VENUS RESURFACING RATES - CONSTRAINTS PROVIDED BY 3-D MONTE-CARLO SIMULATIONS

The range of surface ages on Venus and the rate of recent volcanism are two major questions that can be addressed through an analysis of Magellan images. We report on a 3-D Monte Carlo resurfacing model that seeks to explain the resurfacing history of Venus by simulating the evolving surface under the competing processes of impact cratering and volcanism. By incorporating the observed size distribution of volcanic forms on Venus, and the assumptions of constant volcanic and impactor fluxes, we seek a solution that is consistent with the observed impact crater population. In the Monte Carlo simulations, a volcanic flux of 0.37 km3/yr, operating for 550 m.y. on initially craterless surfaces, yields surfaces that are statistically similar to Venus'. It is shown that the statistics of the impact cratering record are inconsistent with an equilibrium resurfacing model.