Download How is Petroleum Formed?

Petroleum Resource Packet
Info from www.energy4me.org
Oil and natural gas together make petroleum. Petroleum, which is Latin for
“rock oil,” is a fossil fuel, meaning it was made naturally from decaying
prehistoric plant and animal remains. It is a mixture of hundreds of
different hydrocarbons molecules containing hydrogen and carbon that
exist sometimes as a liquid (crude oil) and sometimes as a vapor (natural
gas).
How is Petroleum Formed?
Oil and natural gas were formed from the remains of prehistoric plants and
animals—that’s why they’re called “fossil fuels!” Hundreds of millions of
years ago, prehistoric plant and animal remains settled into the seas along
with sand, silt and rocks. As the rocks and silt settled, layer upon layer piled
up in rivers, along coastlines and on the sea bottom trapping the organic
material. Without air, the organic layers could not rot away. Over time,
increasing pressure and temperature changed the mud, sand and silt into
rock (known as source rock) and slowly “cooked” the organic matter into
petroleum. Petroleum is held inside the rock formation, similar to how a
sponge holds water.
Over millions of years, the oil and gas that formed in the source rock deep
within the Earth moved upward through tiny, connected pore spaces in the
rocks. Some seeped out at the Earth’s surface, but most of the petroleum
hydrocarbons were trapped by nonporous rocks or other barriers. These
underground traps of oil and gas are called reservoirs. Reservoirs are not
underground “lakes” of oil; they are made up of porous and permeable
rocks that can hold significant amounts of oil and gas within their pore
spaces. Some reservoirs are hundreds of feet below the surface, while
others are thousands of feet underground.
How Do We Get to the Oil?
The oil and natural gas we use today have been trapped deep inside the
Earth for millions of years. Although it is tempting to think of oil and gas
reservoirs as large pools and wells with giant straws that suck the fluid to
the surface, oil and gas is actually locked inside the rocks like water in a
sponge. Just like the small holes in a sponge that collect and hold water,
there are tiny spaces or pores in rocks that fill with oil and gas. For the past
100 years, oil and gas was extracted from rocks with small pores that were
still big enough that the fluids flowed easily. If you were a tiny molecule of
oil, flowing through these rocks would be like driving on a highway in the
express lane. During this time period, geologists and engineers knew about
other large quantities of hydrocarbons trapped in rocks with even smaller
and more complex pores, but were unable to harness the resource—the oil
and gas flowed too slowly or not at all from these rocks. Instead of driving
on a large and fast highway, flowing through these rocks would be like
driving on a small two-lane road with many stoplights and intersections.
Conventional gas wells drilled into these formations were considered
uneconomic since the gas locked in the rock would flow out of the tiny
pores in the rock at such low rates. This picture changed, and changed in a
big way, with the advent of stimulated horizontal wells.
Are We Running Out of Oil and Gas? Why is it valuable?
Countries with Largest Known Oil Reserves
• Saudi Arabia
• Canada
• Iran
• Iraq
• Kuwait
• United Arab Emirates
• Venezuela
• Russia
• Libya
• Nigeria
No one can know for certain how much oil and gas remains to be
discovered. But geologists sometimes make educated guesses.
The total amount of oil or gas in the reservoir is called original oil, or gas.
For a specific reservoir, engineers estimate this amount using information
about the size of the reservoir trap and properties of the rock. Some of the
original oil and gas deposited millions of years ago has been discovered,
while some remains undiscovered—the target of future exploration.
Discovered (or known) resources can be divided into proved reserves and
prospective or unproved (probable and possible) resources.
• Proved reserves are the quantities of oil or gas from known reservoirs
that are expected to be recoverable with current technology and at
current economic conditions.
• Prospective resources are those that may be recoverable in the future
with advanced technologies or under different economic conditions.
The Oil & Gas Journal (OGJ) estimates that at the beginning of 2009,
worldwide reserves were 1.34 trillion barrels of oil and 6,254 trillion
cubic feet (Tcf) of natural gas. The oil estimate is 16 billion barrels of
oil higher than in 2007, reflecting additional discoveries, improving
technology and changing economics.
Continental North America and much of continental Europe have already
been explored heavily, and any new discoveries are likely to be small. But
many areas of the globe are largely unexplored, and large new deposits are
waiting to be found. Global hot spots that may house significant new oil
and gas reservoirs include:
• Offshore Brazil
• The Gulf of Mexico
• Alaska
• Offshore western Africa
• Russia
• Areas across Asia and the Pacific.
These are just a few of the current areas of growth. Most observers agree
that significant deposits of oil and gas remain undiscovered in the Middle
East.
The largest reserves of natural gas are found in Russia, Iran, Qatar, Saudi
Arabia, the United Arab Emirates, the United States, Algeria, Nigeria,
Venezuela and Iraq.
At current consumption levels, the remaining reserves represent 44.6 years
of oil and 66.2 years of natural gas. Does this mean that the world will be
out of fossil fuels in 50 years or so? That theory has been around since the
1970s. In fact, the figures for years of remaining reserves have remained
relatively constant during the past few decades as the industry has
balanced consumption with newly discovered oil and gas deposits.
Policy – Hydraulic Fracturing or “Fracking”
Info from www.energyfromshale.org
What is it?
In a hydraulic fracturing job, "fracturing fluids" or "pumping fluids"
consisting primarily of water and sand are injected under high pressure into
the producing formation, creating fissures that allow resources to move
freely from rock pores where it is trapped.
Typically, steel pipe known as surface casing is cemented into place at the
uppermost portion of a well for the explicit purpose of protecting the
groundwater. The depth of the surface casing is generally determined
based on groundwater protection, among other factors. As the well is
drilled deeper, additional casing is installed to isolate the formation(s) from
which oil or natural gas is to be produced, which further protects
groundwater from the producing formations in the well.
Casing and cementing are critical parts of the well construction that not
only protect any water zones, but are also important to successful oil or
natural gas production from hydrocarbon bearing zones. Industry well
design practices protect sources of drinking water from the other geologic
zone of an oil and natural gas well with multiple layers of impervious rock.
While 99.5 percent of the fluids used consist of water and sand, some
chemicals are added to improve the flow. The composition of the chemical
mixes varies from well to well.
- See more at: http://www.energyfromshale.org/hydraulic-fracturing/howhydraulic-fracturing-works#sthash.rwyXFMcQ.dpuf
Fracking: Economic Boom or
Environmental Danger?
http://politicsandpolicy.org/article/fracking-economic-boom-orenvironmental-danger
Politics & Policy takes a look at the practice of "fracking," what it is and
what its implications are.
Earthquakes are a rarity in Youngstown, Ohio but the holidays saw just such
excitement as residents experienced two earthquakes, which registered 2.7
and 4.0 on the Richter scale. The earthquakes resulted in no casualties and
relatively minor damage, but the historical paucity of earthquakes in the
region has led officials to question nearby fracking operations. Hydraulic
fracturing, fracking, is a process of drilling for natural gas which has stirred
up controversy between environmental and scientific groups—which
question its safety—and pro-business groups—which support the economic
benefits of recovering potentially massive quantities of natural gas. This
week, Politics & Policy will attempt to sort through the controversy, explain
exactly what fracking is and whether it is truly as dangerous as some critics
have suggested.
The process of fracking involves drilling into the ground and detonating
small explosives in order to open shale rocks with natural gas and oil
packed near the bottom of the well. Water, sand, and chemicals are then
injected at high pressures to allow gas and oil to flow more easily to the
surface. When the final stage is complete, fracturing plugs are removed and
the well is tested for results. Thereafter the liquid pressure is reduced, and
the waste water and fluids are removed for disposal or re-use. The drilling
can occur vertically, but more often paths are carved horizontally to the
rock layer. The process is useful not only for creating new paths to release
gas, but also for extending existing ones.
Today, fracking operations are ongoing across the world, in countries like
Canada, New Zealand, and the United Kingdom to name a few. In the US,
fracking has its roots in the 1860s, when nitroglycerin was used to open up
shallow, hard rock wells in Pennsylvania, Kentucky, New York, and West
Virginia. In the 20th century, nonexplosive fluids like acid were proposed to
stimulate oil wells, and by 1949 Stanolind Oil had not only perfected the
process of hydraulic fracturing, but had also created a formula for the fluids
necessary for the practice. The rising cost of oil—as well as the increasing
scarcity of natural gas—have improved the value of shale gas in recent
years, leading to large increase in fracking operations in the United States.
As the use of fracking has increased, so have environmentalist concerns
over dangers of pollution and groundwater contamination. Since 2005, the
EPA has had no authority to prosecute the possible pollution of hydraulic
fracturing operations under the Safe Drinking Water Act; these companies
currently enjoy the Haiburton Loophole—named after the first company
licensed to practice fracking—which frees the practice from regulation.
Hydraulic fracturing received an all-clear from the EPA in a 2004 study
which denied any connection between drinking water contamination and
fracking. Yet other, non-EPA funded studies, have found that fracking
increases levels of methane, radioactivity and toxic fracturing fluids in the
groundwater near well sites which can lead to, among other things,
flammable tap water. It was not until 2010 that the EPA reopened an
investigation into cases of contaminated groundwater and wells around
areas where hydraulic fracturing occurs. Fracking is known to release a
group of chemicals called BTEX, which have harmful effects on the nervous
system and have been shown to cause birth defects and cancer.
There has been a slow push by the federal government to enact some
environmental regulation in order to keep up with the eagerness of the
industry to expand the practice. As natural gas prices have risen and its use
as an alternative to oil has spread, natural gas has become a large export of
the United States. North Dakota and other western states are experiencing
huge economic booms from usage of hydraulic fracturing. Consequently,
energy companies have gone on the offensive to shore up the public image
of fracking. In November of last year CNBC quoted an unnamed CEO’s
whose company maintains fracking operations in Pennsylvania as saying
that his company must use “psychological warfare” to battle the angry
attacks faced in packed town hall meetings near well sites.
Separate from concerns over contaminated groundwater are the geologic
effects of fracking. The British government recently shut down a fracturing
operation in the north of England after company officials admitted the
practice had caused, “a number of minor seismic events,” while the U.S.
Geological Survey has pointed to additional occurrences in the U.S, Canada
and Japan as evidence that there is a link between fracking and
earthquakes.
The process of hydraulic fracturing engenders a cost-benefit analysis
between the potentially massive economic benefit and the equally sizable
environmental and health problems. The practice has increased rapidly,
and it seems that serious research into its side effects are only now
beginning to catch up. It is important that the process be carefully
examined by the U.S. government and others to determine its true cost and
create a basis for regulation. Only then will the apprehensive residents of
Youngstown, Ohio and other fracking hubs be able to sleep peacefully.