Lithospheric Structure of Venusian Crustal Plateaus

Crustal plateaus are Venusian highlands characterized by tectonized terrains. It is commonly interpreted that their topography isostatically supported and they represent fossils of an extinct tectonic regime. Using gravity we perform a comprehensive investigation the lithospheric structure six crustal plateaus. We computed admittance (gravity to wavelength-dependent ratio) for each region compared them modeled admittances. Three compensation scenarios were tested: Airy isostasy, surface-loading flexural model, model with surface subsurface loads. Our results show most thickening addition mantle support component not necessary at investigated wavelengths. The elastic thickness was constrained be less than 35 km best-fitting average 15 km, confirming these regions consistent isostatic ranges from 34 if in this implies global Venus about 20 km. Phoebe Regio sole exception our analysis thicknesses compatible other obtained only when buoyant layer included. Heat flow estimations indicate formed under higher heat conditions current could have caused localized melting. Present-day predictions suggest eclogitization occur where crust thickest.