Encyclopedia of Lunar Science

Living Edition
| Editors: Brian Cudnik

Lunar Crater Ejecta

Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-05546-6_15-1

Impact ejecta deposits are composed of materials produced and ejected by the impact cratering process. Fractured target rocks that are ejected become ejecta blanket breccias, and target materials that are melted by the impact process become impact melt deposits (typically deposited as flows, ponds, and veneers) located on top of and among the ejecta blanket breccias. A more technical definition of crater ejecta is any material from the target body, regardless of their physical state, that is transported beyond the rim of the transient crater cavity formed directly by the cratering flow field (e.g., Melosh 1989; Osinski et al. 2011).

Formation of Ejecta Blankets

Much of what is known about the ejection process has been determined from high-speed impact experiments and hydrocode modeling of the impact process. Additional information has been inferred from observations of buried nuclear bomb explosion tests during the early 1960s (experiments as part of Operation Plowshare; see Roddy et...

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  1. Anderson JLB, Schultz PH, Heineck JT (2003) Asymmetry of ejecta flow during oblique impacts using three-dimensional particle image velocimetry. J Geophys Res 108. doi: 10.1029/2003JE002075
  2. Atwood-Stone C, Bray VJ, McEwen AS (2016) A new study of crater concentric ridges on the moon. Icarus 273:196–204.  http://dx.doi.org/10.1016/j.icarus.2016.03.012. ISSN 0019-1035ADSCrossRefGoogle Scholar
  3. Bell JF, Hawke BR (1984) Lunar dark-haloed impact craters: origins and implications for early Mare volcanism. J Geophys Res 89(B8):6899–6910ADSCrossRefGoogle Scholar
  4. Bray VJ, Tornabene LL, Keszthelyi LP, McEwen AS, Hawke BR, Giguere TA, Kattenhorn SA, Garry WB, Rizk B, Caudill CM, Gaddis LR, van der Bogert CH (2010) New insight into lunar impact melt mobility from the LRO camera. Geophys Res Lett 37. https://doi.org/10.1029/2010GL044666 10.1029/2010GL044666
  5. Chapman CR, McKinnon WB (1986) Cratering of planetary satellites. In: Burns JA, Matthews MS (eds) Satellites. University of Arizona Press, Tucson, pp 492–580Google Scholar
  6. Cintala MJ, Berthoud L, Horz F (1999) Ejection-velocity distributions from impacts into coarse-grained sand. Meteorit Planet Sci 34:605–623ADSCrossRefGoogle Scholar
  7. Dence MR (1968) Shock zoning at Canadian craters: petrography and structural implications. In: French BM, Short NM (eds) Shock metamorphism of natural materials. Mono Book Corp., Baltimore, pp 169–184Google Scholar
  8. Denevi BW et al (2012) Physical constraints on impact melt properties from lunar reconnaissance orbiter camera images. Icarus 219(2):665–675ADSCrossRefGoogle Scholar
  9. El-Baz F (1972) King crater and its environs. In: Apollo 16 preliminary science report, NASA spec. publ., NASA SP-315, 29-62–29-70Google Scholar
  10. French BM (1998) Traces of catastrophe: a handbook of shock-metamorphic effects in terrestrial meteorite impact structures. LPI contribution no. 954. Lunar and Planetary Institute, Houston, p 120Google Scholar
  11. Gault DE, Wedekind JA (1978) Experimental studies of oblique impacts. Proc Lunar Planet Sci Conf 9:3843–3875ADSGoogle Scholar
  12. Ghent RR, Gupta V, Campbell BA, Ferguson SA, Brown JCW, Fergason RL, Carter LM (2010) Generation and emplacement of fine-grained ejecta in planetary impacts. Icarus 209:818–835ADSCrossRefGoogle Scholar
  13. Ghent RR, Carter LM, Bandfield JL, Tai Udovicic CJ, Campbell BA (2016) Lunar crater ejecta: physical properties revealed by radar and thermal infrared observations. Icarus 273:182–195.  http://dx.doi.org/10.1016/j.icarus.2015.12.014. ISSN 0019-1035ADSCrossRefGoogle Scholar
  14. Hawke BR, Head JW(1977) Impact melt on lunar crater rims. In: Roddy DJ, Pepin RO, Merrill RB (eds) Impact and explosion cratering. Pergamon Press, pp 815–841Google Scholar
  15. Hawke BR, Blewett DT, Lucey PG, Peterson CA, Bell JF, Campbell BA, Robinson MS (1999) The composition and origin of selected lunar crater rays workshop on new views of the moon II: Understanding the moon through the integration of diverse datasets, 8035Google Scholar
  16. Hawke BR, Blewett DT, Lucey PG, Smith GA, Bell JF III, Campbell BA, Robinson MS (2004) The origin of lunar crater rays. Icarus 170(1):1–16.  dx.doi.org/10.1016/j.icarus.2004.02.013. ISSN 0019-1035ADSCrossRefGoogle Scholar
  17. Heiken GH, Vaniman DT, French BM, (1991) Lunar Sourcebook: A User’s Guide to the Moon; Cambridge University Press, London, UKGoogle Scholar
  18. Hiesinger H, Head JW New views of lunar geoscience: an introduction and overview. Rev Mineral Geochem 60(1):1–81.  https://doi.org/10.2138/rmg.2006.60.1
  19. Housen KR, Holsapple KA (2011) Ejecta from impact craters. Icarus 211:856–875ADSCrossRefGoogle Scholar
  20. Howard KA (1974) Fresh lunar impact craters: review of variations with size. In: Lunar science conference, 5th, Houston, 18–22 March 1974, Proceedings, vol 1 (A75–39540 19–91). Pergamon Press, New York, pp 61–69. NASA-supported researchGoogle Scholar
  21. Howard KA, Wilshire HG (1975) Flows of impact melt at lunar craters. J Res US Geol Surv 3(2):237–251Google Scholar
  22. Krüger T, van der Bogert CH, Hiesinger H (2016) Geomorphologic mapping of the lunar crater Tycho and its impact melt deposits. Icarus 273:164–181.  http://dx.doi.org/10.1016/j.icarus.2016.02.018. ISSN 0019-1035ADSCrossRefGoogle Scholar
  23. McEwen AS, Gaddis LR, Neukum G, Hoffman H, Pieters CM, Head JW (1993) Galileo observations of post-Imbrium craters during the first earth–moon flyby. J Geophys Res 98(1993):17207–17231ADSCrossRefGoogle Scholar
  24. McGetchin TR, Settle M, Head W (1973) Radial thickness variation in impact crater ejecta: implication for lunar basin deposits, earth planet. Sci Lett 20:226–236Google Scholar
  25. Melosh HJ (1989) Impact cratering: a geologic perspective. Oxford Univ. Press, New York, pp 245Google Scholar
  26. Neish CD, Madden J, Carter LM, Hawke BR, Giguere T, Bray VJ, Osinski GR, Cahill JTS (2014) Global distribution of lunar impact melt flows. Icarus 239:105–117.  http://dx.doi.org/10.1016/j.icarus.2014.05.049. ISSN 0019-1035ADSCrossRefGoogle Scholar
  27. Oberbeck VR (1971) A mechanism for the production of lunar crater rays. Moon 2:263–278ADSCrossRefGoogle Scholar
  28. Oberbeck VR (1975) The role of ballistic erosion and sedimentation in lunar stratigraphy. Rev Geophys 13:337–362ADSCrossRefGoogle Scholar
  29. Oberbeck VR, Morrison RH (1973) On the formation of the lunar herringbone pattern. In: Proceedings of the lunar science conference, vol 4, p 107Google Scholar
  30. Öhman T, Kramer GY, Kring DA (2014) Characterization of melt and ejecta deposits of Kepler crater from remote sensing data. J Geophys Res Planets 119:1238–1258.  https://doi.org/10.1002/2013JE004501 ADSCrossRefGoogle Scholar
  31. Osinski GR, Tornabene LL, Grieve RAF (2011) Impact ejecta emplacement on terrestrial planets. Earth Planet Sci Lett 310(3–4):167–181.  http://dx.doi.org/10.1016/j.epsl.2011.08.012. ISSN 0012-821XADSCrossRefGoogle Scholar
  32. Pike RJ (1977) Size-dependence in the shape of fresh impact craters on the moon. Paper presented at the symposium on planetary cratering mechanics, Flagstaff, 13–17 Sept 1976Google Scholar
  33. Plescia JB, Cintala MJ (2012) Impact melt in small lunar highland craters. J Geophys Res 117:E00H12. doi: 10.1029/2011je003941 CrossRefGoogle Scholar
  34. Poelchau MH, Kenkmann T, Kring DA (2009) Rim uplift and crater shape in meteor crater: the effects of target heterogeneities and trajectory obliquity. J Geophys Res 114:E01006.  https://doi.org/10.1029/2008JE003235 ADSCrossRefGoogle Scholar
  35. Richardson JE, Melosh HJ, Lisse CM, Carcich B (2007) A ballistics analysis of the deep impact ejecta plume: determining comet Tempel 1’s gravity, mass, and density. Icarus 190:357–390ADSCrossRefGoogle Scholar
  36. Robinson MS, 22 coauthors (2010) Lunar reconnaissance orbiter camera (LROC) instrument overview. Space Sci Rev 150:81–124. doi: 10.1007/s11214-010- 9634-2
  37. Roddy DJ, Pepin RO, Merrill RB (1977) Impact and explosion cratering: planetary and terrestrial implications; proceedings of the symposium on planetary cratering mechanics. Pergamon Press, New York. 1315 pGoogle Scholar
  38. Schultz PH (1976) Moon morphology. University of Texas Press, AustinGoogle Scholar
  39. Sharpton VL (2014) Outcrops on lunar crater rims: implications for rim construction mechanisms, ejecta volumes and excavation depths. J Geophys Res Planets 119:154–168. doi: 10.1002/2013JE004523 ADSCrossRefGoogle Scholar
  40. Shoemaker EM (1963) Interpretation of lunar craters. In: Kopal Z (ed) Physics and astronomy of the Moon. Academic Press, pp 283–359Google Scholar
  41. Shoemaker EM (1970) Origin of fragmental debris on the lunar surface and history of bombardment of the Moon. Presentation at I Seminario de Geologia Lunar, University of Barcelona (Rev. January 1971)Google Scholar
  42. Singer KN, McKinnon WB, Nowicki LT (2013) Secondary craters from large impacts on Europa and Ganymede: Ejecta size–velocity distributions on icy worlds, and the scaling of ejected blocks. Icarus 226(1):865–884. https://doi.org/10.1016/j.icarus.2013.06.034. ISSN 0019–1035Google Scholar
  43. Vickery AM (1986) Size-velocity distribution of large ejecta fragments. Icarus 67:224–236ADSCrossRefGoogle Scholar
  44. Wilhelms DE (1987) The geologic history of the moon. USGS Prof. Paper 1348, United States Geological Survey, Flagstaff, USAGoogle Scholar

Authors and Affiliations

  1. 1.University of Western OntarioLondonCanada

Section editors and affiliations

  • Nicolle E. B. Zellner
    • 1
  1. 1.Department of PhysicsAlbion CollegeAlbionUSA