Glossary of Geophysical Terms (J,K,L)

Karst
Topographic area which has been created by the dissolution of carbonate rock terrain. It is characterized by caverns, sinkholes, and the absence of surface streams.
Lag
The distance a nuclear logging probe moves during one time constant.
Last reading
The depth of the shallowest value recorded on a log.
Lateral log
A multielectrode, resistivity-logging technique that has a much greater radius of investigation than the normal techniques, but requires thick beds and produces an unsymmetrical curve.
Laterolog
A focused-resistivity logging technique; see also guard log.
Light-non-aqueous phase liquids (LNAPLs)
Organic fluids that are less dense than water. They are capable of forming an immiscible layer that floats on the water table (e.g. petroleum hydrocarbons or other organic liquids). Also referred to as Floaters.
Long normal log
A resistivity log with AM spacing usually 64 in.; see normal logs.
Lag
The distance a nuclear logging probe moves during one time constant.
Last reading
The depth of the shallowest value recorded on a log.
Lateral log
A multielectrode, resistivity-logging technique that has a much greater radius of investigation than the normal techniques, but requires thick beds and produces an unsymmetrical curve.
Laterolog
A focused-resistivity logging technique; see also guard log.
Light-non-aqueous phase liquids (LNAPLs)
Organic fluids that are less dense than water. They are capable of forming an immiscible layer that floats on the water table (e.g. petroleum hydrocarbons or other organic liquids). Also referred to as Floaters.
Long normal log
A resistivity log with AM spacing usually 64 in.; see normal logs.
Lag
The distance a nuclear logging probe moves during one time constant.
Last reading
The depth of the shallowest value recorded on a log.
Lateral log
A multielectrode, resistivity-logging technique that has a much greater radius of investigation than the normal techniques, but requires thick beds and produces an unsymmetrical curve.
Laterolog
A focused-resistivity logging technique; see also guard log.
Light-non-aqueous phase liquids (LNAPLs)
Organic fluids that are less dense than water. They are capable of forming an immiscible layer that floats on the water table (e.g. petroleum hydrocarbons or other organic liquids). Also referred to as Floaters.
Long normal log
A resistivity log with AM spacing usually 64 in.; see normal logs.