A lava flow on a Martian lava plain
Click for original image.
While much of surface of the Martian equatorial regions is comprised of volcanic flood lava, the place where it is most obvious and evident is on the flanks of the three giant volcanoes of the Tharsis Bulge. Here, lava did not simple spout from surface vents to flood low-lying large areas, filling those depressions quickly almost like water. Instead it issued from vents on the slopes of those mountains, or from their calderas at their peaks, and flowed downhill almost like tsunamis of magma.
The picture to the right, rotated, cropped, reduced, and sharpened to post here, is a great example. Taken on March 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows the foot of one such flow, frozen in place as it oozed down hill from the Arsia Mons, about 300 miles away to the northwest.
The green dot west of Claritas Fossae on the overview map to the right marks this location. Such downhill flows to the southeast are not unusual in this region. In fact, they are very common, showing that the volcanic events that caused them and built up Arsia Mons were many over time, with each placing another layer on top. Only when researchers can drill deep core samples at these locations to record those many layers will we finally be able to record the long volcanic history of Mars, and begin to understand the planet’s full geological history.
One intriguing aspect of this picture is only visible at full resolution. Take a look. For some reason the surface of this flood lava is covered with a fine stippling of tiny ridges, almost of which are oriented in a north-south direction. Are these dunes shaped by the prevailing winds? Erosion features in the lava? Your guess is as good as mine.
Readers!
Every February I run a fund-raising drive during my birthday month. This year I celebrate my 72nd birthday, and hope and plan to continue writing and posting on Behind the Black for as long as I am able.
I hope my readers will support this effort. As I did in my November fund-raising drive, I am offering autographed copies of my books for large donations. Donate $250 and you can have a choice of the hardback of either Genesis: the Story of Apollo 8 or Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space. Donate $200 and you can get an autographed paperback copy of either.
Please consider supporting my work here at Behind the Black. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID 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. Every one of those 2020 conclusions has turned out right.
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.
Click for original image.
While much of surface of the Martian equatorial regions is comprised of volcanic flood lava, the place where it is most obvious and evident is on the flanks of the three giant volcanoes of the Tharsis Bulge. Here, lava did not simple spout from surface vents to flood low-lying large areas, filling those depressions quickly almost like water. Instead it issued from vents on the slopes of those mountains, or from their calderas at their peaks, and flowed downhill almost like tsunamis of magma.
The picture to the right, rotated, cropped, reduced, and sharpened to post here, is a great example. Taken on March 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows the foot of one such flow, frozen in place as it oozed down hill from the Arsia Mons, about 300 miles away to the northwest.
The green dot west of Claritas Fossae on the overview map to the right marks this location. Such downhill flows to the southeast are not unusual in this region. In fact, they are very common, showing that the volcanic events that caused them and built up Arsia Mons were many over time, with each placing another layer on top. Only when researchers can drill deep core samples at these locations to record those many layers will we finally be able to record the long volcanic history of Mars, and begin to understand the planet’s full geological history.
One intriguing aspect of this picture is only visible at full resolution. Take a look. For some reason the surface of this flood lava is covered with a fine stippling of tiny ridges, almost of which are oriented in a north-south direction. Are these dunes shaped by the prevailing winds? Erosion features in the lava? Your guess is as good as mine.
Readers!
Every February I run a fund-raising drive during my birthday month. This year I celebrate my 72nd birthday, and hope and plan to continue writing and posting on Behind the Black for as long as I am able.
I hope my readers will support this effort. As I did in my November fund-raising drive, I am offering autographed copies of my books for large donations. Donate $250 and you can have a choice of the hardback of either Genesis: the Story of Apollo 8 or Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space. Donate $200 and you can get an autographed paperback copy of either.
Please consider supporting my work here at Behind the Black. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID 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. Every one of those 2020 conclusions has turned out right.
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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