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Shock-produced olivine glass: First observation

Raymond Jeanloz·T.J. Ahrens·J.S. Lally·Gordon L. Nord·J.M. Christie·A.H. Heuer
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Abstract

Transmission electron microscope (TEM) observations of an experimentally shock-deformed single crystal of natural peridot, (Mg 0.88 Fe 0.12 ) 2 SiO 4 , recovered from peak pressures of about 56 × 10 9 pascals revealed the presence of amorphous zones located within crystalline regions with a high density of tangled dislocations. This is the first reported observation of olivine glass. The shocked sample exhibits a wide variation in the degree of shock deformation on a small scale, and the glass appears to be intimately associated with the highest density of dislocations. This study suggests that olivine glass may be formed as a result of shock at pressures above about 50 to 55 × 10 9 pascals and that further TEM observations of naturally shocked olivines may demonstrate the presence of glass.

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Raymond Jeanloz, T.J. Ahrens, J.S. Lally, Gordon L. Nord, J.M. Christie, A.H. Heuer. 1977. Shock-produced olivine glass: First observation. https://doi.org/10.1126/science.197.4302.457

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