Collisions that induce melting and vaporization can have a substantial effect on the thermal and geochemical evolution of planets. However, the thermodynamics of major minerals are not well known at the extreme conditions attained during planet formation.We obtained new data at the Sandia Z Machine and use published thermodynamic data for the major mineral forsterite (Mg2SiO4) to calculate the specific entropy in the liquid region of the principal Hugoniot.We use our calculated specific entropy of shocked forsterite, and revised entropies for shocked silica, to determine the critical impact velocities for melting or vaporization upon decompression from the shocked state to 1 bar and the triple points, which are near the pressures of the solar nebula.We also demonstrate the importance of the initial temperature on the criteria for vaporization. Applying these results to N-body simulations of terrestrial planet formation, we find that up to 20% to 40% of the total system mass is processed through collisions with velocities that exceed the criteria for incipient vaporization at the triple point. Vaporizing collisions between small bodies are an important component of terrestrial planet formation.
Davies, E. J., et al. "Silicate Melting and Vaporization During Rocky Planet Formation." Journal of Geophysical Research. Planets, vol. 125, no. 2, Feb. 2020. https://doi.org/10.1029/2019JE006227
Davies, E. J., Carter, P. J., Root, S., Kraus, R. G., Spaulding, D. K., Stewart, S. T., & Jacobsen, S. B. (2020). Silicate Melting and Vaporization During Rocky Planet Formation. Journal of Geophysical Research. Planets, 125(2). https://doi.org/10.1029/2019JE006227
Davies, E. J., Carter, P. J., Root, S., et al., "Silicate Melting and Vaporization During Rocky Planet Formation," Journal of Geophysical Research. Planets 125, no. 2 (2020), https://doi.org/10.1029/2019JE006227
@article{osti_1633890,
author = {Davies, E. J. and Carter, P. J. and Root, S. and Kraus, R. G. and Spaulding, D. K. and Stewart, S. T. and Jacobsen, S. B.},
title = {Silicate Melting and Vaporization During Rocky Planet Formation},
annote = {Collisions that induce melting and vaporization can have a substantial effect on the thermal and geochemical evolution of planets. However, the thermodynamics of major minerals are not well known at the extreme conditions attained during planet formation.We obtained new data at the Sandia Z Machine and use published thermodynamic data for the major mineral forsterite (Mg2SiO4) to calculate the specific entropy in the liquid region of the principal Hugoniot.We use our calculated specific entropy of shocked forsterite, and revised entropies for shocked silica, to determine the critical impact velocities for melting or vaporization upon decompression from the shocked state to 1 bar and the triple points, which are near the pressures of the solar nebula.We also demonstrate the importance of the initial temperature on the criteria for vaporization. Applying these results to N-body simulations of terrestrial planet formation, we find that up to 20% to 40% of the total system mass is processed through collisions with velocities that exceed the criteria for incipient vaporization at the triple point. Vaporizing collisions between small bodies are an important component of terrestrial planet formation.},
doi = {10.1029/2019JE006227},
url = {https://www.osti.gov/biblio/1633890},
journal = {Journal of Geophysical Research. Planets},
issn = {ISSN 2169-9097},
number = {2},
volume = {125},
place = {United States},
publisher = {American Geophysical Union},
year = {2020},
month = {02}}
2007 IEEE International Pulsed Power Plasma Science Conference (PPPS 2007), 2007 16th IEEE International Pulsed Power Conferencehttps://doi.org/10.1109/PPPS.2007.4652354