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GLOSSARY
Acid deposition: Acid rain; a form of pollution depletion in which
pollutants, such as nitrogen oxides and sulfur oxides, are transferred from the atmosphere to soil or water; often referred to as
atmospheric self-cleaning. The pollutants usually arise from the
use of fossil fuels.
Acid rain: The precipitation phenomenon that incorporates anthropogenic acids and other acidic chemicals from the atmosphere
to the land and water (see Acid deposition).
Acoustic log: A display of travel time of acoustic waves versus
depth in a well; the term is commonly used as a synonym for a
sonic log; some acoustic logs display velocity.
Afterflow: The flow associated with wellbore storage following a
surface shut-in. When a well is first shut in at the surface, flow
from the formation into the bottom of the wellbore continues
unabated until compression of the fluids in the wellbore causes
the downhole pressure to rise; if the wellbore fluid is highly
compressible and the well rate is low, the afterflow period can
be long; conversely, high-rate wells producing little gas have
negligible afterflow periods.
Air-blown asphalt: Asphalt produced by blowing air through
residua at elevated temperatures.
Air pollution: The discharge of toxic gases and particulate matter introduced into the atmosphere, principally as a result of
human activity.
Alcohol: The family name of a group of organic chemical compounds composed of carbon, hydrogen, and oxygen. The molecules in the series vary in chain length and are composed of a
hydrocarbon plus a hydroxyl group. Alcohol includes methanol
and ethanol.
Alkylation: A process for manufacturing high octane blending
components used in unleaded petrol or gasoline.
Alumina (A1 2 0 3 ): Used in separation methods as an adsorbent and
in refining as a catalyst.
American Society for Testing and Materials (ASTM): The official
organization in the United States for designing standard tests
for petroleum and other industrial products.
Anaerobic digestion: Decomposition of biological wastes by
micro-organisms, usually under wet conditions, in the absence
of air (oxygen), to produce a gas comprising mostly methane
and carbon dioxide.
GLOSSARY
Acid deposition: Acid rain; a form of pollution depletion in which
pollutants, such as nitrogen oxides and sulfur oxides, are transferred from the atmosphere to soil or water; often referred to as
atmospheric self-cleaning. The pollutants usually arise from the
use of fossil fuels.
Acid rain: The precipitation phenomenon that incorporates anthropogenic acids and other acidic chemicals from the atmosphere
to the land and water (see Acid deposition).
Acoustic log: A display of travel time of acoustic waves versus
depth in a well; the term is commonly used as a synonym for a
sonic log; some acoustic logs display velocity.
Afterflow: The flow associated with wellbore storage following a
surface shut-in. When a well is first shut in at the surface, flow
from the formation into the bottom of the wellbore continues
unabated until compression of the fluids in the wellbore causes
the downhole pressure to rise; if the wellbore fluid is highly
compressible and the well rate is low, the afterflow period can
be long; conversely, high-rate wells producing little gas have
negligible afterflow periods.
Air-blown asphalt: Asphalt produced by blowing air through
residua at elevated temperatures.
Air pollution: The discharge of toxic gases and particulate matter introduced into the atmosphere, principally as a result of
human activity.
Alcohol: The family name of a group of organic chemical compounds composed of carbon, hydrogen, and oxygen. The molecules in the series vary in chain length and are composed of a
hydrocarbon plus a hydroxyl group. Alcohol includes methanol
and ethanol.
Alkylation: A process for manufacturing high octane blending
components used in unleaded petrol or gasoline.
Alumina (A1 2 0 3 ): Used in separation methods as an adsorbent and
in refining as a catalyst.
American Society for Testing and Materials (ASTM): The official
organization in the United States for designing standard tests
for petroleum and other industrial products.
Anaerobic digestion: Decomposition of biological wastes by
micro-organisms, usually under wet conditions, in the absence
of air (oxygen), to produce a gas comprising mostly methane
and carbon dioxide.