Tectonic effects of climate change on Venus

Venusian plains regions are commonly crossed by small-strain deformation fe atures such as wrinkle ridges, polygonal terrains, and gridded terrains. Of these, polygonal terrains are observed to have a relatively uniform spacin g and are widely distributed on plains that formed during global resurfacin g. Models of Venusian climate that assume resurfacing occurred through mass ive volcanic events suggest that surface temperatures could have dramatical ly changed over a billion years, propagating thermal stresses into the surf ace and potentially causing small-strain features. We investigate this hypo thesis by approximating the temperatures predicted by climate models as a s tep function and employ a fixed plate and strength envelope model to predic t the resulting depth of failure and amount of strain. Our calculations ind icate that strains due to temperature changes of 50-100 K, which are favore d for volcanic resurfacing events of 1-10 km thickness, are consistent with the observed spacing of polygonal and gridded terrains as well as some wri nkle ridges. The global nature of the climate change event is consistent wi th the global distribution and uniformity of such features and implies that such terrains may be a global stratigraphic marker.