basins

15. Some of the world’s most productive sedimentary basins
Saudi Arabia
Kuwait
Alaska – north slope
Texas – Louisiana Gulf Coast
Iraq and Iran
Mexico
Venezuela

16. Refining of Petroleum Heat and/or chemical treatment to produce:
Gasoline
Diesel Fuel
Kerosene
Liquified Propane (LPG)
Petroleum bases for plastics