Earth’s Changing Environment
Lecture 7
Global and US
Fossil Fuel Resources:
Oil and Natural Gas
Fossil Fuels


Formed 50 million to
350 million years ago
from plants and animals.
Fuels
•
•
•
•
•
Petroleum
Natural Gas
Coal
Shale Oil
Tar Sands
US Energy Consumption (QBtu)


Petroleum
38 (39%)
Natural Gas 23 (24%)
Oil and Natural Gas
Oil
Hydrocarbon
chains
CH2-CH2- CH2----
2CH2 + 3O2 
2CO2 + 2H2O
Natural Gas
Primarily Methane
CH4
CH4 + 2O2 
2H2O + CO2
Oil

Crude oil is measured in
barrels. A 42-U.S. gallon
barrel of crude oil
provides slightly more
than 44 gallons of
petroleum products.
Oil Refinery
After crude oil is
removed from
the ground, it
is sent to a
refinery
The crude oil is
separated
into useable
petroleum
products.
Oil Refinery
A 42-U.S. gallon barrel of crude
oil provides slightly more than
44 gallons of petroleum
products.
One barrel of crude oil, when
refined, produces 20 gallons of
finished motor gasoline.
Petroleum Products
Gasoline Prices
Natural Gas
Natural gas prices
have fluctuated
because of variable
supply.
New pipelines from
Alaska may solve
some of this
problem.
Reserves and Resources


Reserves are known
sources that are
extractable with current
technologies at current
prices.
Resources include
sources not currently
being exploited because
of cost and sources not
yet discovered.
Oil and Gas Units


Gbo billion barrels of oil.
G stands for Giga. Used
for global and US oil
resources
TCF trillion cubic feet.
Used for global and US
natural gas resources.
Example Problem 1
US annual oil consumption equals
7.2 Gbo. Express this value in
millions of barrels per day.
US Oil consumption
= 7.2x109 bbl/ 365 days
= 20 million bbl/day
(11 million bbl day imported)
Global Oil and Gas
Reserves, Resources, Consumption

Oil
•
•
•

Reserves 1,000 Gbo
Resources 1,700 Gbo
Consumption 28 Gbo
Natural Gas
•
•
•
Reserves 5,500 TCF
Resources 10,000 TCF
Consumption 90 TCF
US Oil and Gas
Reserves, Resources, Consumption

Oil
•
•
•

Reserves
22 Gbo
Resources
98 Gbo
Consumption 7.2 Gbo
Natural Gas
•
•
•
Reserves
180 TCF
Resources
710 TCF
Consumption 23 TCF
Global Oil Resources
•
•
•
•
•
•
•
•
•
•
•
•
Saudi Arabia
Iraq
Iran
Kuwait
UAE
Russia
Venezuela
Nigeria
Libya
China
Mexico
United States
26%
11%
10%
10%
6%
5%
5%
3%
3%
3%
2%
2%
Global Oil Production
•
•
•
•
•
•
•
•
•
Saudi Arabia
United States
Russia
Iran
Mexico
Norway
China
Venezuela
Canada
12%
11%
10%
5%
5%
5%
4%
4%
4%
Global Natural Gas Resources
•
•
•
•
•
•
•
•
•
•
Russia
Iran
Qatar
Saudi Arabia
UAE
United States
Algeria
Nigeria
Venezuela
Iraq
29%
16%
13%
4%
3%
3%
3%
3%
3%
2%
Global Natural Gas Production
•
•
•
•
•
•
•
Russia
23%
United States
22%
Canada
7%
United Kingdom 4%
Algeria
3%
Netherlands
3%
Indonesia
3%
Example Problem 2
Assuming constant level of consumption, estimate
the lifetime of US oil resources
Lifetime = 98 Gbo / 7.2 Gbo/year = 14 years

Assuming constant level of consumption, estimate
the lifetime of global oil resources
Lifetime = 1700 Gbo / 28 Gbo/year = 60 years


What is wrong with these assumptions?
When will worldwide conventional oil
production peak?
US Production Peaked in 1970
Lower 48 Crude Oil Reserves & Production, 1945-2000
Crude Oil Reserves, Billion Barrels
35
Peak
Reserves
1959
4.0
Peak
Production
1970
3.5
30
3.0
25
2.5
20
2.0
15
1.5
10
5
0
1945
1950
1955
1960
1965
1970
1975
1980
Lower 48
Reserves
1.0
Lower 48
Production
0.5
1985
1990
1995
0.0
2000
Crude Oil Annual Production, Billion Barrels
40
Published Estimates of World Oil Ultimate Recovery
USGS 5% 2000
USGS Mean 2000
USGS 95% 2000
Campbell 1995
Masters 1994
Campbell 1992
Bookout 1989
Masters 1987
Martin 1984
Nehring 1982
Halbouty 1981
Meyerhoff 1979
Nehring 1978
Nelson 1977
Folinsbee 1976
Adams & Kirby 1975
Linden 1973
Moody 1972
Moody 1970
Shell 1968
Weeks 1959
MacNaughton 1953
Weeks 1948
Pratt 1942
0
0.5
Source: USGS and Colin Campbell
1
1.5
2
2.5
Trillions of Barrels
3
3.5
4
Different Interpretations of a Hypothetical 6,000 Billion Barrel
World Original Oil-in-Place Resource Base
6,000
5,000
4,200
Billion
Unrecovered
3,000
Billion
Unrecovered
Unrecoverable
Reserves
Growth
Undiscovered
4,000
3,000
Reserves Growth
Adds 10%
2,000
50%
Recovery
Factor with
Reserves
Growth
40%
Recovery
Factor
Without
Reserves
Growth
1,000
Proved
Reserves
Cumulative
Production
30%
Recovery
Factor
0
USGS Approach
1995 Campbell/Laherrere Approach
Campbell-Laherrère World Oil
Production Estimates, 1930-2050
Production Peak
2004
Campbell
Annual Production Scenarios with 2 Percent Growth Rates and
Different Decline Methods
60
USGS Estimates of Ultimate Recovery
History
2037
Billion Barrels per Year
50
40
Ultimate Recovery
Probability
BBls
---------------------------Low (95 %)
2,248
Mean (expected value)
3,003
High (5 %)
3,896
Mean w/ 2% Growth and
2% Decline
Mean w/ 2% Growth and
10 R/P Ratio Decline
2016
2% Growth
& 10 R/P Ratio Decline
30
2% Growth
& 2% Decline
20
10
0
1900
1925
1950
1975
2000
2025
2050
Note: U.S. volumes were added to the USGS foreign volumes to obtain world totals.
2075
2100
2125
Annual Production Scenarios with 2 Percent Growth Rates and
Different Resource Levels (Decline R/P = 10)
70
USGS Estimates of Ultimate Recovery
Billion Barrels per Year
60
50
40
2047
Ultimate Recovery
Probability
BBls
---------------------------Low (95 %)
2,248
Mean (expected value)
3,003
High (5 %)
3,896
2%
Growth
2037
2026
Decline
R/P = 10
30
20
10
0
1900
History
Mean
Low (95 %)
High (5 %)
1925
1950
1975
2000
2025
2050
2075
Note: U.S. volumes were added to the USGS foreign volumes to obtain world totals.
2100
2125
Annual Production Scenarios for the Mean Resource Estimate
and Different Growth Rates (Decline R/P = 10)
70
USGS Estimates of Ultimate Recovery
2030 @ 3% Growth
Billion Barrels per Year
60
50
Ultimate Recovery
Probability
BBls
---------------------------Low (95 %)
2,248
Mean (expected value)
3,003
High (5 %)
3,896
2037 @ 2% Growth
2050 @ 1% Growth
40
30
Decline
R/P = 10
20
History
10
0
1900
Mean
1925
1950
1975
2000
2025
2050
Note: U.S. volumes were added to the USGS foreign volumes to obtain world totals.
2075
2100
2125
Annual Production Scenarios for the Mean Resource Estimate
Showing Sharp and Rounded Peaks
60
Billion Barrels per Year
50
40
USGS Estimates of Ultimate Recovery
Peak in 2037
Decline @ R/P = 10
Ultimate Recovery
Probability
BBls
---------------------------Low (95 %)
2,248
Mean (expected value)
3,003
High (5 %)
3,896
30
Peak in 2030
Decline @ 5 %
2%
Growth
20
History
10
0
1900
Mean
1925
1950
1975
2000
2025
2050
Note: U.S. volumes were added to the USGS foreign volumes to obtain world totals.
2075
2100
2125
When will Global Oil Production Peak?



Difficult to predict.
Depends on
geology and
economics.
Best estimates are
sometime between
2004 and 2050.