Geology at the Martian equator suggests a massive flood in the distant past

Researchers have been looking at the field geology on the equator of Mars and found that it suggests an ancient flood of an unimaginable magnitude washed through Gale Crater on the Martian equator about 4 billion years ago. The finding suggests that there is a possibility life may have existed around Gale Crater billions of years ago.

The new finding comes thanks to data collected by the Curiosity rover that was analyzed in a joint project by scientists from Jackson State University, Cornell, University of Hawaii, and the Jet Propulsion Laboratory. Researchers believe that the megaflood was likely started from the heat of a meteorite impact that melted ice stored on the Martian surface. The researchers say that gigantic ripples on the surface near the equator indicate a flood, and similar structures are found on Earth.

The researchers were able to identify megafloods for the first time using detailed sedimentological data observed by the curiosity rover. Deposits left behind from massive flooding hadn't been previously identified using orbiter data. Researchers note that geological features, including the effects of water and wind, have been frozen in time on Mars for about 4 billion years.

The geological markers indicate processes that shaped the surface of Mars in the past. Mars has giant wave-shaped features in the sedimentary layers of Gale Crater, referred to as "megaripples" or antidunes. The features are about 30-feet high and spaced about 450 feet apart. They are indicative of flowing water in the bottom of Gale crater about 4 billion years ago. The structures are identical to features formed by melting ice on Earth about 2 million years ago.

The most likely cause of flooding on Mars was melting ice from heat generated by large impact releasing 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 and wet conditions on Mars. Condensation formed by water vapor clouds created torrential rain, possibly planetwide. The water entered Gale Crater combined with water coming down Mount Sharp to produce massive flash floods that deposited gravel ridges below.