A spectrum of tectonic processes at coronae on Venus revealed by gravity and topography

Abstract

Coronae on Venus are key to understanding the planet’s geodynamics. Their formation is often linked to plume-lithosphere interactions, with some coronae showing signs of plate boundary-like processes such as subduction. However, the low resolution of Venus gravity data limits detailed analysis of these features. Using 3D geodynamic models, we predict gravity signals under various plume-induced corona formation scenarios. Comparing these predictions to observations, we show that combining topography and gravity data is more effective for understanding dynamic processes than using topography alone. Of the 75 resolved coronae, gravity indicates buoyant mantle material beneath 52. We predict a range of plume-lithosphere interactions and activity stages across these coronae. Moreover, we find that the limited resolution of the Magellan gravity field can obscure gravity signatures otherwise indicative of plume activity. The upcoming VERITAS mission will greatly improve gravity resolution, which will resolve 427 coronae, enhancing our understanding of Venus’ lithospheric structure and geodynamics.