Venus is Earth’s twin in size and radiogenic heat budget, yet it remains unclear how Venus loses its heat absent plate tectonics. Most Venusian stagnant-lid models predict a thick lithosphere with heat flow about half that of Earth’s mobile-lid regime. Here we estimate elastic lithospheric thickness at 75 locations on Venus using topographic flexure at 65 coronae—quasi-circular volcano-tectonic features—determined from Magellan altimetry data. We find an average thickness at coronae of 11 ± 7 km. This implies an average heat flow of 101 ± 88 mW m−2, higher than Earth’ s average but similar to terrestrial values in actively extending areas. For some locations, such as the Parga Chasma rift zone, we estimate heat flow exceeding 75 mW m−2. Combined with a low-resolution map of global elastic thickness, this suggests that coronae typically form on thin lithosphere, instead of locally thinning the lithosphere via plume heating, and that most regions of low elastic thickness are best explained by high heat flow rather than crustal compensation. Our analysis identifies likely areas of active extension and suggests that Venus has Earth-like lithospheric thickness and global heat flow ranges. Together with the planet’s geologic history, our findings support a squishy-lid convective regime that relies on plumes, intrusive magmatism and delamination to increase heat flow.
ASJC Scopus subject areas
- General Earth and Planetary Sciences