NASA has found evidence that roughly 4 billion years ago, an area on Mars called Arabia Terra experienced thousands of powerful and explosive volcanic eruptions that may have affected the Martian climate. This confirms previous theories that Mars was once a different place than what it looks like now.
NASA wrote that the super-eruptions are the biggest volcanic eruptions ever known and that they were "so powerful they release oceans of dust and toxic gases into the air, blocking out sunlight and changing a planet's climate for decades."
They described their findings in the study, titled "Stratigraphic Evidence for Early Martian Explosive Volcanism in Arabia Terra," which was published in the journal Geophysical Research Letters.
Massive, Ancient Volcanic Eruptions Happened on Mars in a Span of 500 Million Years
NASA said that the massive, ancient volcanic eruptions happened on Arabia Terra in a span of about 500 million years, a time when Mars was once a very different place from what it is today.
Scientists first noticed seven calderas or giant holes created at volcanic eruption sites at the site. It was previously known to be depressions caused by asteroid impacts. But a 2013 paper proposed another theory of origin for the calderas.
The paper suggests that the depressions were left behind after super-eruptions, wherein a supervolcano has blown its stack, released magma, and the rock above collapses in a sort of sinkhole.
Lead author Patrick Whelley, a geologist at NASA's Goddard Space Flight Center, said that they have read the paper and became interested in making a follow-up study. According to Fox News, Whelley and his team looked for ash as evidence for the super-eruptions that occurred billions of years ago.
In collaboration with volcanologist Alexandra Matiella Noval from Johns Hopkins Physics Laboratory, the team continued the work of the previous paper and examined surface minerals in Arabia Terra. They also used images from the Compact Reconnaissance Imaging Spectrometer of the Mars Reconnaissance Orbiter to study canyons and craters from hundreds of thousands of miles away from the calderas.
A 3D topographic map of the site showed that minerals turned to clay were layered and were exactly where scientists have estimated where they would have fallen billions of years ago. The team estimated that over half a dozen of supervolcanoes might have erupted every couple million years.
Super Eruptions Might Have Affected Martian Climate
Whelley said that each of the super-eruptions that happened billions of years ago might have caused a significant impact on the Martian climate. According to Science Alert, they hypothesize that the supervolcanoes must have released a gas that made the atmosphere of Mars thicker or that could have blocked the Sun, making the planet colder.
Super-eruptions are considered to be the most powerful volcanic eruptions that can release volcanic materials of more than 240 cubic miles (1,000 cubic kilometers) into the atmosphere and its surrounding terrain. But what baffles scientists now is how Arabia Terra could have only one kind of volcano.
NASA said that super-eruptions could also happen on Earth with the last one happening in Sumatra, Indonesia about 76,000 years ago. But today these volcanoes are dispersed around the globe and located in areas with different types of volcanoes.
Check out more news and information on Mars in Science Times.