Ancient flood lava in the Martian cratered highlands
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 4, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The ridges were the primary reason this photo was taken, as they cover a 50-mile-square region of relatively flat terrain that also appears to be a series of steps downward to the west. The dotted line on the picture indicates one of those steps downward, with the plain to the west of that line about 100 to 200 feet lower that the plain to the east.
My first guess was that these ridges might be inverted channels, but that really didn’t make sense considering their random nature completely divorced from the downward grade. Then I took a wider view, and came up with a better guess.
The white dot on the overview map to the right marks the location, in Arabia Terra, the largest transistion zone between the northern lowland plains and the southern cratered highlands of Mars. Arabia however has more in common with the cratered highlands, as it is cratered in much the same way, suggesting it is very ancient terrain left over from the heavy bombardment during the formation of the planets, four billion years ago.
That ancient terrain however has been significantly reshaped since that heavy bombardment, most often by volcanic activity. It appears that the dotted line actually denotes the edge of one flood of ancient lava, of which there appear to be several. The oldest is to the west. As you go east and north and climb those steps, you are traversing up onto later floods, one by one. The different floods show up as plains of different brightnesses, with the most recent the brightest.
But what formed the ridges? I suspect these ridges are wrinkle ridges, formed when that lava solidified and shrank. That shrinkage formed cracks, similar to what you see in dried mud, that were later filled with more resistent material. When later erosion stripped away the top of the lava, the ridges remained.
This is still a mere guess. What is more certain is the volcanic nature of these plains. Much of this part of Arabia Terra was formed from volcanic events in the far past, lava spewing out of vents to flood large areas, but forming no volcanoes of note.
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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, reduced, and sharpened to post here, was taken on February 4, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The ridges were the primary reason this photo was taken, as they cover a 50-mile-square region of relatively flat terrain that also appears to be a series of steps downward to the west. The dotted line on the picture indicates one of those steps downward, with the plain to the west of that line about 100 to 200 feet lower that the plain to the east.
My first guess was that these ridges might be inverted channels, but that really didn’t make sense considering their random nature completely divorced from the downward grade. Then I took a wider view, and came up with a better guess.
The white dot on the overview map to the right marks the location, in Arabia Terra, the largest transistion zone between the northern lowland plains and the southern cratered highlands of Mars. Arabia however has more in common with the cratered highlands, as it is cratered in much the same way, suggesting it is very ancient terrain left over from the heavy bombardment during the formation of the planets, four billion years ago.
That ancient terrain however has been significantly reshaped since that heavy bombardment, most often by volcanic activity. It appears that the dotted line actually denotes the edge of one flood of ancient lava, of which there appear to be several. The oldest is to the west. As you go east and north and climb those steps, you are traversing up onto later floods, one by one. The different floods show up as plains of different brightnesses, with the most recent the brightest.
But what formed the ridges? I suspect these ridges are wrinkle ridges, formed when that lava solidified and shrank. That shrinkage formed cracks, similar to what you see in dried mud, that were later filled with more resistent material. When later erosion stripped away the top of the lava, the ridges remained.
This is still a mere guess. What is more certain is the volcanic nature of these plains. Much of this part of Arabia Terra was formed from volcanic events in the far past, lava spewing out of vents to flood large areas, but forming no volcanoes of note.
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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