A surprising geological process, identified as convection, may offer explanations for numerous volcanic formations and other topographical features observed on Venus.
Artist’s impression of a volcano erupting on Venus. Image credit: ESA / AOES Medialab.
Professor Slava Solomatov of Washington University in St. Louis noted that the proposition of crustal convection on Venus had not been extensively explored previously.
“Our computational models indicate that convection is not only feasible but potentially prevalent. If this hypothesis holds true, it would significantly enhance our understanding of the planet’s developmental trajectory,” he stated.
Convection is a phenomenon characterized by the upward movement of heated matter and the downward displacement of cooler substances, establishing a continuous circulatory system.
On Earth, the energetic forces driving plate tectonics originate from convection currents deep within the planetary mantle.
The Earth’s crust, which measures approximately 40 km in thickness over continental landmasses and 6 km beneath oceanic expanses, is considered too insubstantial and lacking in warmth to sustain convective activity.
However, Professor Solomatov and his collaborator, Dr. Chhavi Jain from Washington University in St. Louis, theorized that Venus’s crust might possess the requisite thickness (estimated between 30-90 km, varying by region), thermal energy, and rock composition to maintain such a circulatory mechanism.
To validate this conjecture, the researchers employed novel fluid dynamics theories developed within their research group.
Their analyses concluded that the crust of Venus could indeed support convection, presenting an entirely novel perspective on the geological dynamics of its surface.
In the year 2024, the same analytical methodology was utilized to ascertain that convection is unlikely to occur within Mercury’s mantle, attributed to the planet’s diminutive size and substantial cooling since its formation 4.5 billion years ago.
Conversely, Venus exhibits considerable thermal energy, both internally and in its atmospheric conditions. Surface temperatures can reach 465 degrees Celsius (870 degrees Fahrenheit), and its volcanic activity and other surface features unequivocally point to widespread melting.
A long-standing enigma for scientists has been the mechanism by which heat from the planet’s interior is transported to its surface.
Professor Solomatov proposed that “Convection occurring within the crust could represent a critical, previously overlooked pathway for heat transfer.”
He also suggested that “Proximity convection to the surface may also exert influence on the classification and geographical distribution of volcanic features on Venus.”
The research team anticipates that future exploratory missions to Venus will yield more precise data concerning the density and temperature profiles within its crust.
Should convection be actively occurring as hypothesized, certain crustal regions would demonstrably exhibit higher temperatures and lower densities compared to others, distinctions that could be discernible through sophisticated gravitational measurements.
However, an even more captivating subject of investigation might be Pluto, the frigid dwarf planet located at the distant periphery of our Solar System.
Imagery acquired by NASA’s New Horizons spacecraft has revealed striking polygonal formations in Pluto’s Sputnik Planitia region, bearing a resemblance to terrestrial plate boundaries.
These geometric patterns are understood to be the result of slow convection currents within a 4 km deep layer of solid nitrogen ice.
Professor Solomatov remarked, “Pluto appears to be only the second celestial body within the Solar System, besides Earth, where surface convection demonstrably drives tectonic processes,”.
He added, “It presents a compelling system that still requires thorough elucidation.”
The scholarly findings were disseminated in the periodical Physics of Earth and Planetary Interiors.
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Viatcheslav S. Solomatov & Chhavi Jain. 2025. On the possibility of convection in the Venusian crust. Physics of the Earth and Planetary Interiors 361: 107332; doi: 10.1016/j.pepi.2025.107332
