Skip to main content

Compaction by impact of unconsolidated lunar fines

Abstract

New Hugoniot and release adiabate data for 1.8 g cm−3 lunar fines (sample, 70051) in the ç2 to ç70 kbar range demonstrate that upon shock compression intrinsic crystal density (ç3.1 g cm−3) is achieved undershock stresses of 15 to 20 kbar. Release adiabate determinations indicate that measurable irreversible compaction occurs upon achieving shock pressures above ç4 kbar. For shocks in the ç7 to 15 kbar range, the inferred,post-shock, specific volumes observed decrease nearly linearly with increasing peak shock pressures. Upon shocking to ç15 kbar the post-shock density is approximately that of the intrinsic minerals. If the present data for sample 70051 are taken to be representative of the response to impact of unconsolidated regolith material on the Moon, it is inferred that the formation of appreciable quantities of soil breccia can be associated with the impact of meteoroids or ejecta at speeds of as low as ç1 km s−1.

This is a preview of subscription content, access via your institution.

References

  1. Ahrens, T. J. and Cole, D. M.: 1974,Proc. Fifth Lunar Sci. Conf., Geochim. Cosmochim. Acta, Suppl. 5,3, 2335–2344.

    Google Scholar 

  2. Ahrens, T. J. and Gregson, V. G.: 1964,J. Geophys.Res. 69, 4389–4874.

    Google Scholar 

  3. Ahrens, T. J., Lower, J. H., and Lagus, P. L.: 1971,J. Geophys. Res. 76, 518–530.

    Google Scholar 

  4. Ahrens, T. J., Petersen, C. F., and Rosenberg, T. J.: 1969,J. Geophys. Res. 74, 2727–2746.

    Google Scholar 

  5. Baldwin, R. B.: 1963,The Measure of the Moon, University of Chicago Press, Chicago.

    Google Scholar 

  6. Christie, J. M., Griggs, D. T., Heuer, A. H., Nord, G. L., Jr., Radcliffe, S. V., Lally, J.S., and Fisher, R. M.: 1973,Proc. Fourth Lunar Sci. Conf., Geochim. Cosmochim. Acta, Suppl. 4,1, 365–832.

    Google Scholar 

  7. Gault, D. E. and Heitowit, E. D.: 1963,Proc. Sixth Hypervelocity Impact Symposium, Cleveland, Ohio, Vol. 2, pp. 419-456, (unpublished).

  8. Gault, D. E., Hörz, F., Brownlee, D. E., and Hartung, J. B.: 1974,Proc. Fifth Lunar Sci. Conf., Geochim. Cosmochim. Acta, Suppl. 5,3, 2365–2386.

    Google Scholar 

  9. Hartmann, W. K. and Wood, C. A.: 1971,The Moon 3, 3–78.

    Google Scholar 

  10. Hörz, F.: 1969,Contr. Mineral. Petrol. 21, 365–377.

    Google Scholar 

  11. Kieffer, S. W.: 1975,The Moon, in press.

  12. LSPET (Lunar Sample Preliminary Examination Team): 1972,Apollo 15 Preliminary Science Report, NASA SP-289, pp. 6-1-25, U. S. Government Printing Office.

  13. LSPET (Lunar Sample Preliminary Examination Team): 1973,Apollo 17 Preliminary Science Report, NASA SP-300, pp. 7-1-46 U.S. Government Printing Office.

  14. McGetchin, T. R., Settle M., and Head, J. W.: 1973,Earth Planetary Sci. Letters 20, 226–236.

    Google Scholar 

  15. McQueen, R. G., Marsh, S. P., Taylor, J. W., Fritz, J. N., and Carter, W. J.: 1970, in R. Kinslow (ed.),High-Velocity Impact Phenomena, pp. 293-417, Academic Press.

  16. Moore, H. J.: 1966,U.S.G.S. Report, November, pp. 79-106.

  17. Moore, H. J.: 1975,U.S.G.S. Professional Paper (to be published).

  18. Moore, H. J., Gault, D. E., and Lugn, R. V.: 1963,Trans. Mining Engineers, pp. 258-262.

  19. O'Keefe, J. D. and Ahrens, T. J.: 1975,Proc. Sixth Lunar Sci. Conf., (in press).

  20. Pike, P. J.: 1974,Earth Planetary Sci. Letters 23, 265–274.

    Google Scholar 

  21. Schmitt, H. H. and Cernan, E. A.: 1973,Apollo 17 Preliminary Science Report, NASA SP-300, pp. 5-1-21.

  22. Tera, F., Papanastassiou, D. A., and Wasserburg, G. J.: 1974,Earth Planetary Sci. Letters 22, 1–21.

    Google Scholar 

Download references

Author information

Affiliations

Authors

Additional information

Contribution No. 2626, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, Calif., U.S.A.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Ahrens, T.J. Compaction by impact of unconsolidated lunar fines. The Moon 14, 291–299 (1975). https://doi.org/10.1007/BF00565328

Download citation

Keywords

  • Compaction
  • Breccia
  • Specific Volume
  • Appreciable Quantity
  • Shock Compression