6 - New Analysis of Shock-Compression Data for Selected Silicates

Summary

The study of minerals under shock compression provides fundamental constraints on their response to conditions of extreme pressure, temperature, and strain rate and has applications to understanding meteorite impacts and the deep Earth. The recent development of facilities for real-time in situ X-ray diffraction studies under gun- or laser-based dynamic compression provides new capability for understanding the atomic-level structure of shocked solids. Here traditional shock pressure-density data for selected silicate minerals (garnets, tourmaline, nepheline, topaz, and spodumene) are examined through comparison of their Hugoniots with recent static compression and theoretical studies. The results provide insights into the stability of silicate structures and the possible nature of high-pressure phases under shock loading. This type of examination highlights the potential for in situ atomic-level measurements to address questions about phase transitions, transition kinetics, and structures formed under shock compression for silicate minerals.