T.J. Ahrens J.S. Lally Gordon L. Nord Jr. J.M. Christie A.H. Heuer Raymond Jeanloz 1977 <p><span>Transmission electron microscope (TEM) observations of an experimentally shock-deformed single crystal of natural peridot, (Mg</span>_0.88<span>Fe</span>_0.12<span>)</span>₂<span>SiO</span>₄<span>, recovered from peak pressures of about 56 × 10</span>⁹<span>&nbsp;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</span>⁹<span>&nbsp;pascals and that further TEM observations of naturally shocked olivines may demonstrate the presence of glass.</span></p> application/pdf 10.1126/science.197.4302.457 en American Association for the Advancement of Science Shock-produced olivine glass: First observation article