Study: a Martian crater lake fed by glacial run-off
From figure 1 on the research paper.
A new study of a 33-mile-wide Martian crater in its southern cratered highlands has found evidence that a lake had once existed on the crater floor, and was fed entirely by glacial run-off in a cold climate, coming from its interior walls, not from outside the crater.
In a study published in Planetary Science Journal, a research team led by Brown Ph.D. student Ben Boatwright describes an as-yet unnamed crater with some puzzling characteristics. The crater’s floor has unmistakable geologic evidence of ancient stream beds and ponds, yet there’s no evidence of inlet channels where water could have entered the crater from outside, and no evidence of groundwater activity where it could have bubbled up from below.
So where did the water come from?
The researchers conclude that the system was likely fed by runoff from a long-lost Martian glacier. Water flowed into the crater atop the glacier, which meant it didn’t leave behind a valley as it would have had it flowed directly on the ground. The water eventually emptied into the low-lying crater floor, where it left its geological mark on the bare Martian soil.
You can read the full paper here. The crater is considered very old, which means this evidence dates from a very early Mars when the climate was very different. As the scientists note in their conclusion:
We find that the features within the crater are unlikely to have formed in a warm and wet early Mars climate dominated by fluvial valley network incision and crater breaching. … [Instead, w]e find that the ensemble of features within the crater (e.g., lack of wall-breaching fluvial channels, the presence of alcoves and upslope-facing scarps, and the nature and location of inverted fluvial channels and lacustrine deposits on the crater floor) are all consistent with the top-down melting of a cold-based crater wall glacier, proglacial drainage in fluvial meltwater channels, and ponding of meltwater in lakes on the crater floor.
The “inverted fluvial channels” (the ridges in the figure above) are believed to be ancient flow channels that became hardened and more resistant to erosion. As time passed the channel floor became a ridge as the surrounding terrain was eroded away. “Lacustrine deposits” are deposits created in lake environments.
Subsequently the researchers have found [pdf] forty more ancient craters in the same equatorial region with the same glacial features.
This research provides more evidence that glacial processes in a cold climate were possibly the fundamental cause of most of the geological features we see on Mars, not flowing water in a warm climate.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
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4. Donate by check, payable to Robert Zimmerman and mailed to
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From figure 1 on the research paper.
A new study of a 33-mile-wide Martian crater in its southern cratered highlands has found evidence that a lake had once existed on the crater floor, and was fed entirely by glacial run-off in a cold climate, coming from its interior walls, not from outside the crater.
In a study published in Planetary Science Journal, a research team led by Brown Ph.D. student Ben Boatwright describes an as-yet unnamed crater with some puzzling characteristics. The crater’s floor has unmistakable geologic evidence of ancient stream beds and ponds, yet there’s no evidence of inlet channels where water could have entered the crater from outside, and no evidence of groundwater activity where it could have bubbled up from below.
So where did the water come from?
The researchers conclude that the system was likely fed by runoff from a long-lost Martian glacier. Water flowed into the crater atop the glacier, which meant it didn’t leave behind a valley as it would have had it flowed directly on the ground. The water eventually emptied into the low-lying crater floor, where it left its geological mark on the bare Martian soil.
You can read the full paper here. The crater is considered very old, which means this evidence dates from a very early Mars when the climate was very different. As the scientists note in their conclusion:
We find that the features within the crater are unlikely to have formed in a warm and wet early Mars climate dominated by fluvial valley network incision and crater breaching. … [Instead, w]e find that the ensemble of features within the crater (e.g., lack of wall-breaching fluvial channels, the presence of alcoves and upslope-facing scarps, and the nature and location of inverted fluvial channels and lacustrine deposits on the crater floor) are all consistent with the top-down melting of a cold-based crater wall glacier, proglacial drainage in fluvial meltwater channels, and ponding of meltwater in lakes on the crater floor.
The “inverted fluvial channels” (the ridges in the figure above) are believed to be ancient flow channels that became hardened and more resistant to erosion. As time passed the channel floor became a ridge as the surrounding terrain was eroded away. “Lacustrine deposits” are deposits created in lake environments.
Subsequently the researchers have found [pdf] forty more ancient craters in the same equatorial region with the same glacial features.
This research provides more evidence that glacial processes in a cold climate were possibly the fundamental cause of most of the geological features we see on Mars, not flowing water in a warm climate.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
So with all the evidence of water on Mars I guess we will not see the same sort of sharp regolith as we do on the moon? Perhaps the water will have had some amount of erosion and perhaps current water could reduce the static charge.
Perseverance is to collect some samples if I remember. Will they closely photograph them to show if they have been worn by “Martian style erosion”?
Is it still true that the exoplanetary climate modelers cannot accommodate the increasingly possible “fact” that liquid water existed on the Martian surface?