Thousands Of Volcanic Super Eruptions Rocked Ancient Mars
A new NASA study has confirmed that over a period of 500 million years, Mars witnessed thousands of massive volcanic eruptions that spewed enough ash and gases to block the planet’s surface from sunlight and helped shape the Red Planet’s current topography. The presence of volcanoes on Mars has been known for years. In fact, Mars is home to the largest volcano in the solar system called Olympus Mons, which has a height of roughly 21.9 km and is nearly two and a half times taller than Mount Everest. So far though, it has been believed that there are no active volcanoes on the Martian surface.
But in May this year, a study from scientists at the University of Arizona's Lunar and Planetary Laboratory and the Planetary Science Institute proposed that Mars might still be volcanically active. Based on evidence collected by satellites orbiting the planet, the team noted that volcanic eruptions happened as recently as 50,000 years ago. Based on the study, it was argued that warmth from these volcanic eruptions could have provided conditions that are habitable for life and will offer more intriguing details about the planet’s history.
A study funded by NASA, which has been published in the journal Geophysical Research Letters, has now provided more ‘explosive’ details about the Martian surface from billions of years ago, hinting that certain regions of the planet were once quite an infernal spectacle. Analysis of the mineral composition and movement pattern of ash confirmed that depressions spotted in the Arabia Terra region of Northern Mars were not depressions caused by an asteroid impact, but they were actually caldera. A caldera forms after the magma chamber empties following a volcanic eruption, leaving a massive cauldron-like depression that appears when the ground surface collapses downward. It’s not the discovery of the volcanoes that is amazing, but rather the sheer scale of how massive these volcanic eruptions were, and something that future Mars missions will definitely explore in-depth.
Based on the available surface data and comparative modeling, scientists estimate that the Arabian Terra witnessed anywhere between 1,000 to 2,000 ‘super eruptions’ in a span of roughly 500 million years. These gigantic volcanic eruptions happened with an average repose interval of 1.8-3.5 million years during the late Noachian and early Hesperian era, leaving volcanic ash deposits as thick as one kilometer near the caldera and thinning up to 100 meters away from the eruption site.
To give an idea of how terrifying such explosions were on Mars, a ‘super eruption’ sits at magnitude 8 on the Volcano Explosivity Index (VEI), the highest figure on the list, and has a measured volume of deposits exceeding 1,000 cubic kilometers. The amount of gas and ash from such as eruption is enough to block sunlight for a long-time, leading to a drastic fall in temperature. The latest NASA study is just another piece of the puzzle about Mars and has left scientists wondering how a planet as small as Mars could internally generate enough heat and form magma to cause thousands of such eruptions in one region.
Source: NASA