The Effect of Antecedent Topography on Complex Crater Formation
AbstractImpact craters that form on every planetary body provide a record of
planetary surface evolution. On heavily-cratered surfaces, new craters
that form often overlap older craters, but it is unknown how the
presence of older craters alters impact crater formation. We use
overlapping complex crater pairs on the lunar surface to constrain this
process and find that crater rims are systematically lower where they
intersect antecedent crater basins. However, the rim morphology of the
new crater depends on both the depth of the antecedent crater and the
degree of overlap between the two craters. Our observations suggest that
transient rim collapse is altered by antecedent topography, leading to
circumferential distribution of rim materials in the younger crater.
This study represents the first formalization of the influence of
antecedent topography on rim morphology and provides process insight
into a common impact scenario relevant to the geology of potential
Artemis landing sites.