Figure 1.5

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Environmental Physics

Chapter 7:

Fossil Fuels

Copyright © 2008 by DBS


Nearly 90% of all energy is derived from fossil fuels

Nonrenewable energy source

Oil is in the shortest supply

Dependence on oil is a problem!

Figure 1.5:

Energy consumption by source for the world and for the United States: 2003.


US domestic energy production is dominated by coal

Energy production is linked directly to economic growth

Resource Terminology

Amount of resource remaining (unused or undiscovered) is difficult to predict

Predictions are based on incomplete exploration

Economic and technical factors affect the ability to extract the resource

Resource Terminology

McKelvey diagram

Figure 7.1:

The McKelvey
diagram for categorizing
reserves and resources
relates the variables of
geological certainty and
economic feasibility.

Upper left =


well known through
geologic exploration,
recoverable at current prices
with current technology


Known to exist but
expensive to extract

Resource Terminology

Economic /uneconomic and known/undiscovered dividing line changes with time


Resource Terminology


Proven reserves

reasonably certain of production using current technology

Indicated reserves

believed recoverable using improved technology

Inferred reserves

expected deposits not yet measured





Resource Terminology

Size of reserves is established by the energy industry

Old reserves exhausted

new reserves found

Except! Domestic oil…

Figure 7.2

U.S. crude oil reserves. Above the line are annual additions to reserves (the 1970
peak is Alaskan oil), and below the line is annual production. Note that the addition of reserves is
less than our production.

Resource Terminology

How do we estimate reserves?

1.) Quantitatively:

No. of barrels of oil contained in a unit volume of geological structure is a fixed amount

Total volume of geological structure x barrels per uni t volume = total reserve

2.) ‘Behavioristic approach’:

History of oil production is extrapolated

into the future to estimate the amount left

e.g. Hubbert forecast of 1969

Historical use begins with continuous

increase, reaching a maximum and

tailing off as easy deposits are

exhausted and prices rise

Figure 7.3:

Hubbert oil
depletion curve for world oil production. The
solid line shows actual production, using updated DOE data.

By 2050 oil production will
be at 10% of present level

Resource Terminology

Resource analysts do not like the behaviorist approach

Question should be answered with hard geological data

Does not take into account new technology available for extraction or discovery of new resources

Just estimates!

Resource Terminology

Map Description

This map identifies the ratio of domestic oil reserves to the domestic rate of production (R/P), in years,
for individual countries, as well as some regional totals. Note that nearly all countries (assuming no
importation of oil) are expected to deplete their usable supply or “run dry” of oil before 2100.


World appetite for oil continues to grow…

Figure 7.4:

World petroleum consumption, 1960

2003. The Organization for Economic
Cooperation and Development (OECD) countries include the United States, Japan, Western
Europe and Canada.



Of which
USA used


Hubbert’s Peak (1956)

BBLS = barrels


ULTIMATE = cumulative production plus future production


DeGolyer and



US Oil Production



US consumes more oil than any other country

Produces more oil than any other country except
Saudi Arabia and Russia)

US uses ¼ of the world's oil but has less than 2 % of
the world's known oil reserves, will last only a few
more years (depending on new discoveries)

Figure 7.5:

World oil reserves and oil use by country, 2003.

Table 7
2a, p. 212


Prior to 1989 and the collapse of communism, the former USSR had the 3

largest oil reserves in
the world

New republics have a share in the oil resources

use them to develop economically

e.g. Kazakhstan, largest discovery of oil in last 25 yrs

Presents issue due to ethnic tensions, Russia’s claim to oil rights and existing pipelines for export

Route through
russia to Black Sea

Bottle neck at

Route through Iran
to Persian Gulf


Route through
Azerbaijan to Turkey
moves 1 MBPD


First commercial oil well…1859

Figure 7.6:

The world’s first commercial oil well, Titusville, Pennsylvania, 1859. Colonel
Edwin Drake

(in top hat)
, conceived the idea of drilling for oil and used the primitive rig
pictured in the background.

69 feet,


Use of oil grew rapidly after 1859 because it could be used as a substitute for expensive whale oil

Oil is now crucial to the world’s economy

Substitution is difficult

transportation, agriculture, petrochemicals

Figure 7.7

U.S. oil consumption by end use, 2003.


Petroleum or crude oil is a mixture

oil, natural gas, asphaltic semi

All petroleum deposits contain gas but not all gas deposits contain oil

Complex mixture of hydrocarbons of various molecular weights plus other organics

Composition varies widely



conversion of crude into useful products

Fractional distillation

separation according to btp.

Passed through fractionating tower (40 m high)

Products condense and are collected (heaviest at bottom, lightest at top)

Figure 7.8:

At the refinery, the petroleum fractions are separated thermally in the fractionating
tower, then individually treated to produce the products listed.


Originates from the decay of organic material buried over millions of years under high pressures
and temperatures

Oil and gas migrates through rocks and accumulates in deposits

Found in porous/permeable reservoir rocks (sandstone, limestone and shale) surrounded by
nonporous rock

Figure 7.9:

Typical petroleum trap. The upper boundary of the trap is an impermeable layer of
rock called a roof or caprock.


Well drilled into a reservoir will produce results by natural flow

To increase and sustain removal a pump may be used

Secondary recovery involves using water to provide increased pressure

Tertiary methods are needed to extract more than the initial 35 % (steam, N
, CO

anywhere between 10
30 %

Fig. 7
10b, p. 217

Figure 7.10:

Enhanced oil recovery



largest oil field in US discovered on Alaska’s North slope (Prudhole Bay)

20 x10


Difficult to move oil tankers from Atlantic ocean through NW passage


Alaska pipeline to nearest ice
free sea port

Production is decreasing

Look to Arctic National Wildlife Reserve’s 1002 area (ANWR)

Oil Spills


Exxon Valdez largest spill in US

March 24 1989

S. coast Alaska, 11 million gallons of oil

Killed hundreds of thousands of birds/damaged local fishing industry

$45M spent on wildlife rescue and rehabilitation

Cleanup completed in 1992


Persian Gulf War

250 million gallons

Oil wells set deliberately ablaze

A pool of saffron
colored oil paints swirls along Alaska's shoreline following the Exxon Valdez oil spill in
1989. Although it was not large compared to other spills, the Valdez oil spill was one of the world's most
ecologically devastating disasters, spoiling more than 1,200 miles (1,931 kilometers) of shoreline,
including three national parks, three national wildlife refuges, and one national forest.


US has drilled more wells than any other country

Wells are deeper than ever before and only 30%

of drillings is successful

Most increases to US reserves expected to come

from offshore drilling

Offshore drilling x10 more expensive than onshore

Oil and gas brought to shore through pipelines

Figure 7.11:

Offshore drilling rig
operating in the Baltimore Canyon area.



‘There must be energy down there’ cartoon

Natural Gas

Mixture of light hydrocarbons, primarily methane (CH

Natural Gas

Natural Gas

Nonassociated gas

natural gas found alone

Associated gas

found with crude oil

First US gas well was on the shore of Lake Freedonia, NY in 1821

Storage and transport

major difficulty may be liquified (LNG)

For the expansion of gas industry major pipelines were needed

>>> 1 million miles of pipe

Natural Gas

Growth of gas consumption:

1970 x4

Slowed in 1970’s

Steady at 22 tcg (trillion cubic feet)

Natural Gas

Many uses…

Good substitute for oil (cleaner burning)

Helps to reduce dependence on foreign oil

Figure 7.12

U.S. natural gas consumption by end
use sector: 2003.

Chemical feedstock
= ammonia, fertilizers,
plastics, rubber, etc.

Natural Gas

World reserves ~ 5500 tcf, what is the estimated lifetime at consumption rate of 82 tcf per year?

US production peaked in 1973 at 24 tcf

Figure 7.13

U.S. natural gas consumption by year: 1950


5500 tcf / 82 tcf/yr = 67 years

Natural Gas

Additional unexploited resources:

(1) gases trapped within coal beds

(2) Devonian shale under most of eastern USA

(3) gas in so

called ‘tight
sands) in the Rocky Mountains

All these sources are difficult to drill, require explosives or high water pressures

Natural Gas

Producing electricity from gas is preferable over coal and oil (whose primarily use is transport)

Produces almost no SO

or mercury and 1/3 of the CO

of a coal plant (dirty coal!)

Incomplete combustion yields methane (powerful GH gas)

Short construction time

Air pollution worries of
1980’s made gas
more popular than ever

Electricity Generation by Fuel 1980

(billion kilowatt hours)

Source: EIA Annual Energy Outlook 2008 With Projections to 2030


World’s most abundant fuel

US has ¼ of total reserves

Estimated it will last 210 years at

current rates

Figure 7.14:

World recoverable
reserves of coal, 2003.



~20 x 10

Btu coal vs.40 x 10

Btu oil

Can’t substitute coal for oil

Turn coal into liquid?

Increased use is constrained by

demand, not supply


Over thousands of years peat
(decomposed plant matter) is
transformed into coal

Development of coal

Lower S


Consumption of coal in the US increasing

Percentage contribution to total energy is decreasing

Due to change to cleaner burning oil and natural gas,

railroads changing from coal to diesel and electric

Use in electric utilities increased (consume 90% of all coal produced)

Figure 7.15

U.S. coal consumption by sector: 1950


The Washington Post 03/20/08


Figure 7.16

U.S. coal deposits.

Since 1940’s production shifted
west, from underground to
surface mines

Due to air pollution laws,
search for cleaner coal,
thicker seams


Coal seams vary in thickness from a few inches to hundreds of feet

60% coal produced by strip mining

ripping tops off mountains

Aerial view of a Montana strip mine.

Dragline used in strip mine to remove coal.


Synthetic oil from gas and coal

‘gasification’ and ‘liquefraction’ of coal

Produces synfuels

Technology is 200 years old, but currently not economically attractive

Oil Shale and Tar Sands

Oil shale

oil trapped in rocks

Large deposits in US > oil reserves

Requires energy input to process the shale


Fossil fuels are projected to constitute the majority of our energy supplies

Petroleum supplies 40 % of the world’s energy

Estimates of the lifetime of resources < 100 years for oil and gas

Petroleum supplies 40 % of the world’s energy

Oil and gas accumulate in reservoir rocks capped with impermeable rocks

Oil may be extracted using primary, secondary and tertiary techniques

Coal is classified according to how much carbon it contains

Coal may be mined above ground or below the surface

Oil and gas produce less pollution than coal

Coal can be converted into oil and gas by liquefraction and gasification



Fig. 7
19, p. 235

p. 235

Fig. 7
20a, p. 236

Fig. 7
20b, p. 236

Table 7
4, p. 237

Fig. 7
21, p. 238

Fig. 7
22, p. 238

Fig. 7
23, p. 239

Fig. 7
24, p. 239

Figure 7.24:

Seismic operations print
out map for oil location. Each horizontal
line represents a detector at a different distance which records pulse strength (
axis) vs. time of travel of the shock wave (

History of Solar Heating