Newly Found Coastal Shelf on Mars Might be Finest Proof But for Lengthy-Gone Ocean | Jackson School of Geosciences

April 15, 2026

Scientists have found geological options on Mars that might level to the existence of a long-dried up ocean that when lined a 3rd of the Red Planet’s floor. The geological formation is a large and deep coastal shelf akin to the continental cabinets that jut beneath the water the place Earth’s land meets its oceans.

Their findings have been published in Nature on April 15.

As a key ingredient for all times, water on different our bodies within the photo voltaic system is a significant space of research. While it’s extensively accepted that Mars as soon as had some quantity of liquid water on its floor, it’s nonetheless unclear whether or not that water was restricted to lakes and streams, or if there was sufficient to kind long-lasting oceans.

This discovering of a coastal shelf is the perfect piece of proof to this point of an historical ocean on the Red Planet.

“It’s a strong additional piece of evidence supporting a northern ocean on Mars, but there’s plenty of follow-up work to be done for rovers to examine deposits and for further analysis of satellite data,” stated Abdallah Zaki, a postdoctoral researcher at The University of Texas at Austin Jackson School of Geosciences.

The research suggests new targets for future missions. If there as soon as was life on Mars, sedimentary deposits from the Martian coastlines may have preserved its signatures, simply as coastal sediments on Earth comprise a historic report of fossils from the continents.

The analysis was performed by Zaki and Caltech professor of geology Michael Lamb whereas Zaki was a postdoc at Caltech.

Past Mars missions have found geologic options that appear to be shorelines, however they’re delicate and are discovered at various elevations throughout the planet. If they have been true signatures of a steady ocean, these shorelines would want to all be on the identical elevation in the identical method that sea ranges are constant throughout Earth.

“If Mars did have an ocean, it dried up a long time ago — possibly several billion years ago, more than half of the age of the planet itself,” Lamb stated “There is hardly anything on Earth that is that old; anything on Mars from that time has been eroded by billions of years of wind blowing, volcanoes erupting, and other disturbances removing subtle features. We wanted to find a better topographic feature than shorelines that could be evidence for an ocean.”

Zaki and Lamb seemed first to Earth to find out which geological options are indicative of an ocean on our personal planet. Using pc simulations, they first “dried up” the oceans to see which topographic options remained.

The fashions confirmed that probably the most distinct function of the oceans is a flat band of land, as much as a number of a whole lot of kilometers large, wrapping the contours of the place land meets ocean like a hoop that continues to be round a drained bathtub. That band is named the continental shelf. Though sea ranges on Earth, and thus the situation of shorelines, have fluctuated over a few years, the continental shelf is a big landform that’s comparatively steady over time.

The group then checked out topographic knowledge of Mars taken by orbiters and located a similar band that means the presence of a protracted dried up ocean within the Martian northern hemisphere overlaying a 3rd of the planet’s floor. A landform like this takes time to kind — and notably is just not discovered round lakes — which signifies that the ocean should have existed stably for probably thousands and thousands of years.

Zaki stated that the query of Mars having a coastal shelf like Earth’s had merely not been requested earlier than.

“It’s very fundamental. If there is an ocean, there must be a shelf. This is a more stable topographic signature,” Zaki stated.

The paper is titled “Identifying the topographic signature of early Martian oceans.” Zaki and Lamb are the paper’s authors. Funding was supplied by Caltech, a Swiss National Science Foundation Postdoc Mobility Fellowship, and the Jackson School of Geosciences Distinguished Postdoctoral Fellowship on the University of Texas at Austin.

This story was tailored from a press launch by Caltech. You can discover the original coverage here.

This animation reveals the ocean degree of Mars’ historical ocean falling 500 meters. Credit: A. Zaki