Irreversible phase transitions and wave propagation in silicate geologic materials

Journal Article · Wed Aug 15 04:00:00 EDT 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.346635· OSTI ID:6480808

Swegle, J W ^[1]

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1. Department of Solid Dynamics, Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (USA)

Shock and unloading experiments on quartz and silicate rocks indicate that the release adiabats lie below the Hugoniot. The hysteresis and energy dissipation inherent in this situation have important wave propagation implications. On loading, there is a pressure-induced transition to the stishovite phase which does not occur under conditions of thermodynamic equilibrium, in that the Hugoniot passes through a metastable mixed-phase region for several tens of GPa. One interpretation of the unloading data is that the transition is not reversible, and the phase mixture remains frozen on unloading. However, material strength may also play a role. A complete thermodynamically consistent equation of state which includes phase transitions and strength effects has been developed and used to examine shock and release data on quartz and silicate rocks in order to quantify the kinetics of the reverse transition and to separate the hysteretic effects due to reverse phase transition kinetics from those due to material strength. The model allows quantitative determination of the effect of reverse transition kinetics on ground shock propagation in silicate materials.

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6480808
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 68:4; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CHALCOGENIDES
ENERGY LOSSES
EQUATIONS
EQUATIONS OF STATE
GEOLOGIC STRUCTURES
HYSTERESIS
IRREVERSIBLE PROCESSES
LOSSES
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
QUARTZ
SHOCK WAVES
SILICATE MINERALS
SILICON COMPOUNDS
SILICON OXIDES
WAVE PROPAGATION