Isolated flat-topped mesa inside large Martian crater
Click for original image.
Cool image time! The picture to the right, cropped and reduced to post here, was taken on February 18, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The camera team labels this “layers in butte”, but because we are looking straight down at this 400-foot-high butte, it is difficult to see any layers at all. Based on most Martian geology however it would be shocking if this butte is not made up of multiple horizontal layers, ending with that flat surface layer at the top. Moreover, the base of the mesa to the northeast is clearly made up of a series of terraces that appear obscured at other points due to the presence of dust and dunes.
A side view would help clarify the number of layers and their thickness, but it does appear that this butte contains evidence of the geology that once covered this whole area, but over eons has eroded everything away but this butte.
On the overview map to the right the small rectangle inside 250-mile-wide Cassini Crater marks the location. The inset shows that this mesa sits inside a depression that appears to widen to the west. Thus, the mesa’s top appears to give us a glimpse of the same surface seen on the plateaus to the north and south. Erosion has removed the material in-between to leave the mesa sitting alone inside this depression.
Elevation data however shows that the mesa top is actually higher than the plateaus to the north and south, suggesting this mesa was the high point of that plateau, before erosion left it isolated.
Why did the mesa not get worn away as well? My guess is that the top of the mesa is actually the floor of an ancient crater. The impact compressed the ground so that it was more resistent to erosion. When the surrounding terrain was worn away, the crater remained, and eventually became the isolated mesa we see now.
Readers!
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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:
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Click for original image.
Cool image time! The picture to the right, cropped and reduced to post here, was taken on February 18, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The camera team labels this “layers in butte”, but because we are looking straight down at this 400-foot-high butte, it is difficult to see any layers at all. Based on most Martian geology however it would be shocking if this butte is not made up of multiple horizontal layers, ending with that flat surface layer at the top. Moreover, the base of the mesa to the northeast is clearly made up of a series of terraces that appear obscured at other points due to the presence of dust and dunes.
A side view would help clarify the number of layers and their thickness, but it does appear that this butte contains evidence of the geology that once covered this whole area, but over eons has eroded everything away but this butte.
On the overview map to the right the small rectangle inside 250-mile-wide Cassini Crater marks the location. The inset shows that this mesa sits inside a depression that appears to widen to the west. Thus, the mesa’s top appears to give us a glimpse of the same surface seen on the plateaus to the north and south. Erosion has removed the material in-between to leave the mesa sitting alone inside this depression.
Elevation data however shows that the mesa top is actually higher than the plateaus to the north and south, suggesting this mesa was the high point of that plateau, before erosion left it isolated.
Why did the mesa not get worn away as well? My guess is that the top of the mesa is actually the floor of an ancient crater. The impact compressed the ground so that it was more resistent to erosion. When the surrounding terrain was worn away, the crater remained, and eventually became the isolated mesa we see now.
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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