Plate flexure and the strength of Venusian lithosphere.

Venus shows a wide range of surface morphological features that can be attributed to plate flexure, including rift flank uplifts, outer topographic rises, and trench-like depressions. Flexural modelling suggest that the elastic plate thickness, T_e, required to explain these features is in the range 10-30 km. These values are smaller than continental T_e estimates, but are similar to oceanic T_e estimates. This essay reviews the relative role of plate flexure and mantle dynamics in contributing to the topography of Venus, and explores why the Venusian lithosphere, which has a surface temperature of some 450 ^oC, might be as strong as parts of the Earth's lithosphere.

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