Open AccessA comparison of laboratory measured electrical conductivity in rocks with theoretical conductivity based on derived pore aspect ratio spectra
Author(s) -
Evans C. J.,
Chroston P. N.,
ToussaintJackson J. E.
Publication year - 1982
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1982.tb04997.x
Subject(s) - electrical resistivity and conductivity , conductivity , spectral line , power law , pore water pressure , mineralogy , materials science , shear (geology) , geology , thermodynamics , condensed matter physics , geotechnical engineering , composite material , chemistry , physics , mathematics , quantum mechanics , astronomy , statistics
Summary. Compressional and shear wave velocities and electrical conductivity have been measured simultaneously on three saturated samples of granite up to 0.4 GPa effective pressure and one of chalk up to 0.04 GPa effective pressure. The velocity–pressure data have been inverted using the non‐interactive theory of Kuster & Toksöz to produce pore aspect ratio spectra. Archie's Law, and a model devised by Hoening have been used to calculate a theoretical electrical conductivity from the derived pore spectra. In general there is good agreement between the observed conductivity and the conductivity calculated using Hoening's equation applied to ‘cigar‐shaped’ cracks. Predicted conductivities obtained via Archie's Law are in approximate agreement using a power of two and are much less than the observed values using a power of one. The results suggest that simultaneous electrical conductivity measurements might provide an important constraint in interpreting velocity—pressure data in terms of pore spectra.