Mars may erupt again
Research suggests that a Martian volcano twice as high as Everest was spewing lava much more recently than previously thought – and may do so again. Andrew Masterson reports.
Mars has long been
considered a geologically inert planet, silent and still since the massive
volcanic eruptions that fashioned much of its surface ended more than three
billion years ago.
However, new findings derived from images obtained by the Mars Orbiter Camera aboard the Mars Global Surveyor Mission have raised the intriguing possibility that lava may one day soon flow fresh across the Red Planet.
A team led by geology and geophysics graduate researcher David Susko, from the Louisiana State University, focused on a Martian volcano dubbed Elysium, the second highest on the planet and more than twice as high as Everest. The findings are published in Nature Scientific Reports.
Combining the satellite imagery with data acquired by the Mars Rover, Susko’s team determined that parts of Elysium’s lava deposits were only three to four million years old, three orders of magnitude younger than the lava laid down by Mar’s other volcanoes.
The data also revealed that Elysium’s more recent deposits were very low in thorium and potassium when compared to the levels present around other volcanoes and in non-volcanic sections of the planet’s crust. The paper terms the finding a “major depletion”.
The reasons for the big drop in these two radioactive elements remains unknown, but the team speculate that it may be evidence that Mar’s more recent eruptions have differed chemically from older ones.
If so, write the researchers, it’s a conclusion with “major implications for the history of Martian mantle evolution, such as how volcanic provinces were built up over time, and motivates future investigations into this province.”
Commenting on the observation that Elysium had erupted much more recently than the planet’s other volcanos, Susko says that in geologic terms, three million years is “like yesterday”.
"At least, we can't yet rule out active volcanoes on Mars," he adds. "Which is very exciting."