This is a present-day
image of Reykjavic
Iceland, where 95% of
the buildings are now
heated with geothermal
energy.
This is Reykjavic
Iceland in 1932,
when they burned
imported fossil
fuels to heat their
homes.
In this lesson, you will understand
the formation, history of use and
environmental-economic impact of
using fossil fuels.
Including:
• Coal
• Oil
• Natural Gas
Coal
is a rock consisting almost entirely of organic material. Coal
consists of fragments of land plant material, including wood, cuticle
(the waxy surface found on some leaves), sap (amber), spores and
pollen. Each of these can be present in varying degrees of
degradation due to decay near the surface and "cooking" due to
burial in thick sediments.
Petroleum
or crude oil is a naturally occurring, flammable liquid
consisting of a complex mixture of hydrocarbons of
various molecular weights, and other organic compounds,
that is found in geologic formations beneath the Earth's
surface.
Natural Gas
is a gas consisting primarily of methane. It is found
associated with other fossil fuels, in coal beds, and is
created by methanogenic organisms in marshes, bogs,
and landfills. It is an important fuel source, and the
cleanest burning of the three fossil fuels.
Coal is one of our fossil fuels because it was formed
from the remains of terrestrial vegetation that grew
as long as 400 million years ago.
• Most of our coal was formed about 300 million years ago during the
Carboniferous Period, when much of the Earth was covered by steamy
swamps. As plants and trees died, their remains sank to the bottom of the
swampy areas, accumulating layer upon layer and eventually forming a
soggy, dense material called peat.
Coal
America has more coal resources and reserves
than any other fossil fuel.
• It is burned in power
plants to produce more
than half of the electricity
we use in the United
States
• Even though you may
never see it, you each use
several tons of it every
year
Containing 25% of the World’s coal means the
US is the “Saudi Arabia” of coal.
Four Types of Coal Mined Today in
the US
•
•
•
•
•
Plant materials buried under
Peat sediments decay to form
peat, a compressed mass of
plant remains.
Compaction forces water
Lignite out of the sediments to
form lignite, a soft, brown
coal.
Subbituminous A stage between
lignite and bituminous
Further compression and
aging turn lignite into
Bituminous bituminous coal, a soft,
black coal.
Heat and pressure
metamorphose bituminous
coal to anthracite, a hard
Anthracite coal that is almost pure
carbon.
History of Coal Use
• Human use of coal dates back over 70,000
years BP! BEFORE PRESENT
Mousterian site of Les Canalettes,
France (to 73,500 years BP), where
the structure of some of the coal
recovered by archaeologists
suggests Neanderthals exploited a
local outcrop of coal.
• Industrialization brought
about an escalation in the need
for the energy contained in
coal, and now we collect it in
two ways:
• Surface mining
• Underground mining
Oil and gas formed in our geologic history during a
similar time as coal… from 400 million ybp to 150
million ybp.
During this time the seas were rich in microscopic and macroscopic
zooplankton and phytoplankton (NOT DINOSAURS!!!)
When these died they slowly sank to the bottom forming thick
layers of organic material. This in turn became covered in
layers of mud that trapped the organic material, which over
time became compressed and decomposed into oil and natural
gas.
History of Oil Use in the US
• Oil use goes back 150 years
• Our oil fields are some of the
oldest still producing in the world
• We have used approximately 175
billion barrels of oil in that time
• There are still an estimated
350 billion barrels left
• Probably billions more in fields yet
to be discovered
Where is the world’s oil supply?
Oil Uses
• Oil keeps America moving
Gasoline, Diesel fuel, aviation fuel
• Used to keep homes and
businesses warm
• Used to produce lubricants
• Used to make plastics
• Used to make fertilizers
While coal is the most
abundant fossil fuel, oil is
the most used in the US.
Oil supplies 40% of all
energy this country
consumes.
1. Of what gas is Natural Gas primarily composed?
2. Which of the fossil fuels is the cleanest burning?
3. What is a pre-cursor to coal?
4. Who were the first humans to use coal?
5. What ways are coal mined today?
6. How is the formation of oil and natural gas different from
coal?
7. Which fossil fuel is the most abundant in the U.S.?
8. Which fossil fuel is the most used in the U.S.?
Crude Petroleum must be refined
•from oil rigs
• Then to pipeline
• Then to the refinery
Nearly 75% of refined oil goes
towards transportation!
What is an oil reservoir?
Think about the aquifer which transfers water
freely to above the ground. Instead of water…
•Tiny droplets of oil are trapped inside
porous rocks, like sandstone, limestone, and
shale.
These pores
can only be
seen with a
microscope
This porous, oil-rich layer is under tremendous
pressure, because of the cap rock above it. Once
tapped into, it flows freely to the surface.
Oil
Technology and Production
Drilling wells:
• Small drilling rig to dig starter hole
• Larger rig to dig nearly to reserve
Once reserve is reached:
• Gushers
• Blowout preventers
Types of Production
• Primary
 Grasshoppers
 Christmas tree
• Secondary
 Waterflooding
• Problems: Very expensive, environmentally damaging, and only recovers
only 1/5 of oil
9. What process changes crude oil into useful products?
10. What does the majority of refined oil go towards in the
U.S.?
11. Describe an oil reservoir.
12. What type of rock typically traps oil droplets?
13. What two types of oil production are there?
14. Why is primary recovery cheaper than secondary recovery?
15. Describe waterflooding, and tell why it is so
environmentally unfriendly.
Natural Gas
• Considered worthless for many years, and simply
burned off during primary oil production.
• Colorless, shapeless, and
odorless
• Methane is the chief
chemical component of
natural gas
•It is highly flammable
• burns completely
• produces no ash
• very little air pollution (cleanest
burning fossil fuel)
Use of Natural Gas
Oil Deposits
• Only 1/5 of energy
used in US is natural
gas.
• Mostly used in homes
for heating, and cooking
Gas companies add a
chemical called butyl
mercaptan to make it
smell.
What do you notice about the placement of
natural gas resources in the United States?
History of NG
• No record of collection or use until 1821
•Used exclusively in street lamps until
electricity was harnessed.
• Robert Bunsen
• Welding after WWII,
pipes manufacturing
Why Use Natural Gas?
Acids—hydrochloric acid (usually 28%-5%), or acetic
acid is used in the pre-fracturing stage for cleaning the
perforations and initiating fissure in the near-wellbore
rock.
Sodium chloride (salt)—delays breakdown of the gel
polymer chains.
Polyacrylamide and other friction reducers—minimizes
the friction between fluid and pipe, thus allowing the
pumps to pump at a higher rate without having greater
pressure on the surface. Polyacrylamide are good
suspension agents ensuring the proppant does not fall
out.
Ethylene glycol—prevents formation of scale deposits
in the pipe.
Borate salts —used for maintaining fluid viscosity
• Easy flows naturally
due to pressure:
during the temperature
increase.
Sodium
and
carbonates
Christmas tree
(used
topotassium
regulate
flow) —used for
maintaining effectiveness of crosslinkers.
Glutaraldehyde—used
• Difficult must
be pumped viaas disinfectant of the water
(bacteria elimination.)
horsehead pump
Guaror
gum and other water-soluble gelling agents—
•Hydraulic fracturing
increases viscosity of the fracturing fluid to deliver more
First used in 1947, it wasn’t
until 1998
modern
technology
efficiently
the that
proppant
into
the formation.
made possible the economical extraction of shale gas. It was first
Citric acid—used for corrosion prevention.
used in the Barnett Shale in Texas. The energy from the injection
Isopropanol
—increases
the viscosity
of the fracture
of a highly pressurized hydraulic
fracturing
fluid creates
new
fluid.
channels in the rock, which
can increase the extraction rates and
• Plentiful
• Easy to pipe from one location
to another
• Clean burning
Easy and Difficult Gas
ultimate recovery of natural gas.
From Ground to Home
• Pipeline
• Storage facility
• Smaller pipe
network
• Homes and
businesses
Ease of
production and
movement make
NG an economical
choice
15. Why is natural gas so clean-burning?
16. How do natural gas companies help ensure
the safety of its use?
17. Describe hydraulic fracturing, and how it
can be used to increase natural gas production.
18. How is secondary recovery of natural gas
an environmental threat?
19. Why is natural gas use economically
advantageous as compared to coal or oil?
Supply and demand dictates
that as hydrocarbon supplies
diminish, prices will rise.
Higher prices will, in turn,
lead to a market for
alternative renewable energy,
and increased consumption of
those resources.
Renewable energy resources have not been
economical to exploit, but will become
economical as fossil fuel supplies dwindle.
Artificial gasolines (called
synfuels) and other
renewable energy sources
currently require more
expensive production and
processing technologies than
conventional petroleum
reserves, but may become
economically viable in the
near future.
The widescale use of fossil
fuels, (coal at first and
petroleum later), to fire
steam engines enabled the
Industrial Revolution.
• Combustion of fossil fuels
1908
1969
generates sulfuric, carbonic, and
nitric acids, which combine with
water and fall to Earth as acid rain,
impacting both natural areas and the
artificial human-generated
environment.
• Monuments and sculptures made
from marble and limestone are
particularly vulnerable, as the acids
dissolve calcium carbonate.
• Fossil fuels also contain radioactive
materials, mainly uranium and
thorium, which may be released into
the atmosphere when combusted.
Harvesting, processing, and distributing
fossil fuels can also create environmental
concerns.
• Coal mining methods, particularly
mountaintop removal and strip mining,
have negative environmental impacts
• Offshore oil drilling poses a hazard to
aquatic organisms.
• Oil refineries also have negative
environmental impacts, including air and
water pollution.
Transportation of coal requires the use of diesel-powered
locomotives, while crude oil is typically transported by tanker
ships, each of which requires the combustion of additional
fossil fuels.
20. What types of acids are created, when hydrocarbons are
combusted, later leading to acid rain production?
21. What is the average pH of rainwater in the DFW area?
22. What radioactive elements may be released during the
large-scale combustion of fossil fuels?
23.What fossil fuel harvesting methods are the most
environmentally unfriendly?
24. What fossil fuel production methods are the most
environmentally unfriendly?
25. Describe two ways the transport of oil is detrimental to
the environment.