Hysteresis, Discrete Memory and Nonlinear Wave Propagation in Rock: A New Paradigm

R. A. Guyera and K. R. McCallb
Earth and Environmental Sciences Division,
Los Alamos National Laboratory, Los Alamos, NM 87545

G. N. Boitnott
New England Research Inc., 76 Olcott Dr.,
White River Junction, VT 05001
(August 16, 1995)

[a] Present Address: Department of Physics and Astronomy, University of Massachusetts, Amherst, MA 01003.
[b] Also at Department of Physics, New Mexico State University, Las Cruces, NM 88003.


Abstract

The structural elements in a rock are characterized by their density in Preisach-Mayergoyz space (P-M space). This density is found for a Berea sandstone from stress-strain data and used to study the response of the sand-stone to elaborate pressure protocols. Hysteresis with discrete memory, in agreement with experiment, is found. The relationship between strain, qua-sistatic modulus, and dynamic modulus is established. Nonlinear wave prop-agation, the production of copious harmonics and nonlinear attenuation are demonstrated. P-M space is shown to be the central construct in a new paradigm for the description of the elastic behavior of consolidated materials.
91.60.Ba, 91.60.Fe, 91.60.Lj, 83.80.Nb