Virgil L. Sharpton, 1992. "Evidence from Magellan for unexpectedly deep complex craters on Venus", Large Meteorite Impacts and Planetary Evolution, B. O. Dressier, R.A.F. Grieve, V. L. Sharpton
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The inverse gravity (1/g) scaling trend for complex crater depths and the shallow depths reported from terrestrial impact structures led to the general expectation that depths of Venusian craters would be Earth-like and considerably shallower than those of the smaller planets like Mars. Pioneer Venus and Venera 15/16 radar observations seemed to indicate very shallow craters as expected; however, the present analysis shows that any crater depth information reported from these missions should be considered only as minimum bounds. I present new estimates of complex crater depths on Venus derived from cross-track distortions in Magellan radar images that reveal that the freshest craters approach those on Mars in terms of their depth/diameter characteristics. Consequently, strict 1/g scaling does not seem to hold for Venus, indicating that other planetary properties, such as the presence of an atmosphere, may have an overwhelming effect on crater depth. Craters with dark floors are distinctly shallower than fresh Venusian craters, indicating their originally bright crater floors probably have been covered by relatively smooth volcanic deposits. Topographic profiles across four complex craters reveal that these structures have rim heights accounting for as much as 50% of the total crater depth. Because there are no complex craters on Earth which have retained their rim crests, reported depths of terrestrial structures may be underestimated by a comparable amount due to rim removal alone. Venusian complex craters may be more useful for reconstructing the original appearance of eroded craters on Earth than either the lunar craters or the simple 1/g scaling previously used.