Patent attributes
A method and apparatus for determining petrophysical parameters within a geologic formation pressurizes a geologic sample through a set of predetermined effective pressures, energizes the sample at each predetermined effective pressure with an electric current and/or sonic energy, and measures a conductivity value (electrical conductivity and/or sonic velocity). Permeability and/or porosity are also measured at each pressure through a traditional method and the functions are compared so that permeability and/or porosity can be subsequently derived from a sonic or electrical measurement of a comparable sample under a effective pressure. An apparatus is also described for acquiring the measurements under tri-axial compression, with a computerized interface in one embodiment.