there may be some degree of overlap between them to avoid too much cross reference
to other chapters.
Petroleum geology and geophysics are applied disciplines and practical experience is critical. A separate chapter on petroleum exploration is written by a geologist
with 40 years of experience from the Norwegian Continental shelf (Hans Rønnevik).
The Norwegian Continental Self (NCS) has been explored for nearly 50 years and
data from wells and seismic surveys is very well documented through the Norwegian
Petroleum Directorate and is accessible through their home page (www.npd.no).
They also have a very large collection of cores.
References to the original literature had to be limited because of the wide range of
disciplines. In the past, textbooks often included very extensive lists of references
which were very useful when searching for relevant literature. With the electronic
databases available now, it is easy to search for relevant references and new textbooks.
In this textbook, we have tried to bridge the gap that often seems to exist between
geophysical and geological disciplines and there is also an emphasis on sediment
compaction, fluid flow and rock physics. The skills required for a petroleum geologist have changed greatly over the years. Traditionally the main task was to identify
reservoir rocks, structures with closure and the proximity of a mature source rock.
We are running out of “the easy to find” and “easy to produce” oil and gas, and
exploration and production technology is becoming more advanced. It is now
possible to produce oil and gas from source rocks (shales) and not only what has
migrated into a reservoir rock. This has increased the world’s petroleum reserves
very significantly in recent years. In North America, shale gas and shale oil production has increased and has lowered the gas price also internationally.
Production of unconventional oil (tar sand, oil shale) and also tight gas reservoirs
and gas shale requires a stronger background in mineralogy, chemistry and physics.
The geophysical methods have become increasingly sophisticated and it is now
often possible to detect the presence of gas and oil prior to drilling based on seismic
data. Electromagnetic methods that were primarily used in mineral prospecting are
also used to find oil. As conventional oil is becoming more scarce, more geologists
are becoming involved with exploration and production of heavy oil, oil shales and
shale gas. Utilization of these resources may be environmentally more problematic
than conventional oil and gas and tends to cause increased CO 2 emission during
production.
This requires a stronger background in the chemistry and physics of petroleum
and also in mineralogy and rock mechanics (rock physics). Physical and chemical
modelling is also very important.
Even if alternative sources of energy are being developed, the world will require
fossil fuels for several decades. It is a great challenge to limit the environmental
consequences of the production and use of fossil energy.
Until sufficient low-cost renewable energy is available, geoscientists can contribute to efficient exploration and production of oil and gas, reducing pollution and CO 2
emissions as much as possible. They may also engage in developing carbon storage.
Much of the theoretical basis is the same for environmental geology and petroleum geology.
vi
Preface
to other chapters.
Petroleum geology and geophysics are applied disciplines and practical experience is critical. A separate chapter on petroleum exploration is written by a geologist
with 40 years of experience from the Norwegian Continental shelf (Hans Rønnevik).
The Norwegian Continental Self (NCS) has been explored for nearly 50 years and
data from wells and seismic surveys is very well documented through the Norwegian
Petroleum Directorate and is accessible through their home page (www.npd.no).
They also have a very large collection of cores.
References to the original literature had to be limited because of the wide range of
disciplines. In the past, textbooks often included very extensive lists of references
which were very useful when searching for relevant literature. With the electronic
databases available now, it is easy to search for relevant references and new textbooks.
In this textbook, we have tried to bridge the gap that often seems to exist between
geophysical and geological disciplines and there is also an emphasis on sediment
compaction, fluid flow and rock physics. The skills required for a petroleum geologist have changed greatly over the years. Traditionally the main task was to identify
reservoir rocks, structures with closure and the proximity of a mature source rock.
We are running out of “the easy to find” and “easy to produce” oil and gas, and
exploration and production technology is becoming more advanced. It is now
possible to produce oil and gas from source rocks (shales) and not only what has
migrated into a reservoir rock. This has increased the world’s petroleum reserves
very significantly in recent years. In North America, shale gas and shale oil production has increased and has lowered the gas price also internationally.
Production of unconventional oil (tar sand, oil shale) and also tight gas reservoirs
and gas shale requires a stronger background in mineralogy, chemistry and physics.
The geophysical methods have become increasingly sophisticated and it is now
often possible to detect the presence of gas and oil prior to drilling based on seismic
data. Electromagnetic methods that were primarily used in mineral prospecting are
also used to find oil. As conventional oil is becoming more scarce, more geologists
are becoming involved with exploration and production of heavy oil, oil shales and
shale gas. Utilization of these resources may be environmentally more problematic
than conventional oil and gas and tends to cause increased CO 2 emission during
production.
This requires a stronger background in the chemistry and physics of petroleum
and also in mineralogy and rock mechanics (rock physics). Physical and chemical
modelling is also very important.
Even if alternative sources of energy are being developed, the world will require
fossil fuels for several decades. It is a great challenge to limit the environmental
consequences of the production and use of fossil energy.
Until sufficient low-cost renewable energy is available, geoscientists can contribute to efficient exploration and production of oil and gas, reducing pollution and CO 2
emissions as much as possible. They may also engage in developing carbon storage.
Much of the theoretical basis is the same for environmental geology and petroleum geology.
vi
Preface