Marsquakes, recent volcanism suggest Mars still has a mantle plume - Ars Technica

But perhaps its most striking finding has been that almost all of Mars' seismic activity appears to originate from a single location, a site called Elysium Planitia.

That area is also the site of the most recent volcanic activity we've detected on Mars.

But it also has signs of recent volcanic activity, though not nearly as much as the nearby Tharsis region, which contains Mars' largest volcanoes.

Instead, there are signs of large floods of volcanic material released from large fissures in Elysium Planitia.

There are also signs of pyroclastic flows that appear to be the product of the most recent volcanic activity on the red planet, dating from less than 200,000 years ago.

There are some potential explanations for these and other features of Elysium Planitia, but the researchers argue that a hot mantle plume is the only one that makes sense.

As mentioned above, Elysium Planitia has a series of fractures that are typically associated with compression, and these are thought to be a product of old terrain that's subsiding as the interior of Mars cools.

Finally, the volcanic material in the area has much higher levels of iron than other areas of Mars, a feature found in volcanism driven by mantle plumes on Earth.

The activity levels found in Elysium Planitia are much lower than hotspot-driven sites elsewhere on Mars, and they're at the low end of what you'd see at similar sites on Earth.

Earlier activity driven by mantle plumes should have removed some of the water from Mars' interior, making it more difficult for rocks to melt.

It was supposed to deploy an implement that measures the heat flow from Mars' interior to its surface, which should have shed light on any hot material nearby (the InSight landing site is right on top of the proposed mantle plume).