DETAILED GEOLOGIC MAPPING OF VENUS' CRUSTAL PLATEAUS AND IMPLICATIONS FOR PLATEAU FORMATION
Each of these hypotheses makes different predictions for CP surface history. We present detailed geologic maps of three CPs, Alpha, Ovda, and Tellus Regiones in order to evaluate current hypotheses. Mapping employs Magellan data including high-resolution (100m/pixel) synthetic aperture radar (SAR) data (left-, right- and stereo-look), altimetry, and synthetic stereo images. Mapping to date reveals widespread layer extension and contraction, and intricate surface flooding across each CP. Contractional and extensional structures occur in multiple λs. Short-λ structures dominantly predate long-λ structures. Flooding is prominent throughout structurally defined lows, including many local lows preserved along the crests of long-λ folds. These observations indicate that low viscosity fluid (likely magma) was able to leak to the surface across huge expanses of each CP during surface deformation, implying that CP deformation likely occurred under extremely high temperature conditions. High temperatures would also be consistent with the nature of tectonic structures. These observations challenge the downwelling and plume hypotheses, but might be accommodated within the lava pond hypothesis.