Layered mesa on Mars
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on June 24, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a distinctive mesa in a mountainous region in the cratered highlands of Mars, just north of Hellas Basin, the deepest basin on the red planet.
The mesa’s most distinctive feature are its terraced layers, a feature that MRO has found in numerous other places surrounding and inside Hellas Basin (see for example the cool images here, here, here, here, here, and here.)
On Earth the assumption would be that these terraced layers imply different sedimentary layers that erode at different rates, as best illustrated by the Grand Canyon in Arizona. On Mars that assumption is not unreasonable, but unlike Earth, those layers could not have been formed in connection with large ocean bodies creating seafloor layers from the deposit of sealife over centuries. Some other geological process over time formed them, with volcanism, either from volcanoes or impact, being the most likely.
The mesa’s location is indicated by the red cross on the overview map to the right. At 27 degrees south latitude, it is likely too close to the equator to show much glacial evidence, though this is not impossible. A close look at the full image however implies mostly dust, dunes, and bedrock, not glaciers.
Why there are so many exposed layered and terraced features in and surrounding Hellas probably speaks to its origin and later erosion. Hellas is believed the result of a single very large impact, suggesting the layered terrain within it is likely from impact melt. Layers on its perimeter, such as today’s image, could instead be layers deposited by either volcanic lava flows or eruptive ash deposits, only now being exposed during subsequent eons of erosion.
The color strip suggests that much of this terrain is coarse sand or bedrock, with a lot of dust and sand everywhere, especially at lower elevations.
While the full geological picture here remains unexplained, I find the mesa impressive, and remarkably reminiscent of the mesas scattered through the Grand Canyon. It just formed in a different way.
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.
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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 on June 24, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a distinctive mesa in a mountainous region in the cratered highlands of Mars, just north of Hellas Basin, the deepest basin on the red planet.
The mesa’s most distinctive feature are its terraced layers, a feature that MRO has found in numerous other places surrounding and inside Hellas Basin (see for example the cool images here, here, here, here, here, and here.)
On Earth the assumption would be that these terraced layers imply different sedimentary layers that erode at different rates, as best illustrated by the Grand Canyon in Arizona. On Mars that assumption is not unreasonable, but unlike Earth, those layers could not have been formed in connection with large ocean bodies creating seafloor layers from the deposit of sealife over centuries. Some other geological process over time formed them, with volcanism, either from volcanoes or impact, being the most likely.
The mesa’s location is indicated by the red cross on the overview map to the right. At 27 degrees south latitude, it is likely too close to the equator to show much glacial evidence, though this is not impossible. A close look at the full image however implies mostly dust, dunes, and bedrock, not glaciers.
Why there are so many exposed layered and terraced features in and surrounding Hellas probably speaks to its origin and later erosion. Hellas is believed the result of a single very large impact, suggesting the layered terrain within it is likely from impact melt. Layers on its perimeter, such as today’s image, could instead be layers deposited by either volcanic lava flows or eruptive ash deposits, only now being exposed during subsequent eons of erosion.
The color strip suggests that much of this terrain is coarse sand or bedrock, with a lot of dust and sand everywhere, especially at lower elevations.
While the full geological picture here remains unexplained, I find the mesa impressive, and remarkably reminiscent of the mesas scattered through the Grand Canyon. It just formed in a different way.
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.
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