3D computer simulations reveal that Venus’ young rift flanks remain tall and steep before gradually flattening as the planet’s crust relaxes.
This hemispheric view of Venus was created using radar observations, including images from NASA’s Magellan spacecraft. Magellan mapped more than 98% of Venus. Gaps in the coverage were filled with observations from the Earth-based Arecibo radar. The composite image was processed to improve contrast, emphasize small surface features, and represent elevation through color coding. NASA’s Magellan spacecraft launched on May 4, 1989, and entered orbit around Venus on August 10, 1990. The mission ended on October 13, 1994, when the spacecraft was directed into Venus’ atmosphere. Image credit: NASA / JPL-Caltech / USGS.
Vast rift valleys on Venus may provide important evidence of the planet’s tectonic history and continuing geological activity. According to new research from ETH Zurich, these features can extend for up to 10,000 km and evolve significantly over time.
“Rift valleys, which indicate tectonic activity, can be vast and resemble those on Earth, such as the African Rift Valley. On Venus, they can span up to 10,000 km,” said ETH Zurich Professor Taras Gerya and colleagues.
The age and formation history of Venusian rifts remain uncertain. However, planetary scientists believe many of these structures formed more than 100 million years ago, making them remnants of an earlier phase in Venus’ geological evolution.
For the new study, the researchers developed a high-resolution, three-dimensional computer model to simulate rift formation on Venus. The model allowed them to reproduce the shape and evolution of Venusian rifts in greater detail than previous simulations.
The results show that broad elevated ridges, known as rift flanks, develop along the edges of rift valleys when the structures are geologically young. These flanks form while the rifts are still actively widening or shortly after tectonic movement has stopped.
According to the simulations, Venusian rifts may widen at rates of approximately 3 to 10 cm per year—faster than earlier estimates suggested.
“The models indicate that broad ridges, known as rift flanks, form along the edges of rift valleys when the rifts are geologically young and either still actively moving or have only recently stopped moving,” the researchers said.
“We also show that the rift flanks tend to flatten rapidly after movement ceases; the older the rift system, the less steep and narrow its flanks.”
Unlike Earth, where erosion gradually wears down mountains and other surface features, Venus’ rift flanks appear to flatten primarily through crustal relaxation. As the underlying crust adjusts after tectonic activity ends, the elevated flanks slowly subside and become less pronounced.
Wide, high rift flanks predicted by the computer simulations are also visible in radar images of Venus captured by NASA’s Magellan spacecraft during its 1990s mission. This agreement between the model and spacecraft observations supports the idea that the shape of Venus’ rifts can reveal their relative age and tectonic history.
Based on the simulations and available observational data, the researchers conclude that Venus may still have a more active interior than previously thought. The findings suggest that some regions of the planet could have experienced relatively recent tectonic activity.
“The results help us to better assess the tectonic activity on Venus,” Professor Gerya said.
“They also could help pinpoint active regions worthy of detailed investigation for future missions to Venus.”
A paper describing the findings was published in the journal Nature Geoscience.
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X. Yang et al. Recent active rifting on Venus revealed by wide rift flank uplifts. Nat. Geosci, published online July 24, 2026; doi: 10.1038/s41561-026-02044-8
Source: www.sci.news