Snowball Mars?

Guest “have rock hammer, will travel” by David Middleton

Early Mars was covered in ice sheets, not flowing rivers

SCIENCE, HEALTH & TECHNOLOGY

Aug 3, 2020    |   For more information, contact Sachintha Wickramasinghe

A large number of the valley networks scarring Mars’s surface were carved by water melting beneath glacial ice, not by free-flowing rivers as previously thought, according to new UBC research published today in Nature Geoscience. The findings effectively throw cold water on the dominant “warm and wet ancient Mars” hypothesis, which postulates that rivers, rainfall and oceans once existed on the red planet.

To reach this conclusion, lead author Anna Grau Galofre, former PhD student in the department of earth, ocean and atmospheric sciences, developed and used new techniques to examine thousands of Martian valleys. She and her co-authors also compared the Martian valleys to the subglacial channels in the Canadian Arctic Archipelago and uncovered striking similarities.

“For the last 40 years, since Mars’s valleys were first discovered, the assumption was that rivers once flowed on Mars, eroding and originating all of these valleys,” says Grau Galofre. “But there are hundreds of valleys on Mars, and they look very different from each other. If you look at Earth from a satellite you see a lot of valleys: some of them made by rivers, some made by glaciers, some made by other processes, and each type has a distinctive shape. Mars is similar, in that valleys look very different from each other, suggesting that many processes were at play to carve them.”

The similarity between many Martian valleys and the subglacial channels on Devon Island in the Canadian Arctic motivated the authors to conduct their comparative study. “Devon Island is one of the best analogues we have for Mars here on Earth—it is a cold, dry, polar desert, and the glaciation is largely cold-based,” says co-author Gordon Osinski, professor in Western University’s department of earth sciences and Institute for Earth and Space Exploration.

[…]

Grau Galofre’s theory also helps explain how the valleys would have formed 3.8 billion years ago on a planet that is further away from the sun than Earth, during a time when the sun was less intense. “Climate modelling predicts that Mars’ ancient climate was much cooler during the time of valley network formation,” says Grau Galofre, currently a SESE Exploration Post-doctoral Fellow at Arizona State University. “We tried to put everything together and bring up a hypothesis that hadn’t really been considered: that channels and valleys networks can form under ice sheets, as part of the drainage system that forms naturally under an ice sheet when there’s water accumulated at the base.”

These environments would also support better survival conditions for possible ancient life on Mars. A sheet of ice would lend more protection and stability of underlying water, as well as providing shelter from solar radiation in the absence of a magnetic field—something Mars once had, but which disappeared billions of years ago.

[…]

The University of British Columbia

The article features this collage of Mars’ Maumee valleys (top) and Devon Island (bottom):

Collage showing Mars’s Maumee valleys (top half) superimposed with channels on Devon Island in Nunavut (bottom half). The shape of the channels, as well as the overall network, appears almost identical. Credit: Cal-Tech CTX mosaic and MAXAR/Esri.

Interesting hypothesis… It actually may explain Mars’ sedimentary geology better than the current generally accepted hypothesis of a warm-wet Mars 3.0 to 3.8 billion years ago. Sounds like an awesome field trip!

Unfortunately, the paper is pay-walled.

Reference

Grau Galofre, A., Jellinek, A.M. & Osinski, G.R. Valley formation on early Mars by subglacial and fluvial erosion. Nat. Geosci. (2020). https://doi.org/10.1038/s41561-020-0618-x

43 thoughts on “Snowball Mars?

  1. serious question…I know…for a change

    The ice didn’t just show up as ice….it had to have come from water at some point, right?

    • Water is very common in the universe, consisting of the most abundant element by far and the third most in the solar system.

      Whether the molecule arrives on a planet in gaseous, liquid or solid form doesn’t really matter much.

  2. It has never made much sense that Mars had vast quantities of liquid oceans etc, since when this was meant to have happened, around 3.5 to 4.2 billion years ago, it was during the time of the faint sun.

    Given the distance from the sun and given that the sun is thought to have been some 30% to 40% less bright, there simply would not have been enough energy for liquid water to exist in vast quantities, at any rate not outside the equatorial region of the planet.

    • “….at any rate not outside the equatorial region of the planet.”

      We don’t know equatorial region of Mars, billions of years ago. Ie:
      “Mars and Earth share a similar angle of axial tilt – Mars at its present 25 degrees, and Earth at a fairly constant 23.5 degrees. During the past ten million years, Earth’s axial tilt has only varied between about 22 and 24.5 degrees, because our relatively large Moon helps maintain a stable tilt. But Mars, which has two tiny moons, has experienced more extreme changes in its axial tilt – between 13 and 40 degrees over timescales of about 10 to 20 million years.”
      http://phoenix.lpl.arizona.edu/mars102.php

      It seems to me Mars would have more “geothermal” energy 3 billion years ago.
      As would Earth have more “geothermal” energy 3 billion years ago.
      But since Mars is smaller there would have greater difference with Mars as compared to Earth.

  3. Hi David, good to see your post again.
    “have rock hammer, will travel”
    Have one one of those (Estwing). Well travelled, from Scottish highlands, Elba, Santorini, Kimberly, South Atlantic deep sea dredger, all the way up to snow ball Northwest Territories’ Gahcho Kue, inherited from my youngest. Every man should have an Estwing.

    • Yours is far more well-traveled than mine… Which hasn’t hit an actual rock in years… 😉

        • I recently used mine, with a chisel, to clean mortar off tiles I was repairing… Only broke one of the ones that was already broken… 😎

          • David
            Does your business card say “Palliton?” 🙂

            Incidentally, while I own several Estwing hammers, and prefer the long-handled model for breaking rocks, I think that the Plumb (no longer manufactured) with a fiberglass handle was a superior design.

          • My blogging business card does…

            However, Debunkhouse has become more of a scratch pad and file cabinet than a blog…😎

    • I still have my 1st Estwing–with the leather wrapped handle. Purchased as an undergrad for field methods course. Lots of others over the course of a 50 year mineral exploration career. Hammer of choice for work in the PC Shield was a 3# crack hammer…those old rocks are tough. My grand son thinks rock hammers are “cool” .

  4. Looks like good work.

    Who’s going to man the rotary rig site to do some real drilling, sampling, bagging, and field microscope work?

  5. Rather than a Snowball Mars, the authors propose ice sheets covering the southern highlands.

    Presumably ice didn’t covered the northern lowlands, where others have supposed liquid water ocean. The presumed subglacial valleys are in the southern highlands.

    • “Snowball Mars?” was just a short, catchy thread title. It wasn’t meant to be a summary of the article. When possible, I prefer to have short thread titles.

    • Forrest Baker,
      The Heinlein book, “Have Spacesuit, Will Travel,” was published in August of 1958; over a year earlier the iconic TV western “Have Gun, Will Travel” was first aired. The number of plays on the wording are quite extensive now; when I was playing cowboy and Western music in a previous lifetime I used a copy of Paladin’s card (including the black knight chess piece) with Gun crossed off and Guitar written over it.

      Sadly, I have not been able to locate my old Estwing rock hammer. I think it’s somewhere in my box of hammers along with several Estwing framing hammers and other relics of the Construction Era. And yes, if you must know, AOC is dumber than that box!

      • “The Heinlein book, “Have Spacesuit, Will Travel,” was published in August of 1958”

        That was the second science fiction book I ever read, probably in about 1958. The first one I read was named “The Wonderful Planet” but I don’t recall the author. That fired my imagination and caused my interest in space development. I read every science fiction book in the library and when they ran out, I read every science fact book about space development they had. I wanted so bad to be a member of the British Interplanetary Society. I actually joined that organization when I got older and had a little money.

        I noticed after a while that the the science fiction and science fact book sections were being updated with new books almost on a weekly basis and it dawned on me some time later that the librarians knew my interests and were feeding me books on a regular basis (I did ask them frequently if they had any new books). I spent a lot of time in the library when I was a kid and got to know the librarians pretty well. God Bless those wonderful women for taking care of me.

    • Solid water (ice) contains pockets of liquid water, and gaseous water evaporates from liquid and sublimes from solid. Same-same.

  6. Yup, I like this hypothesis…It makes common sense given the distance from the Sun and a lower internal heat source (lower mass means the initial internal heat can radiate out much faster and there is less heat produced from radioactive materials). I have often wondered how Mars could have had great volumes of liquid water and yet been so cold. And if Mars wasn’t cold the the Earth must have been really hot at that time.

    They should be able to find terminal moraines if glaciers were active, possibly buried under sand and dust now but they should be there.

  7. David,
    Thanks for another fascinating article! Wouldn’t it be great to be part of the first team of geologists doing the field work! Does this point to water being a much more common component of our Universe than previously theorized?

  8. David, Do they mention eskers? These are a major feature in this type of melting environment on Earth.

    • Unfortunately, the paper is pay-walled. I think they mostly focused on the drainage patterns. But, if these features are due to sub-glacial fluvial activity, I wouldn’t be surprised if esker and kame-type features are discovered. After seeing this article, I started to think maybe the deltaic appearing feature in Jezero crater might be a kame delta.

      Perseverance will be exploring Jezero crater… So,we may get some answers in the next few years.

  9. Martian canals don’t make much sense then. Who would think about transporting ice through canals? 😉

  10. I still have my 1st Estwing–with the leather wrapped handle. Purchased as an undergrad for field methods course. Lots of others over the course of a 50 year mineral exploration career. Hammer of choice for work in the PC Shield was a 3# crack hammer…those old rocks are tough. My grand son thinks rock hammers are “cool” .

  11. Interesting how the same tool can have different names in different industries.
    Being a brick/block/stone mason all my working life, I’ve always known what you call a 3 lb. “crack hammer” as a “mash hammer”.
    And what most people here call a “rock hammer” (one end shaped like a chisel, the other having a square hammer head) I’ve always known as a “brick hammer”. To me, a rock hammer had “pick heads” on both ends.

    After my dad (also a bricklayer) retired, he had an old leather wrapped Estwing brick hammer that he carried around on his little tractor for cutting, digging, hitting, etc. while he was doing things on the “back 40”. I still have that hammer.

    • I have two rubber-handled Estwing rock hammers, one with a chisel end (Mason’s or bricklayer’s hammer) and the other a pick end (rock pick). And a small sledge (drilling hammer).

      https://www.estwing.com/collections/geological

      Unfortunately, for me, the only tools for home repairs that I am proficient with, are duck (duct) tape and bungee cords… 😉

    • The pick end hammers are for igneous and metamorphic rocks (hard rocks). The brick hammer type are for sedimentary rocks (soft rocks). When you specialize in one type of rock, you are obligated to disparage the others. Not quite Hatfields and McCoys, though when departmental budgets come along it can get there.

      Myself, I was bi-rock type, and found a Stanley brick hammer was the best, split sediments like a soft rock hammer but was a bit heavier and broke up Precambrian crystalline rocks quite well. My thesis hammer was eventually left in a van on some AAPG field trip after drinking too much free Schlumberger beer.

  12. From the above excerpts of the Science, Health & Technology article:
    ” ‘. . . and the glaciation is largely cold-based,’ says co-author Gordon Osinski . . .”

    Just wondering if there is any other possible basis for forming (ice) glaciers other than low temperatures? That would be ≤ 0 C for water ice and ≤ -56 C for carbon dioxide ice.

    Perhaps Kurt Vonnegut’s ice-nine is alive and well on Mars?

  13. Interesting article. I wondered about oceans on Mars and wonder if enhanced imagery may have been able to detect any salt deposits?

    What is the difference between sea ice and icebergs, glaciers, and lake ice?

    The most basic difference is that sea ice forms from salty ocean water, whereas icebergs, glaciers, and lake ice form from fresh water or snow. Sea ice grows, forms, and melts strictly in the ocean. Glaciers are considered land ice, and icebergs are chunks of ice that break off of glaciers and fall into the ocean. Lake ice is made from fresh water and freezes as a smooth layer, unlike sea ice, which develops into various forms and shapes because of the constant turbulence of ocean water.

    The process by which sea ice forms is also different from that of lake or river ice. Fresh water is unlike most substances because it becomes less dense as it nears the freezing point. This difference in density explains why ice cubes float in a glass of water. Very cold, low-density fresh water stays at the surface of lakes and rivers, forming an ice layer on the top.

    In contrast to fresh water, the salt in ocean water causes the density of the water to increase as it nears the freezing point, and very cold ocean water tends to sink. As a result, sea ice forms slowly, compared to freshwater ice, because salt water sinks away from the cold surface before it cools enough to freeze. Furthermore, other factors cause the formation of sea ice to be a slow process. The freezing temperature of salt water is lower than fresh water; ocean temperatures must reach -1.8 degrees Celsius (28.8 degrees Fahrenheit) to freeze. Because oceans are so deep, it takes longer to reach the freezing point, and generally, the top 100 to 150 meters (300 to 450 feet) of water must be cooled to the freezing temperature for ice to form.

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