Could crustal churning power Venus volcanoes

Could crustal churning power Venus volcanoes
by Clarence Oxford
Los Angeles CA (SPX) Apr 01, 2025

Venus, a searing world cloaked in dense clouds and blanketed by volcanic structures, may possess a geologically dynamic crust far more active than previously believed. New findings from scientists at Washington University in St. Louis suggest that the planet's outer layer could be undergoing convection, a process rarely associated with planetary crusts, offering fresh insight into the planet's remarkable volcanic landscape.

"Nobody had really considered the possibility of convection in the crust of Venus before," said Slava Solomatov, professor of earth, environmental and planetary sciences at WashU. "Our calculations suggest that convection is possible and perhaps likely. If true, it gives us new insight into the evolution of the planet."

Published in Physics of Earth and Planetary Interiors, the study was co-authored by postdoctoral fellow Chhavi Jain. The research hinges on fluid dynamic models that the team developed to evaluate whether Venus' crust, given its unique thermal and structural conditions, could support convective motion.

Convection, familiar from Earth's mantle, involves hotter material rising while cooler matter sinks, setting up a self-sustaining flow. This circulation helps power Earth's tectonic activity. However, Earth's crust is generally too thin and cold to permit such behavior. On Venus, the crust may reach 30 to 90 kilometers in thickness and endure far higher temperatures, potentially making surface-level convection feasible.

Solomatov and Jain's theoretical analysis indicates that Venus' crust could maintain a convective cycle, introducing a previously overlooked mechanism for transporting interior heat to the surface. The implications are significant: this could help explain the abundance of volcanoes and other heat-related features scattered across the planet's terrain.

In contrast, the researchers had earlier concluded that Mercury lacks such convective activity, owing to its diminutive size and extensive cooling over billions of years. Venus, by comparison, remains intensely hot with surface temperatures soaring to 870 degrees Fahrenheit, sustaining the potential for crustal motion.

"Convection in the crust could be a key missing mechanism," Solomatov noted. The phenomenon may also influence the formation and distribution of volcanoes. In 2023, WashU's Paul Byrne compiled a global atlas mapping 85,000 Venusian volcanoes using radar data from NASA's Magellan mission. Solomatov and Byrne are now considering collaborations that would combine surface imaging with theoretical modeling to decode Venus' complex geology.

Future space missions could be pivotal in confirming crustal convection by measuring variations in crust density and temperature. Such variations would manifest as differences in gravity, potentially detectable through high-resolution instruments.

Beyond Venus, Solomatov pointed to Pluto as another compelling case. New Horizons images of Sputnik Planitia revealed patterns suggesting tectonic-like convection in a layer of solid nitrogen ice. "Pluto is probably only the second planetary body in the solar system, other than Earth, where convection that drives tectonics is clearly visible on the surface," Solomatov said. "It's a fascinating system that we still need to figure out."

Research Report:On the possibility of convection in the Venusian crust