Organic Theory:
There are a number of compelling reasons that support an organic development
hypothesis.
First and foremost, is the carbon-hydrogen-organic matter connection. Carbon and
Hydrogen are the primary constituents of organic material, both plant and animal.
Moreover, carbon, hydrogen, and hydrocarbons are continually produced by the life
processes of plants and animals. A major breakthrough occurred when it was discovered
that hydrocarbons and related compounds occur in many living organisms and are
deposited in the sediments with little or no change.
Second were observations dealing with the chemical characteristics of petroleum
reservoirs. Nitrogen and porphyrins (chlorophyll derivatives in plants, blood derivatives
in animals) are found in all organic matter; they are also found in many petroleums.
Presence of porphyrins also mean that anaerobic conditions must have developed early in
the formation process because porphyrins are easily and rapidly oxidized and decompose
under aerobic conditions. Additionally, low Oxygen content also implies a reducing
environment. Thus there is a high probability that petroleum originates within an
anaerobic and reducing environment.
Third were observations dealing with the physical characteristics. Nearly all petroleum
occurs in sediments that are primarily of marine origin. Petroleum contained in nonmarine sediments probably migrated into these areas from marine source materials
located nearby. Furthermore, temperatures in the deeper petroleum reservoirs seldom
exceed 300oF (141 oC) . But temperatures never exceeded 392oF (200oC) where
porphyrins are present because they are destroyed above this temperature. Therefore the
origin of petroleum is most likely a low-temperature phenomenon.
Finally, time requirements may be less than 1MM years; this is based on more recent oil
discoveries in Pliocene sediments.
However, physical conditions on the Earth may have been different in the geologic past
and therefore it may have taken considerably more time to develop liquid petroleum.
Organic Hypothesis - Summary.
The organic theory became the accepted theory about the turn of the century as the oil
and gas industry began to fully develop and geologists were exploring for new deposits.
Simply stated, the organic theory holds that the carbon and hydrogen necessary for the
formation of oil and gas were derived from early marine life forms living on the Earth
during the geologic past -- primarily marine plankton. Although plankton are
microscopic, the ocean contains so many of them that over 95% of living matter in the
ocean is plankton. The Sun's energy provides energy for all living things including
plankton and other forms of marine life .
As these early life forms died, their remains were captured by the processes of erosion
and sedimentation.
Successive layers of organic-rich mud and silt covered preceding layers of organic rich
sediments and over time created layers on the sea floor rich in the fossil remains of
previous life.
Thermal maturation processes (decay, heat, pressure) slowly converted the organic matter
into oil and gas. Add additional geologic time (millions of years) and the organic rich
sediments were converted into layers of rocks. Add more geologic time and the layers
were deformed, buckled, broken, and uplifted; the liquid petroleum flowed upward
through porous rock until it became trapped and could flow no further forming the oil and
gas reservoirs that we explore for at present (Fig. 4).
But the chemistry of the hydrocarbons found in the end product (oil, gas) differ
somewhat from those we find in living things. Thus changes, transformation, take place
between the deposition of the organic remains and the creation of the end product. The
basic formula for the creation of petroleum (oil, gas) is:
Petroleum End Product = ([Raw Material + Accumulation + Transformation + Migration]
+ Geologic Time)
Petroleum, according to the organic theory, is the product of altered organic material
derived from the microscopic plant and animal life, which are carried in great volumes by
streams and rivers to lakes or the sea, where they are deposited under deltaic, lacustrine
and marine conditions with finely divided clastic sediments.
These environments produce their own microscopic plant and animal life, which are
deposited with the organic materials introduced by the streams and rivers. As deposition
of the organic material takes place in these environments, burial and protection by clay
and silt accompany it. This prevents decomposition of the organic material and allows it
to accumulate.
Conversion of the organic material is called catagenesis. It is assisted by pressure caused
by burial, temperature and thermal alteration and degradation. These factors result from
depth, some bacterial action in a closed nonoxidising chemical system, radioactivity and
catalysis. Temperature, as thermogenic activity, appears to be the most important
criterion, with assistance other factors as applicable. Accumulation of organic and clastic
material on a sea or lake bottom is accompanied by bacterial action. If there is abundant
oxygen, aerobic bacteria act upon the organic matter and destroy it.
Plant and animal remains contain abundant carbon and hydrogen, which are fundamental
elements in petroleum. Shale and some carbonates contain organic material that bears
hydrocarbons of types similar to those in petroleum. These rocks are not reservoir rocks
and could be considered ultimately to be source beds. The hydrocarbons are of the same
type as those found in living plants and animals and consist of asphalt, kerogen and liquid
forms. The best source rocks are considered to be organically rich, black-coloured shales,
deposited in a non-oxidising, quiet marine environment.
https://www.youtube.com/watch?v=KLCraxU2YoY&feature=youtu.be
There are a number of compelling reasons that support an organic development
hypothesis.
First and foremost, is the carbon-hydrogen-organic matter connection. Carbon and
Hydrogen are the primary constituents of organic material, both plant and animal.
Moreover, carbon, hydrogen, and hydrocarbons are continually produced by the life
processes of plants and animals. A major breakthrough occurred when it was discovered
that hydrocarbons and related compounds occur in many living organisms and are
deposited in the sediments with little or no change.
Second were observations dealing with the chemical characteristics of petroleum
reservoirs. Nitrogen and porphyrins (chlorophyll derivatives in plants, blood derivatives
in animals) are found in all organic matter; they are also found in many petroleums.
Presence of porphyrins also mean that anaerobic conditions must have developed early in
the formation process because porphyrins are easily and rapidly oxidized and decompose
under aerobic conditions. Additionally, low Oxygen content also implies a reducing
environment. Thus there is a high probability that petroleum originates within an
anaerobic and reducing environment.
Third were observations dealing with the physical characteristics. Nearly all petroleum
occurs in sediments that are primarily of marine origin. Petroleum contained in nonmarine sediments probably migrated into these areas from marine source materials
located nearby. Furthermore, temperatures in the deeper petroleum reservoirs seldom
exceed 300oF (141 oC) . But temperatures never exceeded 392oF (200oC) where
porphyrins are present because they are destroyed above this temperature. Therefore the
origin of petroleum is most likely a low-temperature phenomenon.
Finally, time requirements may be less than 1MM years; this is based on more recent oil
discoveries in Pliocene sediments.
However, physical conditions on the Earth may have been different in the geologic past
and therefore it may have taken considerably more time to develop liquid petroleum.
Organic Hypothesis - Summary.
The organic theory became the accepted theory about the turn of the century as the oil
and gas industry began to fully develop and geologists were exploring for new deposits.
Simply stated, the organic theory holds that the carbon and hydrogen necessary for the
formation of oil and gas were derived from early marine life forms living on the Earth
during the geologic past -- primarily marine plankton. Although plankton are
microscopic, the ocean contains so many of them that over 95% of living matter in the
ocean is plankton. The Sun's energy provides energy for all living things including
plankton and other forms of marine life .
As these early life forms died, their remains were captured by the processes of erosion
and sedimentation.
Successive layers of organic-rich mud and silt covered preceding layers of organic rich
sediments and over time created layers on the sea floor rich in the fossil remains of
previous life.
Thermal maturation processes (decay, heat, pressure) slowly converted the organic matter
into oil and gas. Add additional geologic time (millions of years) and the organic rich
sediments were converted into layers of rocks. Add more geologic time and the layers
were deformed, buckled, broken, and uplifted; the liquid petroleum flowed upward
through porous rock until it became trapped and could flow no further forming the oil and
gas reservoirs that we explore for at present (Fig. 4).
But the chemistry of the hydrocarbons found in the end product (oil, gas) differ
somewhat from those we find in living things. Thus changes, transformation, take place
between the deposition of the organic remains and the creation of the end product. The
basic formula for the creation of petroleum (oil, gas) is:
Petroleum End Product = ([Raw Material + Accumulation + Transformation + Migration]
+ Geologic Time)
Petroleum, according to the organic theory, is the product of altered organic material
derived from the microscopic plant and animal life, which are carried in great volumes by
streams and rivers to lakes or the sea, where they are deposited under deltaic, lacustrine
and marine conditions with finely divided clastic sediments.
These environments produce their own microscopic plant and animal life, which are
deposited with the organic materials introduced by the streams and rivers. As deposition
of the organic material takes place in these environments, burial and protection by clay
and silt accompany it. This prevents decomposition of the organic material and allows it
to accumulate.
Conversion of the organic material is called catagenesis. It is assisted by pressure caused
by burial, temperature and thermal alteration and degradation. These factors result from
depth, some bacterial action in a closed nonoxidising chemical system, radioactivity and
catalysis. Temperature, as thermogenic activity, appears to be the most important
criterion, with assistance other factors as applicable. Accumulation of organic and clastic
material on a sea or lake bottom is accompanied by bacterial action. If there is abundant
oxygen, aerobic bacteria act upon the organic matter and destroy it.
Plant and animal remains contain abundant carbon and hydrogen, which are fundamental
elements in petroleum. Shale and some carbonates contain organic material that bears
hydrocarbons of types similar to those in petroleum. These rocks are not reservoir rocks
and could be considered ultimately to be source beds. The hydrocarbons are of the same
type as those found in living plants and animals and consist of asphalt, kerogen and liquid
forms. The best source rocks are considered to be organically rich, black-coloured shales,
deposited in a non-oxidising, quiet marine environment.
https://www.youtube.com/watch?v=KLCraxU2YoY&feature=youtu.be
