HR: 0800h
AN: NG31A-0865    [Abstracts]
TI: Thermal Gradients Effects on Slow Dynamics in Geomaterials
AU: * Pasqualini, D
EM: dondy@lanl.gov
AF: LOS ALAMOS NATIONAL LABORATORY, P.O.Box 1663, Los Alamos, NM 87545 United States
AB: In recent years several anomalous elastic phenomena have been seen in different materials as rocks, sandstones. Perhaps one of the most interest and unsolved feature is the so-called slow dynamics. Slow dynamics has been seen in resonance bar experiments and consists of a time-dependent recovery of an elastic modulus to its initial value after being softened by large strain. Based on the observation of intermediate-time relaxation for individual cracks in a solid, it has been suggested recently that slow decrease of temperature gradients can account for the observed long-time behavior in resonant bar experiments for both cracked and undamaged materials. Here we critically examine this proposal and discuss several possible implementations (based on differing assumptions and simplifications).
DE: 5100 PHYSICAL PROPERTIES OF ROCKS
DE: 5199 General or miscellaneous
SC: Nonlinear Geophysics [NG]
MN: 2004 AGU Fall Meeting