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86 items
Acoustic transit time
Composite capture cross section of the formation (Schlumberger thermal decay time tool)
Amplitude transmission coefficient in seismic reflection and refraction
Epithermal neutron diffusion coefficient
Apparent intensity reflected by recorder (gamma ray)
Fraction of total porosity occupied by clays
Apparent resistivity
Hingle nonlinear-resistivity/linear-porosity crossplot
Apparent sorption compressibility
Oil saturation determination (IE and CDN logs)
Atlas wireline neutron lifetime log
Relation between concentration of K, Th, or U and recorded total gamma ray signal
Barenblatt-Chorin universal velocity distribution
Sonic porosity (Raymer Hunt Gardner method)
Coefficient of reflection
Volumetric photoelectric absorption cross section
Compaction correction factor for sonic logs in shale lithology
Correlation of mud cake resistivity to mud resistivity
Correlation of mud filtrate resistivity to mud resistivity
Diffuse-layer thickness
Effect of clay on conductivity
Effective photoelectric absorption cross section index
Electric resistance to a radial current from a wellbore
Electrochemical potential (SP log)
Electrokinetic potential (developed across a mud cake)
Electron density index (GR absorbtion logging)
Epithermal neutron distribution (epithermal neutron flux)
Fertl and Hammack equation
Formation conductivity in dual water model
Formation factor - Archie's equation
Formation factor (Archie's equation with resistivity logs)
Formation resistivity and permeability (Carothers) relation for limestones
Formation resistivity and permeability (Carothers) relation for sandstones
Formation resistivity and porosity relations for carbonate rocks
Formation resistivity and porosity relations from well log data based on Porter and Carothers data
Fresh water-filled porosity (fresh-water-bearing limestones)
Fxo / Fs approach
Gamma ray log shale index
General form of the Archie equation-Water saturation from resistivity logs
Generalized relationship between formation resistivity factor and porosity (Chevron formula)
Geometric coefficient for the electrode
Geometric coefficient for the lateral device
Geometric coefficient for the normal sonde
Half thickness value
Humble equation (formation resistivity factor vs porosity)
Integrated radial geometric factor
Lennard Jones potential
Linear absorption (attenuation) coefficient
Maximum potential for self-potential (SP) log
Mean free path (photon absorption)
Membrane potential
Neutron lethargy (logarithmic energy decrement)
Neutron porosity of shale zone
Pair production (gamma ray interactions)
Phillips equation (sandstones)
Photoelectric absorption cross sectional area
Pickett crossplot
Poisson's ratio (seismic arrival time method)
Porosity by using density log data
Porosity corrected for gas effect
Porosity-neutron flux relationship
Rate of radioactive decay
Relationship between rock resistivity and water saturation
Relationship between SSP and Rw (NaCl predominant)
Relationship between SSP and Rw (non-ideal shale membrane)
Relationship between SSP and Rw for water containing salts (non-NaCl predominant)
Resistivity of a partially saturated shaly sand with hydrocarbons (Vsh models)
Resistivity of a water-saturated shaly sand (Vsh models)
Rock conductivity (relatively clean water bearing rocks)
Shale index from gamma ray spectrometry
Simandoux (total shale) equation
Spacing between transmitter and receiver
Static self potential
Time between the initiation of the pulse and the first arrival acoustic energy at the receiver
Time-average relation in compacted formations (porosity/transit time relationships)
Time-average relation in uncompacted formations (porosity/transit time relationships)
Tortuosity (resistivity logs)
Total rock conductivity
True porosity from sonic log (corrected for compaction)
True resistivity - Archie
Water salinity index ratio
Water saturation determination (IE and CDN logs)
Water saturation from neutron tools
Water saturation - Resistivity logs
Wavelength equation
Wellbore electric voltage generation