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==Resurfacing hypotheses==
The global distribution of impact craters that was discovered by the Magellan mission to Venus has led to numerous theories on Venusian resurfacing. Phillips et al. (1992) developed two conceptual end-member resurfacing models that describe the distribution of impact craters. The first end-member model suggests that a spatially random distribution of craters can be maintained by having short-duration resurfacing events of large spatial area that occur in random locations with long intervening time intervals. A special case of this end-member would be global resurfacing events; for this case one would be unable to tell from the current surface whether the last global event was part of a recurring cycle or a singular event in the planet's history. The other end-member is that resurfacing events that wipe out craters are of small spatial area, randomly
This is effectively a [[uniformitarian]] hypothesis as it assumes that geologic activity is occurring everywhere at similar rates. Global events that periodically resurface nearly the entire planet will leave a crater-free surface: craters then occur and aren't subsequently modified until the next global event.<ref name="Herrick and Rumpf, 2011">{{cite journal|last=Herrick|first=R. R.|author2=M. E. Rumpf|title=Postimpact modification by volcanic or tectonic processes as the rule, not the exception, for Venusian craters|journal=Journal of Geophysical Research|date=2011|volume=116|issue=E2|pages=2004|bibcode=2011JGRE..116.2004H|doi=10.1029/2010JE003722|doi-access=free}}</ref> Resurfacing events occurring frequently everywhere will produce a surface with many craters in the process of being resurfaced.<ref name="Herrick and Rumpf, 2011"/> Thus, the end-members can be distinguished by observing the extent to which the craters have experienced some degree of tectonic deformation or volcanic flooding.
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