Terrain geology at Mars equator indicates ancient mega-flooding

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

The research, “Giant Flood Deposits in Gale Crater and their Implications for Early March Climate,” was published on November 5 in Scientific reports.

The raging mega-flood – likely triggered by heat from a meteorite impact, which released stored ice on the Martian surface – created gigantic ripples that are telltale geological structures familiar to scientists on Earth.

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

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

This case includes the appearance of giant wave-shaped features in the sedimentary layers of Gale Crater, often referred to as “mega-pearls” or antidunes about 9 meters high and spaced about 450 meters apart, according to lead author Ezat Heydari. , physics teacher. at Jackson State University.

Antidunes point to mega-floods that sank to the bottom of Mars’ Gale crater about 4 billion years ago, which are identical to the features formed by the melting ice on Earth about 2 million years ago, Heydari said.

The most likely cause of the flooding on Mars was the melting ice caused by heat generated by a large impact, which released carbon dioxide and methane from the planet’s frozen reservoirs. The water vapor and the evolution of gas combined to produce a short period of hot and humid conditions on the Red Planet.

The condensation formed clouds of water vapor, which in turn created torrential, eventually planetary rains. This water entered Gale Crater and then combined with the water coming down from Mount Sharp (in Gale Crater) to produce gigantic flash floods that deposited the gravel ridges in the Hummocky Plains unit and ridges and valleys band formations in the striated unit.

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

“The start of Mars was an extremely geologically active planet,” 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 early on, Mars was a habitable planet,” he says. “Was it manned? That’s a question the next Perseverance rover … will help answer.”

Perseverance, which launched from Cape Canaveral on July 30, is expected to reach March on February 18, 2021.