from the I-feel-the-earth-move-under-my-feet dept.
Enormous Mantle Plume Reveals Mars is Still Geologically Active
Enormous Mantle Plume Reveals Mars Is Still Geologically Active - ExtremeTech:
Mars has a reputation as a cold, dead world, but a new study suggests that may be only partially accurate. Researchers from the University of Arizona have analyzed a region that appears to be geologically boring by Martian standards, finding evidence the mantle is pushing upward, causing fissures, swelling, and quakes. This potential mantle plume could mean Mars is much more geologically active than it first appears.
We know that Mars was extremely geologically active in the past, as evidenced by the presence of the tallest volcanoes in the solar system. The planet cooled dramatically between three and four billion years ago, but perhaps it didn't cool as much as believed. The region in question is known as Elysium Planitia, a flat area of the planet's northern lowlands. That may sound familiar because that's where NASA's InSight lander set up shop several years ago to study the planet's internal structure. And wouldn't you know it, the probe's analysis of "marsquakes" shows that almost all of them originate around a series of fissures in Elysium Planitia known as Cerberus Fossae.
[...] When applying a tectonic model to the data, the team found a mantle plume was the only plausible explanation. Measurements show the plume measures about 2,500 miles across, which would be large even for Earth. It all adds up to a planet that has more going on under the surface than anyone thought. Future studies will have to explore the origins of this apparent mantle plume in a region where no one expected to find one.
Mars May Have a Huge Plume of Hot Rocks Rising Towards its Surface
Mars may have an enormous underground plume of hot rocks slowly rising towards the surface:
A strange system of trenches on Mars may be hiding an enormous plume of hot rock rising from the planet's core. This could upend our ideas of Mars as a mostly geologically static world and explain why so many marsquakes start near these fissures, which are known as Cerberus Fossae.
[...] Adrien Broquet and Jeffrey Andrews-Hanna at the University of Arizona hypothesised that this could all be explained by a phenomenon called a mantle plume, in which hot material from near the planet's core begins to rise through the mantle of the planet, causing shaking and volcanic activity as it goes. "If you were to touch a mantle rock at its mantle temperature and pressure, it would definitively feel solid. But on a million years timescale, it will flow," says Broquet.
If there is a mantle plume, it ought to press up on the ground atop it, creating a large hill and fracturing the ground. Cerberus Fossae has exactly those characteristics, and computer models of how the area would evolve over time with a mantle plume pressing upwards were an exact match. The models suggested that the plume measures more than 3500 kilometres across and is up to 285 degrees hotter than the surrounding area.
[...] The heat from a plume would also melt some of the material above it, creating magma that may eventually seep out onto the surface. In fact, the seismic activity detected by InSight is probably related to magma rising through the ground, Broquet says.
That warmth could also be a boon for the potential of life on Mars. "The plume may also provide the heat to melt water underground, and I don't want to be too optimistic, but on Earth this is an environment where microbes flourish," says Broquet.
Journal Reference:
Broquet, A., Andrews-Hanna, J.C. Geophysical evidence for an active mantle plume underneath Elysium Planitia on Mars. Nat Astron (2022). https://doi.org/10.1038/s41550-022-01836-3 (DOI: 10.1038/s41550-022-01836-3)
(Score: 2) by kazzie on Friday December 09 2022, @12:37PM
With various social media companies making the news these days, and one of them named in the previous article, I managed to misread the title as:
Meta is Still Geologically Active
Perhaps rumours of their death have been exaggerated?
(Score: 2) by bzipitidoo on Friday December 09 2022, @06:16PM (1 child)
Can a terrestrial planet be geologically active and yet not have a liquid core with accompanying geomagnetic field?
(Score: 0) by Anonymous Coward on Friday December 09 2022, @09:55PM
Yes.