Water on Mars absorbed like a sponge, new research suggests

Mars: Not as dry as it seems
Image shows modern Mars (left) dry and barren, compared with the same scene over 3.5 billion years ago covered in water (right). The rocks of the surface were slowly reacting with the water, sequestering it into the Martian mantle leading to the dry, inhospitable scene shown on the left. Credit: Jon Wade

When searching for life, scientists first look for an element key to sustaining it: fresh water.

Although today's Martian surface is barren, frozen and inhabitable, a trail of evidence points to a once warmer, wetter planet, where water flowed freely. The conundrum of what happened to this water is long standing and unsolved. However, new research published in Nature suggests that this water is now locked in the Martian rocks.

Scientists at Oxford's Department of Earth Sciences, propose that the Martian surface reacted with the water and then absorbed it, increasing the rocks oxidation in the process, making the planet uninhabitable.

Previous research has suggested that the majority of the water was lost to space as a result of the collapse of the planet's magnetic field, when it was either swept away by high intensity solar winds or locked up as sub-surface ice. However, these theories do not explain where all of the water has gone.

Convinced that the planet's minerology held the answer to this puzzling question, a team led by Dr Jon Wade, NERC Research Fellow in Oxford's Department of Earth Sciences, applied modelling methods used to understand the composition of Earth rocks to calculate how much water could be removed from the Martian surface through reactions with rock. The team assessed the role that rock temperature, sub-surface pressure and general Martian make-up, have on the planetary surfaces.

The results revealed that the basalt rocks on Mars can hold approximately 25 per cent more water than those on Earth, and as a result drew the water from the Martian surface into its interior.

Dr Wade said: "People have thought about this question for a long time, but never tested the theory of the water being absorbed as a result of simple rock reactions. There are pockets of evidence that together, leads us to believe that a different reaction is needed to oxidise the Martian mantle. For instance, Martian meteorites are chemically reduced compared to the surface rocks, and compositionally look very different. One reason for this, and why Mars lost all of its water, could be in its minerology.

"The Earth's current system of plate tectonics prevents drastic changes in surface water levels, with wet rocks efficiently dehydrating before they enter the Earth's relatively dry mantle. But neither early Earth nor Mars had this system of recycling water. On Mars, (water reacting with the freshly erupted lavas' that form its basaltic crust, resulted in a sponge-like effect. The planet's water then reacted with the rocks to form a variety of water bearing minerals. This water-rock reaction changed the rock mineralogy and caused the planetary surface to dry and become inhospitable to life."

As to the question of why Earth has never experienced these changes, he said: "Mars is much smaller than Earth, with a different temperature profile and higher iron content of its silicate mantle. These are only subtle distinctions but they cause significant effects that, over time, add up. They made the surface of Mars more prone to reaction with surface water and able to form minerals that contain water. Because of these factors the planet's geological chemistry naturally drags water down into the mantle, whereas on early Earth hydrated rocks tended to float until they dehydrate."

The overarching message of Dr Wade's paper, that planetary composition sets the tone for future habitability, is echoed in new research also published in Nature, examining the Earth's salt levels. Co-written by Professor Chris Ballentine of Oxford's Department of Earth Sciences, the research reveals that for life to form and be sustainable, the Earth's halogen levels (Chlorine, Bromine and Iodine) have to be just right. Too much or too little could cause sterilisation. Previous studies have suggested that halogen level estimates in meteorites were too high. Compared to samples of the meteorites that formed the Earth, the ratio of salt to Earth is just too high.

Many theories have been put forward to explain the mystery of how this variation occurred, however, the two studies combined elevate the evidence and support a case for further investigation. Dr Wade said "Broadly speaking the inner planets in the solar system have similar composition, but subtle differences can cause dramatic differences - for example, rock chemistry. The biggest difference being, that Mars has more iron in its mantle rocks, as the planet formed under marginally more oxidising conditions."

We know that Mars once had water, and the potential to sustain life, but by comparison little is known about the other planets, and the team are keen to change that.

Dr Wade, said: "To build on this work we want to test the effects of other sensitivities across the planets - very little is known about Venus for example. Questions like: what if the Earth had more or less iron in the mantle, how would that change the environment? What if the Earth was bigger or smaller? These answers will help us to understand how much of a role chemistry determines a planet's future fate.

When looking for life on other planets it is not just about having the right bulk chemistry, but also very subtle things like the way the planet is put together, which may have big effects on whether stays on the . These effects and their implications for other have not really been explored."

Explore further

Extensive water in Mars' interior

More information: The divergent fates of primitive hydrospheric water on Earth and Mars, Nature by Jon Wade, Brendan Dyck, Richard M. Palin, James D. P. Moore & Andrew J. Smye, DOI: 10.1038/nature25031
Halogens in chondritic meteorites and terrestrial accretion, by Patricia L. Clay, Ray Burgess, Henner Busemann, Lorraine RuziƩ-Hamilton, Bastian Joachim, James M. D. Day & Christopher J. Ballentine, Nature, DOI: 10.1038/nature24625
Journal information: Nature

Citation: Water on Mars absorbed like a sponge, new research suggests (2017, December 20) retrieved 23 September 2019 from https://phys.org/news/2017-12-mars-absorbed-sponge.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Dec 20, 2017
No, and there was no great flood.

Dec 20, 2017
There is no water on Mars. It evaporated long ago and disappeared, thanks to low gravity.

Dec 21, 2017
there is proof of past water levels being higher and erosion marks all over the globe. something caused that.

There have been changes in ice levels in the arctic/antarctic over geological timespans. This has lead to sea levels being rather drastically different over time (and one reason why we should not take the current, rapid climate change lightly...because while we can possibly counter droughts with better irrigation measures there's just no way we can combat higher sea levels which lead to destruction of arable land by contamination of the groundwater with saltwater and us having to abandon all coastal cities - which are basically all major cities in the world)

not to mention extinct civilizations and creatures that have been fossilized

Fossilization has nothing to do with sea levels.

Dec 21, 2017
And the planets are some sort of "living beings", they breathe, which means they spread and gather in time. Mars is now in the expansion stage and therefore there is no water or atmosphere on it. Why reduces the magnetic field of the planet? If the water and the atmosphere are absorbed into the planet's envelope, then the magnetism changes, and especially since the other planets and suns influence the magnetic field of each planet. The earth is in the shrinking phase, and Venus has reached maximum compression from the inside The various gases produced by compaction of the place where the lava has its position is ejected from the planets.

Dec 21, 2017
Oh, milnik, milnik, milnik. And, uhhmm, A7.

Really? I mean, even for you guys, your comments have achieved a new low of bat-shit crazy!

You guys gotta stop chewing on those peyote buds. That crap ain't doing your pitiful intellects any favors.

Damn! As pestiferously incohebriated as you two have been? I actually feel sorry for you.

Dec 21, 2017
From your high "cultural expressions" and your level of awareness, it is no surprise that you have no idea about yourself, not to mention the structure of the universe. Just keep on evaluating what you have no idea, and you will, after all, after a couple of hundred incarnations get a little bit of awareness that will introduce you to the knowledge of strangers.

Dec 21, 2017
antialias... I have to take issue with your statement that coastal cities include all the major cities of the world. Moscow, Toronto, Chicago, Mexico City, Berlin, Paris, Cairo, Beijing, Atlanta are just a few that are not on the coast or major waterways that would be affected by likely sea level rise. Plenty will be, of course, and that is a big problem.

Dec 21, 2017
antialias... I have to take issue with your statement that coastal cities include all the major cities of the world. Moscow, Toronto, Chicago, Mexico City, Berlin, Paris, Cairo, Beijing, Atlanta are just a few that are not on the coast or major waterways that would be affected by likely sea level rise. Plenty will be, of course, and that is a big problem.

Well, Chicago and Toronto are next to large bodies of water....

Dec 21, 2017
how do you know if your thought reality is real?

How do you know if your thoughts are really Putin's?

Dec 22, 2017
Moscow, Toronto, Chicago, Mexico City, Berlin, Paris, Cairo, Beijing, Atlanta are just a few that are not on the coast

Even relocating just one city would cost a multiple of what it would take to mitigate climate change. Can you imagine what relocating something like Miami would cost? Alexandria? Shanghai? Osaka? Rio de Janeiro?

In my mind I see the world as Gotham.

Contradiction in terms. You have no mind. What you post is BS. Utter.

Dec 22, 2017
Water Cycle on Dry as a Bone Mars.
Water bound in Perchlorate crystals is the answer to all the questions.
1. What rain falls on Mars?
2. What lakes fill up with on Mars?
3. What do you fill your two buckets with on Mars?
4. What gives 1 bucket of water when boiled at 24C on Mars?
5. What yields water dew twice a day on Mars?
6. Why build a habitat next to a lake on Mars?
7. What makes up 1% of the regolith on Mars?
8. Where did the oceans go for conservation when Mars dried up?
9. Where does the ice ablation of the poles go in summer on Mars?
10. What flows across the surface of Mars faster than sand?
Tony Lance Dip.Math(Open) 22nd November 2017

Dec 22, 2017
Okay TL, we're back to speculating about a Mars colony accessing water bound into perchlorate crystals.

How much energy does it take to release water from PC? And what will be your power source?

What percentage of water is contained in a a kiloton of the PC? Is the PC available to scoop up from the surface? Or, will you have to dig it up? How much tonnage of material will have to be moved and sorted out, to recover a ton of unprocessed PC ore?

What is your plan? Your funding & logistical organization.
1. Moving all the machinery and humans?/robots? to Mars.
2. Locating assayed ore bodies close enough to your colony to keep the costs to a reasonable level.
3. Would it simplify matters, locating your colony near a workable PC site?

The above is just a fraction of what would need to be done, first! Wouldn't herding cometary ice be cheaper?

As a start, all the above info you will need to begin planning, can be found accessing comparative Earth mining operations.

Dec 25, 2017
It is really interesting to unravel the differences in terrestrial planets. The article model came to my attention right after a local one claiming Mars Express shows Mars' magnetic field history may not explain as much of the atmosphere loss as historically thought:

"Despite the absence of a global Earth-like magnetic dipole, the Martian atmosphere is well protected from the effects of the solar wind on ion escape from the planet. New research shows this using measurements from the Swedish particle instrument ASPERA-3 on the Mars Express spacecraft."

[ https://www2.irf....stration ]

If there was no escape induced greenhouse collapse, models of crust uptake seems promoted.

Returning to astrobiology, serpentinization is suggested to be a global mechanism behind emergence of life. The more active such of Mars and likely ice moons such as Enceladus is suggestive for where life may develop and survive.

Dec 25, 2017
science is not fact. depends upon the honesty of the scientist. science could be fact.

It is a fact that science is useful despite scientists being no less and no more prone to cheating than other professions, see economical statistics on both claims. It is also trivial fact that settled science is majority opinion among experts and that such opinion is well supported by the facts that settled the area in question.

This is a science site and your incredulity, opinion and absence of both fact references and understanding of what science is is irrelevant to the rest of us. If you ask relevant questions in order to understand science, the rest of us will likely try to respond in kind. If not, you will stand out as someone to simply ignore.

Also, the religious Gish gallop of incessant, inflammatory posed questions, is trivially stupid. Continue at your own risk to seem even less relevant in science discussions.

Dec 26, 2017
t_b_g_l, from my reading of the present research. If there was life on Mars? That was billions of years ago. Even deep-aresology extremophiles are unlikely without tectonic activity from the Mars core.

As for the outer moons such as Enceladus? My opinion, no evidence, that the 'oceans' will turn out to a sterile mush of water and other liquefied gasses. A very small chance that lifeforms evolved for that environment. Will we even recognize those as life? And avoid poisoning them with physical contact?

I suspect our only chance to discover living organisms will be on Titan. Possibly similar to the Pre-Oxygenization microlife of Earth.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more