Отправлено: 15.12.11 05:01. Заголовок: Joint elastic-electrical properties of reservoir sandstones and their relationships with petrophysic

Geophysical Prospecting, 2011, 59, 518–535 doi: 10.1111/j.1365-2478.2010.00940.x

Joint elastic-electrical properties of reservoir sandstones and their relationships with petrophysical parameters

Tongcheng Han1∗‡, Angus I. Best1, Jeremy Sothcott1 and Lucy M. MacGregor2
1National Oceanography Centre, Southampton, University of Southampton Waterfront Campus, European Way, Southampton,
SO14 3ZH, UK, and 2OHM Ltd, The Technology Centre Offshore Technology Park, Claymore Drive, Bridge of Don, Aberdeen,
AB23 8GD, UK
Received May 2010, revision accepted October 2010
ABSTRACT
We measured in the laboratory ultrasonic compressional and shear-wave velocity
and attenuation (0.7–1.0 MHz) and low-frequency (2 Hz) electrical resistivity on
63 sandstone samples with a wide range of petrophysical properties to study the
influence of reservoir porosity, permeability and clay content on the joint elasticelectrical
properties of reservoir sandstones. P- and S-wave velocities were found to
be linearly correlated with apparent electrical formation factor on a semi-logarithmic
scale for both clean and clay-rich sandstones; P- and S-wave attenuations showed
a bell-shaped correlation (partial for S-waves) with apparent electrical formation
factor. The joint elastic-electrical properties provide a way to discriminate between
sandstones with similar porosities but with different clay contents. The laboratory
results can be used to estimate sandstone reservoir permeability from seismic velocity
and apparent formation factor obtained from co-located seismic and controlled source
electromagnetic surveys.