[Previous] | [Session 47] | [Next]
N. G. Barlow (N. AZ Univ.), K. M. Block (Fl. Atlantic U.)
Recent analyses of small martian impact craters has raised the question of whether secondary crater production is statistically identical between Mars and the Moon. Because absolute ages of terrain units depend on the extrapolation of the lunar crater chronology curve to Mars, any variations in secondary crater production between the two bodies will lead to large uncertainties in stated ages based on small crater analysis. We are conducting studies of secondary crater production for similar energy impacts on the Moon and Mars. Our initial study has focused on the basaltic plains comprising the lunar mare and the martian volcanic and ridged plains. We have utilized THEMIS and MOC imagery to identify and measure the diameters of secondary craters within six crater radii of six martian impact craters. Using scaling relationships, we have identified craters likely produced by similar energy impacts on the lunar mare and measured their secondary crater fields. The secondary crater data for similar energy impacts on Mars and the Moon are compared using standard crater size-frequency distribution plotting techniques. Very few secondary craters are found within the layered ejecta deposits surrounding martian impact craters, generally found within ~1.5 crater radii of the rim. However, our results indicate that the frequency of secondary crater production is statistically identical for the Moon and Mars between 1.5 and 6 crater radii. We are now analyzing the more distant secondary fields and craters within highlands regions.
[Previous] | [Session 47] | [Next]
Bulletin of the American Astronomical Society, 36 #4
© 2004. The American Astronomical Soceity.