The geology of the field at the equator of Mars indicates an ancient megaflood

Floods of unimaginable size once swept through Gale Crater on Mars’ equator some 4 billion years ago, a finding that suggests the possibility that life may have existed there, according to data collected by NASA’s Curiosity rover and analyzed in a project. joint by scientists from Jackson State University, Cornell University, Jet Propulsion Laboratory, and University of Hawaii.

The research, “Deposits from Giant Floods in Gale Crater and Their Implications for the Climate of Early Mars”, was published on November 5 in Scientific reports.

The furious mega-flood, likely caused by the heat of a meteor impact, which released the ice stored on the Martian surface, created giant ripples that are telltale geological structures familiar to scientists on Earth.

“We identified megafloods for the first time using detailed sedimentological data observed by the Curiosity rover,” said co-author Alberto G. Fairén, a visiting astrobiologist at the College of Arts and Sciences. “The deposits left by the megafloods had not previously been identified with the data from the orbiter.”

As with Earth, geological features, including the work of water and wind, have been frozen in time on Mars for about 4 billion years. These features convey processes that have shaped the surface of both planets in the past.

This case includes the presence of gigantic wave-shaped features in the sedimentary layers of the Gale crater, often called “megaripples” or antidunes that are about 30 feet tall and spaced about 450 feet apart, according to the lead author. Ezat Heydari, a physics professor at Jackson State University.

Antidunes are indicative of megafloods flowing at the bottom of Mars’ Gale crater about 4 billion years ago, which are identical to features formed by the melting of ice on Earth about 2 million years ago, Heydari said.

The most likely cause of the flooding of Mars was the melting of the ice due to the heat generated by a large impact, which released carbon dioxide and methane from the planet’s frozen reservoirs. Water vapor and the release of gases combined to produce a short period of warm, humid conditions on the red planet.

The condensation formed clouds of water vapor, which in turn created torrential rains, perhaps all over the planet. That water entered the Gale Crater, then combined with the water flowing down from Mount Sharp (in the Gale Crater) to produce gigantic flash floods that deposited the gravel ridges in the Hummocky Plains drive and the ridge band formations and depressions in the Striated Unit.

The science team of the Curiosity rover has already established that Gale Crater once had persistent lakes and streams in the ancient past. These long-lived bodies of water are good indicators that the crater, as well as Mount Sharp within it, were capable of supporting microbial life.

“Early Mars was an extremely active planet from a geologic point of view,” Fairén said. “The planet had the necessary conditions to support the presence of liquid water on the surface and on Earth, where there is water, there is life.

“So at the beginning of Mars it was a habitable planet,” he said. “Was it inhabited? That’s a question the next Perseverance rover … will help answer.”

Perseverance, launched from Cape Canaveral on July 30, will reach Mars on February 18, 2021.