A recently published study describes how Mars may be more volcanically active than previously thought. An area of magma almost 4,000 kilometers wide appears to be pressing on the surface from below.
It has long been believed that Mars is geologically “dead,” meaning that its interior has cooled and that the planet has no volcanic processes. This is due to the lack of shifting tectonic plates like we have on Earth. The lack of a strong magnetic field around Mars has also been seen as evidence that nothing is happening below the surface.
However, a number of observations have questioned the idea of a completely dead planet. Satellite photos indicate a volcanic eruption that must have occurred only 50,000 years ago. A space rock from Mars that managed to reach Earth shows signs of activity in the planet’s mantle about half a billion years ago.
In addition, the Mars Insight spacecraft has been making seismic measurements on the Red Planet since 2018 and has been able to detect “Marsquakes” attributable to volcanic activity. Another observation that is addressed in the new Education – as published in Nature Astronomy – is that an area called Elysium Planitia has high local gravity.
The study looked for a model that matched the observational data
According to the researchers’ analyses, data collected on topography, gravity, geology and seismic activity are consistent with a mantle plume under the surface of Mars. A mantle plume is a large collection of hot, liquid rock that penetrates the mantle and reaches the surface of a planet. These can, for example, be the basis of volcanic eruptions and earthquakes in the ground.
An illustration of what the interior of Mars might look like. Photos: Adrien Broquet and Audrey Lasbordes
To match the various observations, the mantle plume would need to be at least 3,500 kilometers across. According to the researchers, this would mean that Mars is the third planet – besides Earth and Venus – in the solar system with this type of volcanic activity.
– The fact that Mars today has an active mantle plume is a paradigm shift for our understanding of the planet’s geological evolution, similar to the analyzes of seismic measurements by the Apollo program that showed the moon’s core is liquid, says Adrien Broquet, postdoctoral research assistant and study co-author in a Press release.
The researchers also say the discovery could play a role in determining whether or not there is life on the planet. For example, there are signs that there was previously water in the region which is now being studied. It’s possible that the heat from volcanic activity could melt ice and create underground rivers where life could exist, according to the study.
