Thousands of massive ancient volcanoes erupted on Mars, according to NASA scientists. They’ve found the evidences which proves it.
The so-called “super eruptions” occurred in Arabia Terra, a region of northern Mars, over a 500-million-year period, roughly 4 billion years ago.
The discovery was made by researchers studying the topography and mineral composition of the region, and the news was published in the journal Geophysical Research Letters in July 2021.
“Each one of these eruptions would have had a significant climate impact — maybe the released gas made the atmosphere thicker or blocked the sun and made the atmosphere colder,” Patrick Whelley, a geologist at NASA’s Goddard Space Flight Center who led the Arabia Terra analysis, said in a release. “Modelers of the Martian climate will have some work to do to try to understand the impact of the volcanoes.”
The “first giveaways” were seven calderas, which are large holes created by volcanic eruptions.
The calderas were initially thought to be asteroid impact depressions, but scientists discovered in 2013 that they were showing signs of collapse and weren’t perfectly round.
“We read that paper and were interested in following up, but instead of looking for volcanoes themselves, we looked for the ash because you can’t hide that evidence,” Whelley said.
The team examined surface minerals and picked up on previous work that had calculated where ash from possible super eruptions would have fallen, working with volcanologist Alexandra Matiella Novak of the Johns Hopkins Applied Physics Laboratory.
They studied the walls of canyons and craters from hundreds to thousands of miles away from the calderas, using images from the Mars Reconnaissance Orbiter’s Compact Reconnaissance Imaging Spectrometer to identify volcanic minerals turned into clay by water.
They created three-dimensional topographic maps of Arabia Terra and compared mineral data to the maps to see if the ash layers had been preserved.
The number of eruptions will be determined by NASA using calculations of how much material would have exploded from the volcanoes based on the volume of each caldera.
The puzzle of how a planet could have only one type of volcano in one area remains unsolved.
“It’s possible that super-eruptive volcanoes were concentrated in regions on Earth but have been eroded physically and chemically or moved around the globe as continents shifted due to plate tectonics,” the NASA release states. “These types of explosive volcanoes also could exist in regions of Jupiter’s moon or could have been clustered on Venus.”
