Ice, lava, quakes, and faults, all in one Martian image
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 25, 2021. It grabbed my attention because it possibly captures a whole range of Martian geological processes, all in one place, including evidence of quakes, of lava, of faults, and possibly of glaciers.
First, ignore the black rectangle, which is merely a small section of lost data.
The picture itself shows a wide north-south fissure, as indicated by the distinct western cliff and the fainter and less pronounced eastern cliff. This fissure, likely formed along a fault, was created when the crust was pushed and stretched upward by the pressure of underground volcanic magma, part of the long series of eruptions that formed the many similar and parallel north-south fissures south of the shield volcano Alba Mons.
The overview map below illustrates this fissure’s relationship with Alba Mons.
That upward stretching would have caused quakes as the ground was shifted, stretched, and cracked. Such cracks are called grabens by geologists, places where two pieces of surface crust become offset along a fault when one drops or the other rises.
Within this fissure however is material that suggests vaguely, but not certainly, the presence of buried glacial ice. The latitude is 33.5 degrees north, which places it far enough away from the equator for such glaciers to exist.
At the same time, the altitude is high, which tends to be dryer on Mars. The material filling the fissure could also be flood lava, coming downhill from Alba Mons to the north.
What strengthens the hypothesis that the material in the fissure is ice is the small secondary crack on its western edge. While this smaller canyon’s interior has many features suggestive of glaciers, it also appears that whatever flowed down this canyon ate into the material in the main canyon. If so, it is possible that the small canyon was a lava vent that when it reached the main canyon acted to heat and melt away the main glacier there.
All guesses, though taken all together the image suggests that both ice and lava contributed to this geology, after it was first formed by quakes and volcanic eruptions. A busy place indeed.
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Your support is even more essential to me because I not only keep this site free from advertisements, I do not use the corrupt social media companies like Google, Twitter, and Facebook to promote my work. I depend wholly on the direct support of my readers.
You can provide that support to Behind The Black with a contribution via Patreon or PayPal. To use Patreon, go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation. For PayPal click one of the following buttons:
If Patreon or Paypal don't work for you, you can support Behind The Black directly by sending your donation by check, payable to Robert Zimmerman, to
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c/o Robert Zimmerman
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Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 25, 2021. It grabbed my attention because it possibly captures a whole range of Martian geological processes, all in one place, including evidence of quakes, of lava, of faults, and possibly of glaciers.
First, ignore the black rectangle, which is merely a small section of lost data.
The picture itself shows a wide north-south fissure, as indicated by the distinct western cliff and the fainter and less pronounced eastern cliff. This fissure, likely formed along a fault, was created when the crust was pushed and stretched upward by the pressure of underground volcanic magma, part of the long series of eruptions that formed the many similar and parallel north-south fissures south of the shield volcano Alba Mons.
The overview map below illustrates this fissure’s relationship with Alba Mons.
That upward stretching would have caused quakes as the ground was shifted, stretched, and cracked. Such cracks are called grabens by geologists, places where two pieces of surface crust become offset along a fault when one drops or the other rises.
Within this fissure however is material that suggests vaguely, but not certainly, the presence of buried glacial ice. The latitude is 33.5 degrees north, which places it far enough away from the equator for such glaciers to exist.
At the same time, the altitude is high, which tends to be dryer on Mars. The material filling the fissure could also be flood lava, coming downhill from Alba Mons to the north.
What strengthens the hypothesis that the material in the fissure is ice is the small secondary crack on its western edge. While this smaller canyon’s interior has many features suggestive of glaciers, it also appears that whatever flowed down this canyon ate into the material in the main canyon. If so, it is possible that the small canyon was a lava vent that when it reached the main canyon acted to heat and melt away the main glacier there.
All guesses, though taken all together the image suggests that both ice and lava contributed to this geology, after it was first formed by quakes and volcanic eruptions. A busy place indeed.
I must unfortunately ask you for your financial support because I do not depend on ads and rely entirely on the generosity of readers to keep Behind the Black running. You can either make a one time donation for whatever amount you wish, or you sign up for a monthly subscription ranging from $2 to $15 through Paypal or $3 to $50 through Patreon.
Your support will allow me to continue covering science and culture as I have for the past twenty years, independent and free from any outside influence.
Your support is even more essential to me because I not only keep this site free from advertisements, I do not use the corrupt social media companies like Google, Twitter, and Facebook to promote my work. I depend wholly on the direct support of my readers.
You can provide that support to Behind The Black with a contribution via Patreon or PayPal. To use Patreon, go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation. For PayPal click one of the following buttons:
If Patreon or Paypal don't work for you, you can support Behind The Black directly by sending your donation by check, payable to Robert Zimmerman, to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
Or you can donate by using Zelle through your bank. You will need to give my name and email address (found at the bottom of the "About" page). The best part of this electronic option is that no fees will be deducted! What you donate will be what I receive.
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