Abstract
The entropy associated with the thermodynamic states produced by hypervelocity meteoroid impacts at various velocities are calculated for a series of lunar rocks and minerals and compared with the entropy values required for melting and vaporization.
Taking into account shock-induced phase changes in the silicates, we calculate that iron meteorites impacting at speeds varying from 4 to 6 km/s will produce shock melting in quartz, plagioclase, olivine, and pyroxene. Although calculated with less certainty, impact speeds required for incipient vaporization vary from ~ 7 to 11 km/s for the range of minerals going from quartz to periclase for aluminum (silicate-like) projectiles. The impact velocities which are required to induce melting in a soil, are calculated to be in the range of 3 to 4 km/s, provided thermal equilibrium is achieved in the shock state.
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Ahrens, T. J.: 1972,J. Appl. Phys., in press.
Ahrens, T. J. and Gaffney, E. S.: 1971,J. Geophys. Res. 76, 5489–5498.
Ahrens, T. J. and Graham, E. K.: 1972,Earth Planetary Sci. Letters, in press.
Ahrens, T. J., Anderson, D. L. and Ringwood, A. E.: 1969a,Rev. Geophys. 7 667–707.
Ahrens, T. J., Petersen, C. F. and Rosenberg, J. T.: 1969b,J. Geophys. Res. 74, 2727–2746.
Ahrens, T. J. and Rosenberg, J. T.: 1968, in French, B. M. and N. M. Short, (eds.),Shock Metamorphism of Natural Materials, Mono Book Corp., Baltimore, pp. 59–81.
Brewer, L.: 1953,Chem. Rev. 52, 1–75.
Butkovich, T. R.: 1967, ‘The Gas Equation of State for Natural Materials’, Lawrence Livermore Report, UCRL-14729.
Carter, J. L. and MacGregor, I. D.: 1970,Science 167, 661–663.
Carter, W. J., Marsh, S. P., Fritz, J. N., and McQueen, R. G.: 1971, inAccurate Characterization of the High Pressure Environment, (ed. by E. C. Lloyd), NBS Spec. Publ. 326, pp. 147–158.
Chao, E. C. T.: 1967,Science 156, 192–202.
Davies, G. F. and Anderson, D. L.: 1971,J. Geophys. Res. 76, 2617–2627.
De Carli, P. S. and Jamieson, J. C.: 1959,J. Chem. Phys. 31, 1675–1676.
De Carli, P. S. and Milton, D. J.: 1965,Science 147, 144–145.
Dieke, G. H.: 1963, inAmerican Inst. of Phys. Handbook, 2nd. Ed., Sect. 7.
Dundon, R. W. and Hafner, S. S.: 1971,Science 174, 581–583.
Furakawa, G. T. and Douglas, T. B.: 1963, inAmerican Inst. of Phys. Handbook, 2nd Ed., Sect. 4e.
Gibbons, R. V. and Ahrens, T. J.: 1971,J. Geophys. Res. 76, 5489–5498.
Glass, B. P.: 1971,J. Geophys. Res. 76, 5649–5657.
Horz, F., Hartung, J. B., and Gault, D. E.: 1971,Earth Planetary Sci. Letters 10, 381–386.
Kieffer, S. W. and Kamb, B.: 1972,Rev. Geophys., in press.
Kreiger, F. J.: 1967, ‘The Thermodynamics of the Magnesium Silicate/Magnesium - Silicon Oxygen Vapor System’, Rand Corp. Memorandum RM-5337-PR, April.
Lunar Sample Preliminary Examination Team: 1969,Science 165, 1211–1227.
Lunar Sample Preliminary Examination Team: 1970,Science 167, 1325–1339.
Lunar Sample Preliminary Examination Team: 1971,Science 173, 681–694.
Lunar Sample Preliminary Examination Team: 1972,Science, in press.
Mayer, S. E. and Mayer, M. G.: 1940,Statistical Mechanics, John Wiley, New York.
McQueen, R. G., Marsh, S. P., and Fritz, J. N.: 1967,J. Geophys. Res. 72, 4999–5036.
McQueen, R. G., Fritz, J. N., and Marsh, S. P.: 1963,J. Geophys. Res. 68, 2319–2322.
Morgan, J. W., Laul, J. C., Ganapathy, R., and Anders, E.: 1971,Science 172, 556–557.
Naumann, R. J.: 1971,J. Appl. Phys. 42, 4945–4954.
Porter, R. F., Chupka, W. A., and Inghram, M. G.: 1955,J. Chem. Phys. 23, 216–217.
Rice, M. H., McQueen, R. G., and Walsh, J. M.: 1958, inSolid State Physics,6, (ed. by F. Seitz and D. Turnbull), pp. 1–63, Academic Press, New York.
Robie, R. A. and Waldbaum, D. R.: 1968,Geol. Survey Bull. 1259, 265 pp.
Shoemaker, E. M., Hait, M. H., Swann, G. A., Schleicher, D. L., Schaber, G. G., Sutton, R. L., and Dahlem, D. H.: 1970,Geochim. Cosmochim. Acta Suppl. I, Proc. of the Apollo 11 Lunar Science Conf.,3, pp. 2399–2412.
Shoemaker, E. M.: 1970,Publ. Inst. Invest. Geol. 24, Universidad Barcelono, in press.
Swalin, R. A.: 1962,Thermodynamics of Solids, John Wiley, New York, 343 pp.
Trunin, R. F., Simakov, G. V., Podurets, M. A., Moiseyev, B. N., and Popov, L. V.: 1971a,Izv. Earth Physics, No. 1, pp. 13–20.
Trunin, R. F., Simakov, G. V., and Podurets, M. A.: 1971b,Izv. Earth Physics, No. 2, pp. 33–39.
Vedder, J. F.: 1971,Earth Planetary Sci. Letters 11, 29–296.
Wackerle, J.: 1962,J. Appl. Phys. 33, 922–937.
Walsh, J. M., Johnson, W. E., Dienes, J. K., Tillotson, J. H., and Yates, D. R.: 1964, ‘Summary Report on the Theory of Hypervelocity Impact’, General Atomic Report GA-5119, 66 pp.
Young, D. A. and Adler, B. J.: 1971,Phys. Rev. 3, 364–669.
Zeldovich, Y. B. and Raizer, Y. P.: 1966,Physics of Shock Waves and High Temperature Phenomena, Academic Press, New York, Vol. II.
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Contribution number 210, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, Calif. 91109, U.S.A.