Are there volcanoes on venus




















Planetary geologists refer to these ovular features as coronae. The team was able to identify at least 37 sites that possess the hallmarks of volcanic activity in the past two to three million years. Though the sites do appear to be active, heat flow calculations suggest the coronae are past their peak levels of volcanic activity, according to Forbes.

Further, the surface air pressure on Venus is about 90 times greater than that at sealevel on Earth. These surface conditions have two effects.

Indeed, there is almost no water in the air, either. The clouds are mostly made of sulfuric acid and they are much, much higher than most clouds on the Earth. Thus, neither wind nor rain can really affect the surface on Venus. As a result, volcanic features will look freshly formed for a long time. Second, Venus shows no evidence for plate tectonics.

There are no long, linear volcano chains. There are no clear subduction zones. Although rifts are common, none look like the mid-ocean ridges on Earth. Also, continent-like regions are rare, and show none of the jigsaw fits seen on Earth.

Thus, where volcanism on Earth mostly marks plate boundaries and plate movements, volcanism on Venus is much more regional and much less organized. Third, volcanism on Venus shows fewer eruptive styles than on the Earth. Scientists have known for some time that Venus has a younger surface than planets like Mars and Mercury, which have cold interiors. Evidence of a warm interior and geologic activity dots the surface of the planet in the form of ring-like structures known as coronae, which form when plumes of hot material deep inside the planet rise through the mantle layer and crust.

This is similar to the way mantle plumes formed the volcanic Hawaiian Islands. But it was thought that the coronae on Venus were probably signs of ancient activity, and that Venus had cooled enough to slow geological activity in the planet's interior and harden the crust so much that any warm material from deep inside would not be able to puncture through.

In addition, the exact processes by which mantle plumes formed coronae on Venus and the reasons for variation among coronae have been matters for debate.

In the new study, the researchers used numerical models of thermo-mechanic activity beneath the surface of Venus to create high-resolution, 3D simulations of coronae formation. Their simulations provide a more detailed view of the process than ever before. The team was then able to match those features to those observed on the surface of Venus, revealing that some of the variation in coronae across the planet represents different stages of geological development.

The study provides the first evidence that coronae on Venus are still evolving, indicating that the interior of the planet is still churning. The active coronae on Venus are clustered in a handful of locations, which suggests areas where the planet is most active, providing clues to the workings of the planet's interior. These results may help identify target areas where geologic instruments should be placed on future missions to Venus, such as Europe's EnVision that is scheduled to launch in



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