Ts-MARE VOLCANISM AND BASALT PETROGENESIS : " ASTOUNDING FUNDAMENTAL CONCEPTS ( AFC ) "-DEVELOPED OVER THE LAST FIFTEEN YEARS
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A model for small‐impact erosion applied to the lunar surface
A model for erosion of the lunar surface by impact of small projectiles is developed that provides an analytic representation of the change of crater shape as a function of time. The model is applied to the erosion of craters approximately 1 meter to 1 km in diameter. The lifetime of a crater in this size range, which is steadily eroded by impact, is approximately proportional to its radius. The model predicts the observed steady-state size frequency distribution of small lunar craters and the dependence of this distribution on the crater-production curve.
A simplified mathematical model for lunar crater erosion
Meteoritic bombardment of the lunar surface results in an erosion process that tends to soften the topography. A simplified mathematical model illustrating the erosion of lunar craters is presented. The model takes into consideration the angular distribution of impacting meteorites and ejecta and the topography and mechanical properties of the lunar surface. Calculations indicate that craters 1, 10, and 100 meters in diameter disappear almost completely after 107, 108, and 109 years, respectively. The results of this study suggest that the minimum depth of debris in the maria is a few meters. Processes other than erosion due to small meteoritic masses, such as volcanic activity, isostatic compensation, and the infrequent impact of a large meteoroid, would be necessary to significantly modify the relief of craters larger than a kilometer in diameter.