Martian cratering. III - Theory of crater obliteration.

Discussion of a theoretical basis for interpretation of Martian crater obliteration. Strong evidence is found that Martian craters are being degraded and obliterated at a rate much faster than on the moon, but much slower than on earth. The theory obviates the need to interpret the diameter distribution in terms of two classes of impacting bodies, as has been done elsewhere. It is suggested that obliteration is caused by filling of the craters, probably by deposition of dust.