Oil and Gas at Your Door? (2005 Edition) - Earthworks

Chapter I
Oil and Gas Development and Impacts
TERMS AND CONCEPTS
This first section is designed to introduce readers to some key terms and concepts related to
oil and gas.
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STAGES OF DEVELOPMENT
The chapter continues with explanations of the various stages involved in oil and gas development:
from mineral leasing to the abandonment of oil and gas wells. Also included are some of
the issues and impacts associated with these stages of development that may be of concern to
landowners.
DEVELOPMENT OF NONCONVENTIONAL OIL AND GAS
This section introduces readers to the development of various forms of nonconventional oil and
gas. These types of oil and gas deposits are likely to become more heavily exploited in the
future.
IMPACTS OF OIL AND GAS DEVELOPMENT
This section provides information for landowners on some of the potential effects of oil and gas
development on their lands, livelihoods and quality of life.
ALTERNATIVE TECHNOLOGIES—MINIMIZING IMPACTS
The final section provides an overview of some of the “best practices” or alternatives that are
available to companies to minimize the impacts that their operations will have on the environment
and the lives of landowners and nearby residents.
Terms and Concepts
Crude oil is the term for unprocessed oil, and it is also known as petroleum. It is a mixture of
molecules that are composed primarily of hydrogen and carbon atoms (hydrocarbons).
Petroleum got its name from the fact that hydrocarbons are found in rock. The Latin words for
rock and oil are petra and oleum.
Hydrocarbons are formed from dead plant and animal (i.e., organic) matter. Over time, these
materials are covered by layers of sediment. The slow decay of the organic matter, aided by high
temperatures and pressures, completes a long and complex process of transforming the organic
material into hydrocarbons such as coal, oil and natural gas.
We often envision oil and gas reservoirs as being underground lakes of oil capped by natural
gas (which is less dense, and therefore rises above the oil). In reality, oil and gas are most often
located in the pores of rock. The beds of sedimentary rock in which the petroleum is formed are
called the source rocks, and usually these are dark grey or black shales. Because petroleum is
a fluid, it is able to migrate through the earth. Through time, the oil and gas migrate from the
source shales, which are not very porous, into more porous or permeable rocks. Petroleum may
end up in any porous rock, but it is most common to
find large reservoirs of hydrocarbons in highly permeable,
sedimentary rocks such as sandstone or limestone.
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