Using Tessera Terrain to Investigate Fold Belt Topography in Ovda Regio, Venus
Folds from the tessera terrain of Ovda Regio, Venus have been interpreted as both thrust folds and buckle folds. Comparisons of slope data from this terrain suggest that Venus exhibits a range of fold shapes from symmetrical to asymmetrical. Erosion could be masking the true topography of the features; however regolith-forming processes are minor on Venus. Detachment variation or fault duplexing can produce symmetrical and asymmetrical folds in the same location but multiple weak detachments are not expected for the plateaus, making duplexing unlikely. Symmetry variance could result from overstrained buckle folds becoming asymmetric. The rheology of the plateaus is not known but is likely contributing to the varied symmetry of the surface. The end-member models used for comparison may be unrealistic analogs because they have sedimentary compositions and sharp mechanical detachments rather than being thermally activated. The folding of oceanic crust may be a more realistic analog.