Researchers at ETH Zurich using new 3D computer models have revealed that Venus’s vast rift valleys, including Ganis, Dali, and Devana Chasmata, may still be geologically active today. The simulations show that broad, steep flanks indicate rapid extension rates of 3 to 10 centimetres per year.
Planetary scientists long viewed Venus as a geologically dormant world, trapped in a runaway greenhouse effect and devoid of the dynamic tectonic plates that constantly reshape Earth. Recent findings challenge that static view, demonstrating that Earth’s toxic neighbor hosts active volcanoes and ongoing tectonic forces. The latest breakthrough comes from a study published in Nature Geoscience by researchers at ETH Zurich, who turned to the planet’s exceptionally well-preserved rift systems to understand its interior.
Why Venus Preserves Tectonic Clues That Earth Erases
Unlike Earth, where relentless rainfall, glacial movement, rivers, and landslides quickly erode fault lines and fill in valleys, Venus offers an unusually durable geological record. The planet has no surface oceans, and while its thick sulphuric acid clouds produce droplets, those evaporate long before reaching the ground. The lack of water means erosion is extremely slow, allowing surface landforms to look crisp millions of years after the tectonic processes that built them have ended.
Venus contains about 40,000 kilometres of mapped rifts covering roughly eight per cent of the planet, frequently crossing broad volcanic rises linked to mantle upwelling. These rift valleys can span up to 10,000 kilometres, resembling terrestrial systems like the African Rift Valley. Because tectonic scars do not get scrubbed away by rivers or weather, geoscientists can examine topography that our own planet would have smoothed over long ago.
Simulating High-Resolution 3D Rifts to Decode Crustal Speed
To determine when these rifts formed and whether they are still moving, lead author Xi Yang and colleagues under the supervision of Professor Taras Gerya used a new computer model to simulate high-resolution, three-dimensional rifts for the first time. Earlier modeling efforts relied on simplified material assumptions and remained mostly two-dimensional.
The simulations reveal that when a rift undergoes rapid extension, the adjacent crust rises and flexes to produce elevated shoulders known as rift flanks. Faster extension paired with a strong crust generates elevation offsets between two and eight kilometres, alongside valleys wider than 120 kilometres. The team’s computer models indicate that these rifts widen at a rate of 3 to 10 centimetres per year.
Comparing Model Predictions With Magellan Probe Data
The central diagnostic tool in the study is time behavior: once tectonic extension stops, wide rift flanks tend to flatten and narrow rapidly due to crustal relaxation. In dry-diabase models, a flank wider than 100 kilometres narrowed to below 90 kilometres within one million years, dropping below 40 kilometres after roughly 15 million years, and disappearing almost entirely after 105 million years. Across all tested scenarios, any rift flank wider than 100 kilometres strongly points to extension that either continues today or ended very recently in geological terms.
- Dali Chasma: Features a median flank width of about 110 kilometres, a steep western side with an offset near five kilometres, and a gentler eastern side.
- Ganis Chasma: Displays a median flank width near 160 kilometres with an offset near four kilometres on its steep western side.
- Devana Chasma: Exceeds 180 kilometres in width, featuring steep sides surrounding a flatter valley floor that aligns with recency models.
These profiles closely resemble strong dry-diabase or mafic-granulite crust stretched at rates of three to ten centimetres per year. The results help us to better assess the tectonic activity on Venus,
says Taras Gerya, Professor of Geodynamics at ETH Zurich.
Implications for Upcoming Space Missions and Exoplanet Detection
The study leaves open two distinct possibilities: rifting on Venus is either actively occurring right now or stopped within the past few tens of millions of years—both of which count as recent developments on a planet where surface erosion crawls. This dynamic interior reshapes how planetary scientists view Earth’s neighbor and provides concrete targets for exploration.
Space agencies are already preparing to return to the planet. ETH geophysics professors Paul Tackley and Taras Gerya are actively participating in the European Space Agency’s EnVision mission, developing instruments for the Venus orbiter scheduled to launch in the early 2030s. By identifying geologically active regions that require particularly close examination, simulations like these will guide future instruments as they probe the planet from its core to its upper atmosphere, ultimately refining how researchers detect and evaluate rocky exoplanets.
