‘Mars isn’t dead’: Recent Volcanic Activity on Red Planet

Most volcanic activity that has occurred on Mars happened billions of years ago, but recent evidence of volcanic activity could have taken place in the last 50,000 years.

The new study by the University of Arizona’s Lunar and Planetary Laboratory and the Planetary Science Institute has located what they believe is the “youngest volcanic deposit yet documented on Mars”. This is according to lead study author David Horvath, a research scientist at the Planetary Science Institute.

The eruption that happened many years ago, left a 13km wide, smooth, dark deposit that surrounds a 32km long fissure along the surface of Mars. It was spotted using data from satellites orbiting Mars. All of these findings are documented in ”Evidence for geologically recent explosive volcanism in Elysium Planitia, Mars”.

Further investigation showed that the properties, composition and how the material was spread out matches what would be expected for a pyroclastic eruption. These are cannon-like explosions of magma caused by expanding gas from the centre of the volcano.

“The deposit was unlike anything else found in the region, or indeed on all of Mars, and more closely resembled features created by older volcanic eruptions on the Moon and Mercury.” Said co-author and associate professor at UArizona Lunar and Planetary Laboratory, Jeff Andrews-Hanna.

The site of the eruption is about 1,609km away from NASA’s InSight lander, which has been monitoring seismic activity on Mars since 2018. Two Martian earthquakes, or Marsquakes, have been found to originate in the region of Cerberus Fossae, which recent work also suggests these were caused by the movement of underground magma.

Below the Surface of Mars

Horvath said that a volcanic deposit like this also increases the chance that conditions below the surface of Mars could have been inhabitable recently. “The interaction of ascending magma and the icy substrate of this region could have provided favourable conditions for microbial life fairly recently and raises the possibility of extant life in this region,” Horvath said.

Horvath also said “This feature overlies the surrounding lava flows and appears to be a relatively fresh and thin deposit of ash and rock, representing a different style of eruption than previously identified pyroclastic features”.

Pranabendu Moitra, a research scientist in the UArizona Department of Geo-sciences has been investigating what triggered the eruption. Moitra developed models to determine the cause and suggested that the explosion could have come from gases in the magma, or the magma interacting with Martian permafrost.

“The ice melts to water, mixes with the magma and vaporizes, forcing a violent explosion of the mixture,” Moitra said. He also notes this eruption happened almost 10km from the most recent large-crater impact on Mars, a 10km wide crater called Zunil.

The ages of both the eruption deposit and impact crater are indistinguishable which also raises the chances “that the impact actually triggered the volcanic eruption” as Moitra said.

Studies have shown earthquakes can cause magma under the crust to erupt and as such the impact that resulted in the Zunil crater could have caused Mars to shake similar to a quake said Moitra.

The volcanic activity in the Elysium Planitia region are generally lava flows, similar to eruptions in Iceland being studied by co-author and UArizona associate professor of lunar and planetary sciences Christopher Hamilton.

It is also notable that the Elysium region has seen modern day quakes, the most recent lava flows and water floods, and the most recent volcanic activity. This along with seismic rumbles in Mars’ interior detected by InSight and possible evidence showing methane plumes releasing into the atmosphere as detected by NASA’s MAVEN orbiter suggests Mars has not gone dark.

Andrews-Hanna said, “All these data seem to be telling the same story,”, that “Mars isn’t dead.”.