Mars does not have active plate tectonics like Earth, so apart from some volcanic activity in the first 1.5 billion years of its birth, it is often regarded as a peaceful dead star with little internal activity. However, scientists recently discovered a mushroom-shaped, hot, floating mantle pillar under the Elysium Planitia (Elysium Planitia), indicating that Mars is not yet quiet, and the seemingly calm surface may hide a more turbulent interior than imagined.
Mantle plume is a way of thermal convection in the planet’s mantle. The hot rock rises from the bottom of the mantle to the top of the mantle. At this time, the top of the rock is partially melted and magma is ejected from the surface. It may be a hot spot or flood basalt. It is known that the Earth and Venus have active mantle heat column activities.
As for the cold and dry planet of Mars, although volcanic activity in the first 1.5 billion years created the tallest volcano in the solar system, Olympus Mons, and volcanic deposits cover most of the northern hemisphere, it is now generally regarded as Death Star, so scientists do not expect Mars to have mantle pillars.
However, the University of Arizona team was drawn to an inconspicuous region of Mars called Elysium Planitia, which has experienced massive eruptions over the past 200 million years, has an unusually strong local gravity field, and is still alive only about 53,000 years ago. Years of volcanic sediment evidence, mantle columns could explain all of the above anomalies.
The researchers analyzed Mars satellite data and developed models. As a result, plumes at least 3,500 kilometers in diameter were found 1,500 kilometers below the Cerberus Fossae crack in the plain. These rock pillars caused the surface to rise, coupled with subtle changes in the gravity field. The team It is pointed out that this uplift is consistent with the characteristics of the mantle heat column.
We used to think that InSight landed in the most boring area of Mars geological activity, but new research shows that InSight just landed on the top of the active plume, and the seismic data it recorded may help scientists better understand the geological evolution of Mars in the future, and Mars will also become the third solar system planet with mantle thermal column activity after the Earth and Venus.
The new paper was published in the journal Nature Astronomy.
(First image source: ESA)
