New evidence of deep groundwater on Mars

New evidence of deep groundwater on Mars
Recurrent Slope Linae on the Palikir Crater walls on Mars. Credit: NASA/JPL/University of Arizona

In mid-2018, researchers supported by the Italian Space Agency detected the presence of a deep-water lake on Mars under its south polar ice caps. Now, researchers at the USC Arid Climate and Water Research Center (AWARE) have published a study that suggests deep groundwater could still be active on Mars and could originate surface streams in some near-equatorial areas on Mars.

The researchers at USC have determined that likely exists in a broader geographical area than just the poles of Mars and that there is an active system, as deep as 750 meters, from which groundwater comes to the surface through cracks in the specific craters they analyzed.

Heggy, who is a member of the Mars Express Sounding radar experiment MARSIS probing Mars subsurface, and co-author Abotalib Z. Abotalib, a postdoctoral research associate at USC, studied the characteristics of Mars Recurrent Slope Linea, which are akin to dried, short streams of water that appear on some crater walls on Mars.

Scientists previously thought these features were affiliated with surface water flow or close subsurface water flow, says Heggy.

"We suggest that this may not be true. We propose an alternative hypothesis that they originate from a deep pressurized groundwater source which comes to the surface moving upward along ground cracks," Heggy says.

"The experience we gained from our research in desert hydrology was the cornerstone in reaching this conclusion. We have seen the same mechanisms in the North African Sahara and in the Arabian Peninsula, and it helped us explore the same mechanism on Mars," said Abotalib Z. Abotalib, the paper's first author.

The two scientists concluded that fractures within some of Mars' craters, enabled water springs to rise up to the surface as a result of pressure deep below. These springs leaked onto the surface, generating the sharp and distinct linear features found on the walls of these craters. The scientists also provide an explanation on how these water features fluctuate with seasonality on Mars.

The study, to be published on March 28, 2019, in Nature Geoscience, suggests that groundwater might be deeper than previously thought in areas where such streams are observed on Mars. The findings suggest that the exposed part of these ground fractures associated with these springs as the primary location candidates to explore Mars' habitability. Their work suggests that new probing methods should be developed to study these fractures.


Previous research to explore groundwater on Mars relied on interpreting the returned electromagnetic echoes sent from the radar-probing experiments from orbit onboard Mars Express and Mars Reconnaissance Orbiter. These experiments measured the reflection of the waves from both the surface and the subsurface whenever penetration was possible. However, this earlier method did not yet provide evidence of groundwater occurrence beyond the 2018 South Pole detection.

The authors of this current Nature Geoscience study used hi-resolution optical images and modeling to study the walls of large impact craters on Mars. The goal was to correlate the presence of fractures with the sources of streams that generate short water flows.

Heggy and Abotalib, who have long studied subsurface aquifers and groundwater flow movement on Earth and in desert environments, found similarities between the groundwater moving mechanisms in the Sahara and on Mars.

"Groundwater is strong evidence for the past similarity between Mars and Earth—it suggest they have a similar evolution, to some extent," says Heggy.

He says this deep source of groundwater is the most convincing evidence of similarities between the two planets—it suggest both may have had wet periods long enough to create such an active groundwater system.

For Heggy, an advocate for water science and water science education in arid areas, this particular study is not about colonization. But he says these rare and puzzling water flows on Mars are of big interest to the science community.

"Understanding how groundwater has formed on Mars, where it is today and how it is moving helps us constrain ambiguities on the evolution of climatic conditions on Mars for the last three billion years and how these conditions formed this groundwater system. It helps us to understand the similarities to our own planet and if we are going through the same climate evolution and the same path that Mars is going. Understanding Mars' evolution is crucial for understanding our own Earth's long-term evolution and groundwater is a key element in this process. "

The new study suggests that the groundwater that is the source of these water flows could be at depths starting at 750 meters deep. "Such depth requires us to consider more deep-probing techniques to look for the source of this groundwater versus looking for shallow sources of water, " says Heggy.

Explore further

First evidence of planet-wide groundwater system on Mars

More information: A deep groundwater origin for recurring slope linea on Mars, Nature Geoscience (2019). ,
Journal information: Nature Geoscience

Citation: New evidence of deep groundwater on Mars (2019, March 28) retrieved 16 September 2019 from
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Mar 28, 2019
From the article
"the source of these water flows could be at depths starting at 750 meters deep."

-This is bad news for those who see mars as offering a unique opportunity to reestablish isolation between human settlements and artificial ecologies...

"there may be 100 million to 1 billion bacteria per gram of dry soil. These values decrease dramatically with soil depth below the root zone, with densities depending on the amount of nutrients (food) and water available. Although concentrations of microbes below the root zone are lower than in the root zone itself, as many as 10 to 100 million bacteria per gram of aquifer material may be present. Bacteria have been found in core samples from a depth of 2.8 kilometers (1.7 miles) below the Earth's surface, and at a depth of 3.2 kilometers in South African gold mines."

-It also means that, once we are there, planetwide contamination is most likely inevitable, unless of course mars biota finds earthlife palatable.

Mar 28, 2019
The two scientists concluded that fractures within some of Mars' craters, enabled water springs to rise up to the surface as a result of pressure deep below.

As Dr. Zubrin pointed out some time ago, an extant hot springs would make a Mars Base a whole lot easier. More important than a source of water and energy, and a source material for rocket fuel and life science studies, the first Mars base could have a large heated hot tube for the parties! :-)

Mar 29, 2019
But where are your 900 foot tall reclining glassy headed Martians that you're always talking about and saying that you've seen on Mars while attributing their discovery to someone else?
When you say, "once WE are there", does that mean that you are planning to fly to Mars on the next flight out? Have a good trip and don't come back.

Mar 29, 2019
So SEU/Pirouette/russkiye/obama_socks/RitchieGuy01/jewsrule/pussycat_eyes/pussytard is gonna be following me around now like a sick little puppy dog, as is always the case every time she pops up. You gonna be doing that with everyone here who cant stand your sickness pussytard? Per names for everyone?

You freak.

Sick little puppy dogs abound on the internet. You cant just let them shit and puke wherever they want.

Yay android can edit again. Thanks physorg.

Mar 30, 2019
This is consistent with that massive runoffs happened during a very prolonged period in Mars history, when it had little warmth and atmospheric pressure:

"Rivers raged on Mars late into its history
Scientists find substantial runoff fed rivers for more than a billion years

Date: March 27, 2019
University of Chicago
Scientists have catalogued these rivers to conclude that significant river runoff persisted on Mars later into its history than previously thought. According to the study, the runoff was intense -- rivers on Mars were wider than those on Earth today -- and occurred at hundreds of locations on the red planet."

[ https://www.scien...2018.htm ]

Mar 30, 2019
@TGO: "once we are there, planetwide contamination is most likely inevitable, unless of course mars biota finds earthlife palatable."

Yes, having groundwater will ease habitation and so contamination. so that is now likely. However, even if it will also increase the likelihood of extant life the two biota will be separable, they have been separated for a very long time or most likely have different genetic systems. It is unlikely anything else than autotrophs would evolve or persist in a resource poor underground environment and they aren't adapted for using us anyway so no threat, and it will be unlikely our own parasitic biota will make it there or by the same token be able to utilize it.

At least at first, I believe I read prokaryotes can push out - probably proteolytic - enzymes and pump them back with any added nutrients from dead - or alive - organisms. In any case, a later concern than having time to record the pristine biota.

Mar 30, 2019
Depends on where life comes from and how hungry it is I suppose. If life has a common origin, or arises according to very restrictive rules, then we might be food for mars life and vice versa. Then theres this

"Archaea share some characteristics with known pathogens that may reflect the potential to cause disease. Such characteristics include ample access to a host (i.e., opportunity) and capabilities for long-term colonization and coexistence with endogenous flora in a host. The detection of anaerobic archaea in the human colonic (36), vaginal (2), and oral microbial flora (1) demonstrates their ability to colonize the human host."

The quote from Jurassic park: "life will find a way."

Mar 31, 2019
Mars' atmosphere is half a percent that of Earth's. No exploration will ever be easy.

Apr 01, 2019
Mars' atmosphere is half a percent that of Earth's. No exploration will ever be easy.
In the arctic you can get frostbite in 2 minutes. "At the bottom of the marianas trench the water column above exerts a pressure of 1,086 bars (15,750 psi), more than 1,000 times the standard atmospheric pressure at sea level..."

-Both environments the exploration of which was considered unthinkable only a few gens ago. The dangers of exploration off-planet are grossly overblown. Progress in materials, energy production, medicine, and related tech will only make it easier in years to come.

Apr 01, 2019
I don't care how much water there maybe within the surface of Mars.
Will it be accessible where you need it? Right the hell now!
Will it be potable without excessively expensive cracking it out of toxic minerals?
Before sheer desperation drives you looney from you being forced to drink your own urine for the sixth straight week?

Oh & good luck getting rid of the native micro-orgamism after three bullion years of ruthless evolutionary pressure on a dying planet.

You going to

Apr 01, 2019
In case someone with industrial planning, processes or logistics should happen to accidentally stumble into these comments?

Ooh, a math quiz:
It takes how much delta_v to direct 100 tons of ice how many millions of Kms x how much delta_v to insert it into Mars orbit x how much delta_v to accelerate for a soft landing?
To produce one ton of steel in addition to all the other mining, transportation, storage, smelter construction, sub-processing of ingots[;us transpotation. storage, further processing into a multitude of steel products plus storage & transpoerting.

Adding that all up? Each steel girder will cost more than then making exact, life-size copies of Deimos & Phobos out of Solid Platinum & placing
the pair of sculptures on exhibit around Luna.

& I promise you, those not very exaggerated expenses (bye-bye taxes. up. up @ away!) of delivering potable water to Mars? Will be cheaper than trying to find & deliver usable Mars water!

Apr 02, 2019
mars was once wet.
mars was heavily bombarded, rubbleizing the crust to a depth of 40-60km.
mars did not experience tectonics. rubbleized crust was never subducted into the mantle.
as mars cooled and dried, water penetrated the shattered crust.
4 Gy later Mars is still wet but the wet exists in an extensive cave system formed by the rubbleization of the crust during the LHB.

Oh, and there be life there.

Apr 02, 2019
as far as I know? & i will admit limited experience with caves on Earth.

Where are cave systems located in Earth geography?
Rainy areas I believe.
With constant water cycling through.
Dissolving & carrying away much of the structural minerals.

Perhaps that was true for Mars during it;s first billion years?
Why would that ne true several billion years later?

But let us speculate that instead, for Mars specifically, that the water came up out of the lower depths?
Would that have created cavern systems as we think of them?
Would not the aquifer pressure continued to the surface, drawn by vacuum?
Where the water would have sublimated away into Space?

Leaving behind what nay have been caverns, filled with silt & calcite & other minerals dissolved ^ deposited by the traveling water?

Cause water, in whichever phase, does not stand still. The beat of the band & those hips start swiveling & the feet start to caper.
Water loovves to trip the light fantastic!

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