Venus, Earth’s ‘twin planet,’ presents clear contrasts in terms of surface conditions, atmospheric chemistry, and tectonic state. Understanding the interior processes shaping Venus’ surface is a fundamental goal for planetary sciences.

The surface of Earth is continually renewed by the constant shifting and recycling of massive sections of crust, called tectonic plates, that float atop a viscous interior.

Venus doesn’t have tectonic plates, but its surface is still being deformed by molten material from below.

Seeking to better understand the underlying processes driving these deformations, the researchers studied a type of feature called a corona.

Ranging in size from dozens to hundreds of km across, a corona is most often thought to be the location where a plume of hot, buoyant material from the planet’s mantle rises, pushing against the lithosphere above.

These structures are usually oval, with a concentric fracture system surrounding them.

According to scientists, hundreds of coronae are known to exist on Venus.

Using archival data from NASA’s Magellan mission, Dr. Gael Cascioli from the University of Maryland and NASA’s Goddard Space Flight Center and his colleagues found signs of activity at or beneath the surface shaping many of Venus’ coronae.

“Coronae are not found on Earth today; however, they may have existed when our planet was young and before plate tectonics had been established,” said Dr. Cascioli, lead author of a paper published in the journal Science Advances.

“By combining gravity and topography data, this research has provided a new and important insight into the possible subsurface processes currently shaping the surface of Venus.”

Launched in 1989, Magellan used its radar system to see through Venus’ thick atmosphere and map the topography of its mountains and plains.

Of the geological features the spacecraft mapped, coronae were perhaps the most enigmatic: It wasn’t clear how they formed.

In the years since, planetary researchers have found many coronae in locations where the planet’s lithosphere is thin and heat flow is high.

“Coronae are abundant on Venus. They are very large features, and people have proposed different theories over the years as to how they formed,” said Dr. Anna Gülcher, a researcher at the University of Bern.

“The most exciting thing for our study is that we can now say there are most likely various and ongoing active processes driving their formation.”

“We believe these same processes may have occurred early in Earth’s history.”

The researchers developed sophisticated 3D geodynamic models that demonstrate various formation scenarios for plume-induced coronae and compared them with the combined gravity and topography data from Magellan.

The gravity data proved crucial in helping the researchers detect less dense, hot, and buoyant plumes under the surface — information that couldn’t be discerned from topography data alone.

Of the 75 coronae studied, 52 appear to have buoyant mantle material beneath them that is likely driving tectonic processes.

One key process is subduction: on Earth, it happens when the edge of one tectonic plate is driven beneath the adjacent plate.

Friction between the plates can generate earthquakes, and as the old rocky material dives into the hot mantle, the rock melts and is recycled back to the surface via volcanic vents.

On Venus, a different kind of subduction is thought to occur around the perimeter of some coronae.

In this scenario, as a buoyant plume of hot rock in the mantle pushes upward into the lithosphere, surface material rises and spreads outward, colliding with surrounding surface material and pushing that material downward into the mantle.

Another tectonic process known as lithospheric dripping could also be present, where dense accumulations of comparatively cool material sink from the lithosphere into the hot mantle.

The researchers also identify several places where a third process may be taking place: a plume of molten rock beneath a thicker part of the lithosphere potentially drives volcanism above it.

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Gael Cascioli et al. 2025. A spectrum of tectonic processes at coronae on Venus revealed by gravity and topography. Science Advances 11 (20); doi: 10.1126/sciadv.adt5932