Table 1. Depth-to-Diameter Ratios of Different Classes of Impact Craters

Impact Crater Class									d/D
All McMurdo secondary craters								0.020
McMurdo secondary craters on slopes less than the mean slope				0.014
McMurdo secondary craters on slopes of greater than the mean slope			0.032
“Field II” secondary craters								0.010
SPLD primary craters [Koutnik et al., 2002]						0.015
Expected initial secondary crater d/D [Pike and Wilhelms, 1978; 
McEwen et al., submitted manuscript, 2004]						0.11