Petroleum Geology plays an important role in today's
society. Petroleum Geologists are the men and women who know how to read the
story told by the very earth beneath our feet in order to find oil and natural
gas, which are vital resources in our lives. Politics and prices often
overshadow the story of what happens before the oil and gas ever reaches the
headlines.
This website is built and maintained by actual
geologists, who want to share with you their passion for the Earth and what
they do. They want to answer your questions about where oil actually comes from
and share their role in exploring the wonders of our planet. Their goal is to
help you better understand the history of oil and gas exploration and the role
oil and gas plays in today's world. Who better to talk about these topics than
the very people who search for and discover oil and gas? At
PetroleumGeology.org, you can learn about the source, from the source!
Petroleum Past and Present
The history
of petroleum is almost as long as the history of civilization itself. There are
accounts of natural oil springs being utilized as early as ancient Babylon and
in China.
However,
the story of the Petroleum Industry as we know it begins in the nineteenth
century. This section provides information about the world's history with
petroleum, as well as the growth and evolution of the petroleum industry
What Is
Petroleum?
A thick,
flammable, yellow-to-black mixture of gaseous, liquid, and solid hydrocarbons
that occurs naturally beneath the earth's surface, can be separated into
fractions including natural gas, gasoline, naphtha, kerosene, fuel and
lubricating oils, paraffin wax, and asphalt and is used as raw material for a
wide variety of derivative products. (American Heritage Dictionary)
The word
petroleum comes from the Latin petra, meaning “rock,” and oleum, meaning “oil.”
The oil
industry classifies "crude" by the location of its origin and by its
relative weight or viscosity ("light", "intermediate" or
"heavy"). The relative content of sulfur in natural oil deposits also
results in referring to oil as "sweet," which means it contains
relatively little sulfur, or as "sour," which means it contains
substantial amounts of sulfur.
Petroleum
Exploration History
From the
time humans realized naturally occurring petroleum had myriad uses, they
organized means and methods to try and collect it and utilize it to its fullest
potential. The history of petroleum exploration around the world is colorful
and fascinating. Each country, and even regions within countries, has its own
distinct path of discovery that influences it to this day.
Museums
and Historical Sites
The history
of petroleum geoscience goes hand-in-hand with the history of the world. The
technology and culture of petroleum geology reflect those of the time, past and
present. There are many museums, memorials, and other historical establishments
commemorating the contributions of the petroleum industry to the world's
cultural landscape.
All About the Oil and Gas Industry
The oil and
gas industry is a diverse and vital part of the global economy. A wide range of
expertise goes into the discovery, production, and distribution of petroleum
products, and Petroleum Geology plays a central role in the exploration and
production process.
Oil and
Gas Prices
While
standing next to the fuel pump, many of us have all asked the same question:
"Why am I paying so much for gas?" Where does all the money go?
The answer
is not as straightforward as we might wish, but there are many great primers
out there for reference. For a good introduction to the oil market, check out
some of the following resources
This
section explains the business side of Petroleum Geology: what Petroleum
Geologists do in the industry, the economics of how the industry works, and --
yes -- why oil and gas prices are the way they are.
Careers
in the Oil and Gas Industry
The
petroleum industry is a growing, global industry with many opportunities for
those interested in the geosciences. The types of jobs are diverse and suit any
interests and personality types. There are careers to be had in virtually every
part of the world--the petroleum industry is a great gateway to foreign
countries and exotic locations.
If you're
wondering if a career in petroleum geoscience is for you, or if you'd just like
more information on what these men and women do in their jobs, check out the
links below.
Exploration
Today
The
petroleum industry involves people of all levels and areas of expertise, in
civilian and government sectors, non-profit and for-profit, all over the world.
The industry touches our everyday lives in many obvious ways, and petroleum
geologists are well aware of the impact their work has on their own lives, as
well as the lives of others all around the world. It truly does connect us all.
There are many
associations and organizations for petroleum geologists and others involved or
interested in the industry. People are brought together by common specialty,
geographic location, and other factors.
When Geology Meets Petroleum
There are
many ways the field of Geology contributes to the Petroleum Industry. The
varied disciplines of Geology explore the history of the Earth itself in hopes
of understanding in greater detail where oil comes from and where more oil
might be found, as well as the best ways to retrieve oil and utilize it once it
has been retrieved.
Sedimentology
and Stratigraphy
Sedimentology
studies sand, mud (or silt) and clay, and the various ways they are deposited.
Using these studies, sedimentologists apply their understanding of modern processes
to ancient rock, to try to understand how it formed.
Most of the
rocks on earth are sedimentary rocks, and it is in these kinds of rocks you
find fossils and many of the other historical markers. Sedimentary rocks are
also where petroleum deposits are found.
Sedimentology
is tied to stratigraphy, which studies the relationships between rock layers
and how they can shift and move. This also affects where petroleum deposits can
be found, as well as how the extraction of petroleum affects the sediment
around the deposit.
Structural
Geology
Structural
geology is the study of the three dimensional distribution of large bodies of
rock, their surfaces, and the composition of their inside in order to try and
learn about their tectonic history, past geological environments and events
that could have changed or deformed them. These can be dated to determine when
the structural features formed.
If the
nature of these rocks can be determined, petroleum geologists can discover if
petroleum, natural gas, or other natural resources are trapped within the
rocks.
Paleontology
and Biostratigraphy
Paleontology,
or palaeontology, is the study of prehistoric life forms on Earth through the
examination of plant and animal fossils. This includes the study of body
fossils, tracks (ichnites), burrows, cast-off parts, fossilised faeces
(coprolites), palynomorphs and chemical residues.
Biostratigraphy
uses those fossils, tracks, and other finds in an effort to figure out how old
a certain layer of rock and sediment is.
Once a
petroleum geologists knows how old a particular area is, they know the
potential for finding natural resources such as oil or natural gas.
Geochemistry
The field
of geochemistry involves study of the chemical composition of the Earth and
other planets, the composition of rocks and soils, the cycles that involve the
earth's chemical components, and the interaction of those cycles with land and
water.
Some
questions geochemistry tries to answer include what elements and chemicals are
present in various soils and rocks in different locations? What can we learn
from those differences? How are these soils and rocks changing, and how have
they changed through the centuries? How do once-living things like plants and
animals decompose after their deaths and what sorts of new things do they form
as they interact with the environment (such as fossils or hydrocarbons, a.k.a,
oil)? How do these various processes affect the environment, and how does the
environment, weather, and other influences affect them?
Seismology
and Geophysics
Geophysics
is the study of the Earth using physics to determine Earth properties. Some of
the physical properties studied are the earth's size and gravity, the weather
and atmosphere, volcanoes and hot springs, the oceans, water in the ground, and
the movements through the earth (otherwise known as seismology).
Plate
Tectonics
According
to the theory of Plate Tectonics, the surface of the Earth is comprised of
several plates, some very large, and several smaller. The plates slowly move
through time, changing size and shape. When the plates move against each other,
they create geologic events such as earthquakes, volcanoes, mountains. The type
of event depends on how the plates move relative to each other.
This
movement of the Earth's surface impacts where oil and natural gas deposits can
be found, which is why the study of Plate Tectonics is important to Petroleum
Geologists.
Seismology
studies seismic waves that move through and around the earth, including
earthquakes. Geophysicists can study how these waves move and affect the earth
to learn the nature of the earth deep below the surface, where it can't be
directly seen. The seismic waves can be from a naturally occurring event, like
an earthquake, or they can be artificially produced.
Paleogeography
Paleogeography
focuses on the way the earth looked in ancient times. This is done by studying
layers of rock, soil, artifacts, and fossils. Paleogeographers want to learn
more about the configuration and movement of the oeans and continents and what
kinds of plants and animals existed through history. They study how species of
plants and animals evolved, and how certain species became extinct.
These
ancient plants, animals, lands and seas have left traces today that give us
clues toward finding natural resources, such as oil and gas.
Geologic
Maps
Explorers
have been making maps for more than four thousand years! As explorers for oil
and gas, no introduction to petroleum geology is complete without first
discussing the geologic map.
A geology
map is used just like your handy highway map that you or your parents might
keep in their car. Important data is stored on that road map – locations of
cities, roads, mountains, and rivers – just to name a few. The geologic map is
used in much the same way, only instead of capturing surface features such as
cities and roads, the goal is to describe the subsurface. One of the most
common uses for geologic maps is by construction firms, as they need to look
for potential hazards such as faults before building buildings or roads.
Once We've Found It, What Do We Do With It?
Exploration
is only a part of the field of Petroleum Geology. There are many technologies
available to extract petroleum from the ground and then process it into one of
the hundreds of everyday items made from petroleum-based products. This section
talks about the structure of a found petroleum accumulation and the techology
used to model it for scientists to determine how to best utilize its resources,
as well as the refining process, and the end results of that process.
Petroleum
Products
You might
be surprised at the everyday items that are made with petroleum products. For
example:
Detergent
Fertilizer
Synthetic
fibers
Vitamins
Plastic
CDs / DVDs
Candles
(wax)
Band-Aids
Here are
some links to show that petroleum is for more than fueling our cars!
Tools of
the Trade
Petroleum
Geologists use a wide range of technologies to study the earth and its
properties. From simple hand tools to multi-million-dollar computers and
machinery, the variety of tools used in the study of petroleum geology is as
vast as the discipline itself.
Refining and Chemicals
It is a long path from finding oil in the ground to
using it in detergent to wash dishes after dinner. Before we put gasoline into
our fuel tanks or pick up some Tupperware at the grocery story, the petroleum
in these products passes through a refinery, and probably to a chemical plant.
In the oil industry, "Upstream" refers to
petroleum exploration and development. "Downstream" refers to
pipeline, refining, and chemicals.
As captured in the illustation below from the US
Department of Energy, of all the petroleum produced, only about 20% of it goes
to put gas in our cars. The rest goes to fueling our economy - literally! Take
a moment to look at your credit card - it's plastic! (part of those"other products").
Petroleum Chemistry
Petroleum comes from many different substances, such
as oil and natural gas, from which various products are derived, such as:
gasoline, kerosene propane, fuel oil, lubricating oil, wax, and asphalt. These
substances are mainly compounds of only two elements: carbon (C) and hydrogen
(H). They are called, therefore: hydrocarbons.
The specific study of petroleum is referred to as
petroleum geochemistry. Understanding petroleum geochemistry is critical in the
exploration and development of petroleum.
Anatomy
of an Oil Accumulation
A
hydrocarbon accumulation forms when six fundamental elements to develop in the
correct sequence: the source for the hydrocarbon (any carbon bearing element
such as plants or marine plankton), maturation (enough heat and pressure),
migration (movement of the hydrocarbon from deep in the subsurface to shallow),
reservoir (a porous sedimentary rock in which the liquid or gas hydrocarbon can
be held), trap, and seal (something preventing the hydrocarbon from leaking
out).
