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USGS · 70221797

Maskelynite: Formation by explosive shock

Daniel J. Milton·P. S. De Carli
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Abstract

When high pressure (250 to 300 kilobars) was applied suddenly (shock-loading) to gabbro, the plagioclase was transformed to a noncrystalline phase (maskelynite) by a solid-state reaction at a low temperature, while the proxene remained crystalline. The shock-loaded gabbro resembles meteorites of the shergottite class; this suggests that the latter formed as a result of shock. The shock-loading of gabbro at 600 to 800 kilobars raised the temperature above the melting range of the plagioclase.

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Daniel J. Milton, P. S. De Carli. 1963. Maskelynite: Formation by explosive shock. https://doi.org/10.1126/science.140.3567.670

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