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Ara Pacis
2012-Aug-20, 12:01 AM
UCLA Planetary Geologist An Yin thinks that Mars may have tectonic activity

I quoted an article about Yin's ideas (from early last year) a few days ago in another thread. However, I just say that UT and other sites posted news about him a couple days ago and I was wondering what anyone who has read his papers or knows about planetary geology thinks of his ideas.

from January 3, 2011 (http://www.space.com/9683-surface-mars-possibly-shaped-plate-tectonics.html)

A patch of land near the huge Martian volcano Olympus Mons may bear evidence of recent plate tectonic activity on the Red Planet, new research suggests.

The many ridges and scarps on the rumpled apron of land north and west of Olympus Mons are likely signs of tectonic thrusting, according to the study. And this activity could be very recent — within the last 250,000 years or so.

He identifies certain structures in various photos, and he goes on to say other items such as shifting drainage channels indicate movement, Valles Marineris is widely thought to be a tectonic feature, a line of volcanoes may indicate crustal motion over a hot spot and magnetic striping in some areas all indicate tectonic motion.

From August 17, 2012 (http://www.universetoday.com/96856/scientists-find-clues-of-plate-tectonics-on-mars/)

“When I studied the satellite images from Mars, many of the features looked very much like fault systems I have seen in the Himalayas and Tibet, and in California as well, including the geomorphology,” he said.

The two plates that Yin calls Valles Marineris North and Valles Marineris South are moving approximately 93 miles horizontally relative to each other. By comparison, California’s San Andreas Fault, which is similarly over the intersection of two plates, has moved about twice as much, because Earth is about twice the size of Mars.

Yin believes Mars has no more than two plates whereas Earth has seven major plates and dozens of smaller ones. As Yin puts it “Earth has a very broken ‘egg shell,’ so its surface has many plates; Mars’ is slightly broken and may be on the way to becoming very broken, except its pace is very slow due to its small size and, thus, less thermal energy to drive it. This may be the reason Mars has fewer plates than on Earth.”

Iv'e read that most suggest that Mars both has no magnetosphere and isn't tectonic because it's interior cooled, but isn't tectonics the major mechanism for moving heat out of the core? If so, then how does it cool off. Could it be via volcanoes alone? And how cool would the core be?

I'm wondering if it's a matter of temperature or a matter of circulation. Could the circulation have been fatally disrupted by the proposed impact that created the proposed Borealis Basin (http://en.wikipedia.org/wiki/North_Polar_Basin_(Mars)) and the Martian Dichotomy (http://en.wikipedia.org/wiki/Martian_dichotomy)? Or could an ancient slab (http://en.wikipedia.org/wiki/Slab_(geology)) have subducted down towards the core (as happens on earth) but due to the smaller size of the core and distance from the crust, could it have projected into or cooled one section of the liquid core (if it exists) and have stopped the a global circulation by stopping convection but without substantially cooling the entire core?

dgavin
2012-Aug-20, 10:37 AM
Ara,

Bearing in mind that at best I'm an amatuer volcanologist, I took my own look at the terraign here, http://www.google.com/mars/.

I have to say that in the case of the first link to his work, he is off base there. This type of formation is very common on earth, where you have an older lava/debris flow, overlayed by more recent ones. Additionally if you compare his elevation snapshot, to the raw one on google, you will notice that some things about it have been subtly alter with shading to make it appear techtonic like. At a minimum I find that just a bit, on the dishonest side. Using the Infrared mode on Google maps makes the older flow rather appearant.

As too Olympus Mons, and Valles Marineris, The nice things about Mars, is being able to pay attention to crater pockmarking in the south, versus the north. It gives you a good idea of actualy how resent the north had water, and that, it appears to have had water, been exposed the had water again multiple times. Additionaly the entire region of the Volcano's in Olympus Mons, is likewise, devoid of the pockmarking of the south, meaning it's a much more recent feature over all. If you look at the volcano's to the NW of there, you can see those are older ones, with a bit more cratering on them.

The entire area of Olympus Mons appears to have all the ear marks of a volcanic uplift area, with evident stress formations surounding it. Similar to how the origin of a fire can be determined, they all seem to point to the general area of uplift stresses, not techtonic ones.

While Valles Marineris does have many earmark that make it look like a spreding zone of two plates, there are a few things that don't flow with that thinking. It's too long and two strait for a ridge zone. There is the area where it once met the sea, that indicates this canyon was once a major inlet of water into that north sea, likely the water came from the volcano's, and it was likely the main path for replenishing the sea's with water.

So my over all assement is, that the reasearcher is being perhaps a little dishonest in the 'enchanced' images he's utilizing, and is likely stretching, to find eveicence of techtonics.

Ara Pacis
2012-Aug-20, 08:33 PM
When you say volcanic uplift, do you mean from a magma chamber beneath or from the shield volcano cone-building process? I'm tryingto picture in my head why either of those would cause Valles Marineris.

How would water come from the valcanos? Do you mean from precipitation runoff or do you mean from the planet's interior?

dgavin
2012-Aug-20, 11:07 PM
From the magma chamber beneath, though the shield building process itself wiped out most the the craters in that uplifted area.

The water from all appearences came from the volcanoes themself, likely because of the amount of frozen water thats suspected to be under the soil. From what I can see there was likely an older deeper ocean, that erodded most of the older craters, sometime after (millions of years) there was another episode of volcanism, that didn't fill the ocean as much, leading to the more recent second shoreline.

With each eruption some water came out and began carving the canyon, as the volanoes settled down, and the canyon dried out, the two volcanoes had reached a size that altered the winds on mars, compressing them between the volcanoes into the canyon region, at that point winds took over the errosion process. But if you look at the far end of Valles Marineris you can see the tell tale signs of it's original water based origin, in the form of an river/ocean estuary, now dried up.

If you look at the amount of newer craters in the north ocean basin, per a similar sized area of the uplift area, that it about matches the number of craters, meaning they are roughly the same age, geologicaly speaking.

Ara Pacis
2012-Aug-21, 06:25 AM
Do you mean volcanic venting of water, or ground-ice meltwater from the periphery of the volcanoes? So you think Valles Marineris is purely erosional?

dgavin
2012-Aug-21, 02:19 PM
Do you mean volcanic venting of water, or ground-ice meltwater from the periphery of the volcanoes?

I would think both were going on, but the bulk was from ground ice melting.

So you think Valles Marineris is purely erosional?

Yes, there are other less impressive canyons around that area, which are more river looking, because wind did not errode them as much later.

I think there were four processes going on, that made Valles Marineris what it is today.

It strated with faulting as the uplifting began, ray like faults going out from the uplift zone.

As the magma pushed to the surface, it began heating the water which percolated out of the uplift area, into that faulting zone (some of these 'rivers' may have been underground at first, with the overlaying ground collapsing as the ice was melting). This heated water, also caused localized ice melting in the canyon area as it flowed, which weakened the infrastructer, allowing the water to carve the area deeply, taking the overlaying soil with it. This also made some of the blind canyons that seem to be partly connected.

The water from the erupting volcanoes them selves added to the amount of water some, but most of that wen into the atmosphere, and came down later as snows. The bulk of the water though came from the heating of the uplift area.

As the volcanoes continued to erupt, the ash burried most of the evidence of the water flows nearer to the volcanoes.

After the volcanic cycles were done, the wind errosion took over, and continued to dig out the canyon over time, aided by the volcanoes focusing the winds between them.

Ara Pacis
2012-Aug-21, 10:21 PM
So, if there's no tectonics, then how did the core of Mars cool down and lose it's dynamo (if it had one)? Is the vulcanism enough or was it simple heat-flow, that is conduction to the surface and then radiation into the atmosphere/space? How hot might the interior still be?

dgavin
2012-Aug-22, 02:19 AM
So, if there's no tectonics, then how did the core of Mars cool down and lose it's dynamo (if it had one)?

It's my guess, that until we have geologist there, we won't find be able to asertain if there were more achient volcanoes that were eroded or not. So it;s an unknown until we get there, however the fractured magnatism on Mars does indicate it at one time had an active magnetic field, which implies a hotter, active core.

Is the vulcanism enough or was it simple heat-flow, that is conduction to the surface and then radiation into the atmosphere/space? How hot might the interior still be?

The loss of the core heat I think was via conduction and radiation.

As far as what triggered the recent vulcanism, I am attaching an image of mars, where I inverted the left half over the right half, drew circles around where the left featues were on the right side, then got rid of the inverted layer, and then drew the matching circles on the left half.

It's rather telling, in that it appears, that those more recent volcanoes we can still see, might all be related to impact activity on the other side of the planet from them. As to what order the events happened in, thats an unknow until we can get something there that can analyze them.

Ara Pacis
2012-Aug-23, 10:33 PM
So, if there's no tectonics, then how did the core of Mars cool down and lose it's dynamo (if it had one)?

It's my guess, that until we have geologist there, we won't find be able to asertain if there were more achient volcanoes that were eroded or not. So it;s an unknown until we get there, however the fractured magnatism on Mars does indicate it at one time had an active magnetic field, which implies a hotter, active core.All the more reason to send people in my opinion. :) Do you suppose that heating from radioactive decay was more or less similar or proportional to Earth?


Is the vulcanism enough or was it simple heat-flow, that is conduction to the surface and then radiation into the atmosphere/space? How hot might the interior still be?

The loss of the core heat I think was via conduction and radiation.

As far as what triggered the recent vulcanism, I am attaching an image of mars, where I inverted the left half over the right half, drew circles around where the left featues were on the right side, then got rid of the inverted layer, and then drew the matching circles on the left half.

It's rather telling, in that it appears, that those more recent volcanoes we can still see, might all be related to impact activity on the other side of the planet from them. As to what order the events happened in, thats an unknow until we can get something there that can analyze them.

Thanks for the image. I've read about the antipodal possibility, though I don't recall which crater is related to which volcano(s) and it's not clear which ones are paired-up in your image (I can look it up later). Would that require a still hot core and/or mantle that would move into a fracture zone or would the impact itself be expected to provide enough heating at the antipodal focus for the vulcanism.

The point of my query into the Martian interior is whether it has significant geothermal energy available to settlers in some or all areas and whether there's a possibility that whatever stopped the dynamo might someday revert on its own or through human interference.

Now, I'm wondering what might be the effect of water on planetary magnetic fields and how that varies with salts and metals in it, and the possible electrical thunderstorms the basins may have supported. It's probably nothing, but I don't know if I don't ask.

dgavin
2012-Aug-24, 12:59 AM
Look at the Circle colors on my map to match impacts area's to antipodal volcanoes.

Do you suppose that heating from radioactive decay was more or less similar or proportional to Earth?

I think Mars would of had a different decay rate, as earths core, is the product of a merger of two planets, that formed the earth/moon system as we have today. Earhts core was recharged by that event, it was also reheated some, just from the merging of the two cores.

Would that require a still hot core and/or mantle that would move into a fracture zone or would the impact itself be expected to provide enough heating at the antipodal focus for the vulcanism.


I would think that the mantel would still need to be somewhat plastic like, probably atleast 600c for the impacts to induce vulcanism from antipodal heating. I'm not certain how hot the core would be for a 600c minimum in the mantle .

The point of my query into the Martian interior is whether it has significant geothermal energy available to settlers in some or all areas

I would say yes to all of mars. Assuming the mantle was at 600c over all the planet before the impact events, that on average, it reheated to around 750c globally, with the volcanic region being reheated to around 1200-1500c.


whether there's a possibility that whatever stopped the dynamo 1. might someday revert on its own or 2. through human interference.

1. No, not without a large body merger event that added to the surface and core material. 2. Only if we develop technology to add huge amount of radioactive materials into the core, in a human timely manner.

Now, I'm wondering what might be the effect of water on planetary magnetic fields and how that varies with salts and metals in it

I can't answer this one I'm afraid. I'm more knowagle in volcanic and tectonic processes, then chemical ones.

the possible electrical thunderstorms the basins may have supported.

Dust can cause thunderstorms as well, much in the same way erupting vocanoes can. Mars spawns some entire planet covering dust storm at times. Nice images of dust lightning on Google here https://www.google.com/search?q=dust+storm+lightning&hl=en&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=m9E2UNDHHcjligLJiYFA&sqi=2&ved=0CEgQsAQ&biw=1423&bih=897

Selfsim
2012-Aug-24, 05:23 AM
There appears to have been some past controversy about the degree of net influence planetary magnetic fields may actually have, when accounting for present-day volumes of atmospheres (and water content). The controversy seems to have revolved around the mean escape rates of atmospheric oxygen, water, and neutral ions being similar amongst Venus, Earth and Mars, all being similar.

As a result, I am left with some questions about just how valid the magnetic shield hypothesis really is, as the sole explanation for the past planetary environments.

The impact of a finding of tectonics on Mars, would also seem to be dependent on resolution of these past controversies.

Would anyone have any updates to share on this front ?

Regards

Selfsim
2012-Aug-25, 12:19 AM
Found the relevant articles/studies.

The first article, (posted on 21st March, 2011 in Astrobiology Magazine), is called: "The Importance of Being Magnetized" (http://www.astrobio.net/exclusive/3856/the-importance-of-being-magnetized), by Robert Strangeway, Research Geophysicist, Institute of Geophysics and Planetary Physics and Earth and Space Sciences Department , UCLA.
He has written multiple peer reviewed papers leading up to what he says in the article: (available via his website, here). (http://www-ssc.igpp.ucla.edu/~strange/)

A key quote from this article is:

"My opinion is that the magnetic shield hypothesis is unproven"
...
"There's nothing in the contemporary data to warrant invoking magnetic fields". .. and then, not exactly surely who is making this point (but, again, from the same article): ..
If Strangeway had to guess, he would say the data will show that the difference between magnetized and non-magnetized planets will be slight. But he doesn't have any alternative mechanism for guarding our planet's water supply.

And then … "Earth's Magnetic field provides vital protection" (http://www.esa.int/esaCP/SEMXWW7YBZG_index_0.html), dated March 8th, 2012 by Olivier Witasse, ESA Mars Express Project Scientist … (not sure if a paper was written about the findings .. this one seems to only be a press release (?)):

“The shielding effect of the magnetic field is easy to understand and to prove in computer simulations, thus it has become the default explanation,” says Yong Wei from the Max-Planck-Institut für Sonnensystemforschung, Germany, who led the study.
...
Now, by making measurements during a planetary alignment when the two planets were being hit by exactly the same part of the solar wind, the team have proved it in reality.

Well, maybe … (??) … I would think the upcoming NASA MAVEN mission might be somewhat redundant if it was proven beyond the shadow of a doubt … (?)

Regards

dgavin
2012-Aug-25, 03:32 AM
No such thing as redundant experiments in science. It sort of goes like this.

Some experiments seem to prove (support) some theory. So after you confirm your own results, you publish a paper about it. Someone comes along and repeats the experiment on thier own. Seems to also support the Theory, they also publish a paper. Some years down the road, better dedectors are invented, so someone else reruns the same experiment, with more percise measurments. Again the results seem to support the theroy still.

And this goes on and on and on. Even in HS sceince they rerun old experiments, to teach how it's done, with soemtime the original dectors, or with the most modern. On a rare occasion with unexpected results that don't match the theory.

Selfsim
2012-Aug-25, 04:06 AM
Hmm .. see, I'm happy to leave the 'shield' hypothesis, 'up in the air', and suspend the 'need to know' whilst awaiting the unfolding of the story.

Others aren't however, and I've lost track of the number of times I've seen the 'magnetic shield' idea passed off as a 'slam-dunk reality'.

The problem would seem to be the absence of alternative explanations for why our local group of neighbouring planets display such diversity in something so easily observed (ie: their atmospheres/surface liquid contents). The wiggle space on this one, seems pretty tight though … the only thing I, personally, venture to think of, is that maybe the atmospheric volumes (and surface liquid volumes) of each planet were fundamentally orders of magnitude different initially (for no particular reason) … ie: the perceived escape rate, may not be the sole reason for the differences (??) That also throws planetary disc formation theory into question though …

The geological evidence for 'big past water' on Mars (for eg), is also a little difficult to explain, without there having been big liquid (water ?) there in the past, too … (I might also be way off target about this as well … best to leave it up to Witasse and Strangeway etal, I guess :) )

Interesting …

Cheers

Ara Pacis
2012-Aug-26, 06:06 AM
I think Mars would of had a different decay rate, as earths core, is the product of a merger of two planets, that formed the earth/moon system as we have today. Earhts core was recharged by that event, it was also reheated some, just from the merging of the two cores.Good point, but the LHB was afterwards, so would that later heating have been similar for Mars and Earth and would it translate into the core?


I would say yes to all of mars. Assuming the mantle was at 600c over all the planet before the impact events, that on average, it reheated to around 750c globally,
with the volcanic region being reheated to around 1200-1500c.Any idea how deep they'd have to drill. Not into the mantle, I hope.


1. No, not without a large body merger event that added to the surface and core material. 2. Only if we develop technology to add huge amount of radioactive materials into the core, in a human timely manner.I was wondering if it's possible a slab could be blocking circulation and if so, if it might move eventually on its own.

I saw an abstract recently for a paper observing a correlation between magnetic field superchrons and massive vulcanism a few million years later. I think the implication was that deep processes near the core-mantle boundary creating hot spots or involving slabs might be linked to the dynamo (assuming the the dynamo reacts rapidly while propagation to the surface takes a few million years I'm guessing). This is one of the reasons I wondered if there might be a cyclical field on Mars.

dgavin
2012-Aug-28, 02:14 PM
so would that later heating have been similar for Mars and Earth and would it translate into the core?

No, the reheating of Mars likely only affected it's mantle directly, where as the earth/moon forming event that mergered two planet cores into one, added a lot of heat and radiative materials into the core directly.

Any idea how deep they'd have to drill. Not into the mantle, I hope.

You'd want to get town to where them temp is about 400c-600c, so you might have to get near the mantle. The volcanic regions you might not have to drill down to far, as there is likely still some magma there.

I was wondering if it's possible a slab could be blocking circulation and if so, if it might move eventually on its own.
...
This is one of the reasons I wondered if there might be a cyclical field on Mars.

Mars does have achient volcanic deposits, and exibits magnetic striping in older materials. Indicating at one time it was fairly techtonicaly active and has a strong magnetic field. Those proceeses seemed to have stopped long before the volcanoes we can see now likely formed.

As far as a slab blocking flows, I think this might only happen only when the core is already lost a lot of heat. They have some hint that core cooling involves a crystalization process inside the core, if a core is already cooled down, and you add a much cooler slab material near it, it would likey trigger a rapid cooling event that could litterally cause the core to solidify maybe in only some thousands to a half million years. (there are many expiriment on your tube that will demonstrate rapid crytsalization events, including with just simple things like distilled water). The magnetic field would fade first, and the the techtonics would slowly wind down after that.

I suspect this is one way Mars cooling may have happened on Mars, the entire shut down of the core and techtonics taking only a few million years. But proveing that would take equipment we don't have available yet. Mars doesn't seem seismically activive enough to get siesmic tomology data on the core, so likely, that would require some sort of new detectors, maybe based on nutrino's, or a lot of explosives to imitate seismic events.

Personaly I shudder at the thought of blowing up large area's of mars just to answer how the core shut down really occured, it would take events in the 4-6 Magnitude range to get tomology on the core. Thats correlates to 30kiloton explosions, or larger. I think that even when we (people) get there, that this answer would have to wait for the right technology.

swampyankee
2012-Aug-28, 02:32 PM
While hunting for water and evidence of past life on Mars may be interesting, I think it would be much more worthwhile to get a seismic network there to investigate its interior. I believe Olympus Mons argues that there was no plate tectonic activity during its creation (at least where it's located), but there was obviously vulcanism, and there may have been some level of tectonic activity for many years after, possibly even until now. Looking at the interior of Mars would tell us a lot about how planets are put together. I'd like to see similar seismic networks on Mercury, Venus, and some of the Jovian and Saturnian moons, although I don't expect to see any of this unless I live well into my nineties.

Of course, a seismic network on Venus would be extremely difficult, especially if you wanted data for more than about 10 minutes.

Ara Pacis
2012-Sep-03, 07:49 PM
so would that later heating have been similar for Mars and Earth and would it translate into the core?

No, the reheating of Mars likely only affected it's mantle directly, where as the earth/moon forming event that mergered two planet cores into one, added a lot of heat and radiative materials into the core directly.

Any idea how deep they'd have to drill. Not into the mantle, I hope.

You'd want to get town to where them temp is about 400c-600c, so you might have to get near the mantle. The volcanic regions you might not have to drill down to far, as there is likely still some magma there.

I was wondering if it's possible a slab could be blocking circulation and if so, if it might move eventually on its own.
...
This is one of the reasons I wondered if there might be a cyclical field on Mars.

Mars does have achient volcanic deposits, and exibits magnetic striping in older materials. Indicating at one time it was fairly techtonicaly active and has a strong magnetic field. Those proceeses seemed to have stopped long before the volcanoes we can see now likely formed.

As far as a slab blocking flows, I think this might only happen only when the core is already lost a lot of heat. They have some hint that core cooling involves a crystalization process inside the core, if a core is already cooled down, and you add a much cooler slab material near it, it would likey trigger a rapid cooling event that could litterally cause the core to solidify maybe in only some thousands to a half million years. (there are many expiriment on your tube that will demonstrate rapid crytsalization events, including with just simple things like distilled water). The magnetic field would fade first, and the the techtonics would slowly wind down after that.

Thanks. I'm writing a story that involves colonization of Mars and was trying to figure out what was plausible. However, it's more a setting than a goal for the characters, so I don't think I'll be doing any planetary engineering in the scale of a core. I was just trying to figure out plausible ways that the planetary engineers that work in the background might be making Mars more habitable by getting at some method of recreating a magnetic field for radiation, getting at subterranean gasses for the atmosphere and trying to figure out glacial melt patterns and where the water would end up from topology and atmospheric transport. I'm wondering if the Hellas basin would fill up or if the highlands surrounding it would block moisture and cause much of it to end up in the northern basin. Do you know much about those or do you have a favorite resources?


I suspect this is one way Mars cooling may have happened on Mars, the entire shut down of the core and techtonics taking only a few million years. But proveing that would take equipment we don't have available yet. Mars doesn't seem seismically activive enough to get siesmic tomology data on the core, so likely, that would require some sort of new detectors, maybe based on nutrino's, or a lot of explosives to imitate seismic events.

Personaly I shudder at the thought of blowing up large area's of mars just to answer how the core shut down really occured, it would take events in the 4-6 Magnitude range to get tomology on the core. Thats correlates to 30kiloton explosions, or larger. I think that even when we (people) get there, that this answer would have to wait for the right technology.

I agree with the need for seismic sensors. I read that there's evidence of large quakes on mars in the recent geologic past and there's even been landslides more recently that have been photographed (though I don't know what the magnitude of a resulting quake is expected to be). If planetary engineers plan to bombard Mars with asteroids or icy bodies, they may use those impact for seismic imaging. Until the atmosphere thickens up enough or until they risk threatening then current or future colonization efforts, at which point they may switch to smaller impacts that only affect the atmosphere or poles.

astrostu
2012-Sep-04, 07:21 PM
Sorry, I've been gone a long time. What are the open questions still in this thread? I tried to read through and it seems like most have sort of been answered? I have some comments on what's been generally written in the thread ...

As for the initial paper, it's really the press release that emphasizes tectonics, his paper doesn't. There is no good evidence of plate tectonics ever having been present on Mars. As in, the crust fractured into several different pieces that move around.

Valles Marineris started as a tectonic feature not in the sense of plate tectonics, but fracturing as a result of the volcanic uplift from the Tharsis volcanoes. It has since been heavily modified by fluvial activity. Though Jeff Andrews-Hanna has a series of papers out suggesting a magmatic origin for Valles Marineris.

To my knowledge, the antipodal basin-volcano idea doesn't hold any validity, and the timing does not work properly. The Tharsis region of Mars where literally half (12 of 24) of the major volcanoes lie is one of the oldest features on the planet, the crustal dichotomy being pretty much the only large-scale surface feature that's older. Hellas basin (sorta near the antipode) is old, but only around 4.1 Ga, after the death of the dynamo, well after Tharsis got going. Argyre is one of the youngest 1+ Mm basins and is around 3.9ish Ga and also post-dates the Elysium volcanic complex, near its antipode. It definitely post-dates Apollinaris Mons, about 30°S of Elysium.

Heat is lost through conduction, convection, and radiative processes, and with Mars being only ~10% the mass but having ~20% the surface area of Earth, it's going to get rid of its heat faster.

Ara Pacis
2012-Sep-07, 06:24 AM
Thanks, I don't recall a timeline on the wikipedia article that made it as clear.

I've started a writing project, so I'm tossing around ideas and looking to get a good grasp of the geophysical potential of Mars. Another question I have, in case anyone would hazard a guess, is could we instigate volcanism on Mars to releases gases or would it not be possible?

astrostu
2012-Sep-09, 10:04 PM
Thanks, I don't recall a timeline on the wikipedia article that made it as clear.

I've started a writing project, so I'm tossing around ideas and looking to get a good grasp of the geophysical potential of Mars. Another question I have, in case anyone would hazard a guess, is could we instigate volcanism on Mars to releases gases or would it not be possible?

I'm not pulling this from Wikipedia, this is actually part of my research. :) Working with the group that's making the new global geologic maps of Mars - so all these stratigraphic relationships are in there - and I have a paper in review where I age-dated the ~100 craters with diameters >150 km, including several o the basins. Also I've published on ages on the Martian volcanos, so, yeah, I'm fairly familiar with the timelines, or at least what the majority of the evidence shows the timelines to be.

Not really sure how you'd be able to start up a volcano, at least not with current tech. If you're going to invent some future technology that you want to accomplish this, probably something along the lines of a robot that burrows through the surface into a magma pocket, or burrows down and just releases a @$#%@-load of heat that melts the rock, forcing it up through the path the robot drilled. At least, that's the first thing that came to mind.

Probably dropping a bunch of dynamite down a volcano like they did in the very controversial series finale of Dinosaurs wouldn't work.

Ara Pacis
2012-Sep-11, 06:40 PM
I'm not pulling this from Wikipedia, this is actually part of my research. :) Working with the group that's making the new global geologic maps of Mars - so all these stratigraphic relationships are in there - and I have a paper in review where I age-dated the ~100 craters with diameters >150 km, including several o the basins. Also I've published on ages on the Martian volcanos, so, yeah, I'm fairly familiar with the timelines, or at least what the majority of the evidence shows the timelines to be.

Thanks Astrostu, I didn't realize you were an expert. Any thoughts on what you'd like to see (or avoid seeing) in a fictional portrayal of Mars. I can't guarantee that anything I write will see the light of day, but I'm trying. But it's supposed to be hard science, so anything that may be physically possible and doesn't need magical tech might be used, although I'm assuming about a century's worth of R&D but no discoveries that redefine physics or anything like that.


Not really sure how you'd be able to start up a volcano, at least not with current tech. If you're going to invent some future technology that you want to accomplish this, probably something along the lines of a robot that burrows through the surface into a magma pocket, or burrows down and just releases a @$#%@-load of heat that melts the rock, forcing it up through the path the robot drilled. At least, that's the first thing that came to mind.

Probably dropping a bunch of dynamite down a volcano like they did in the very controversial series finale of Dinosaurs wouldn't work.

I was thinking of something using current tech to brute force it, perhaps drilling holes into key locations in a volcano then popping nukes at the bottom. I recall that the interior of the void that's created would be glassy, but I don't think it would be hermetic and on earth they tend to collapse creating a chimney, but with lower gravity on Mars, maybe not. Either way, The intent would be to create a zone of weakness, if possible, to allow trapped gasses to escape. Alternately, causing the magma to start moving again with the hope that it would release gasses. The problem may be the limited zone of effect of a single nuke, so it might require special designs or a series of them. Or maybe using the tube for a hyper-velocity impact would have a similar effect and/or more penetration beyond the drill's range. Or a thermal tunnel boring machine that uses nuclear heat to melt rocks as it digs (but then I'd have to figure out how to get hot rock pulp out from behind it).

Most of my questions involve thickening the atmosphere and figuring out the effects such as the pressure at various altitudes and the circulations of heat and precipitation. So, any suggestions people have are welcome and appreciated. :)

astrostu
2012-Sep-13, 06:27 PM
It's hard to say what not to put in other than blatantly wrong astronomy for no reason. My example is from the Transformers 3 movie where they just added a superfluous, "The far side [of the moon], also known as the dark side ... ." There was just no need for that extra part, and it was wrong wrong wrong wrong wrong! I guess that could be thought of more generally as, you don't need to try to bring in extra science that may be wrong just for the sake of it.

As for how to reactivate volcanoes using current technology, I'm really not sure how we could do it with current technology.

I found one paper that estimated a thermal release of 4*10^10 W of energy, averaged over the last 2000 years on Earth. Based on Wikipedia, that would be around 10 tons of TNT of energy per second. The biggest nuke ever exploded was the Tsar Bomba, 50 megatons of TNT. So it seems from these numbers that a nuke would be able to supply energy for a normal volcano on Earth, and though these do exist on Mars, keep in mind that the volcanos most people recognize on Mars are supervolcanos. The caldera of Yellowstone would be one of the smallest on Mars. The caldera of Arsia Mons is 10,000 km^2 (I know, I mapped it and counted nearly 50,000 craters on it).

I think you'd probably be better off, if you want to go with "current" tech, just going with a "new invention" and not go into the details of how it would work. It could be based entirely on current tech, not have a lot of technobabble (think Star Trek), but still do what you want without referring directly to only existing techniques. What you talk about in your paragraph of ideas would fit under this.

Ara Pacis
2012-Sep-14, 07:56 PM
It's hard to say what not to put in other than blatantly wrong astronomy for no reason. My example is from the Transformers 3 movie where they just added a superfluous, "The far side [of the moon], also known as the dark side ... ." There was just no need for that extra part, and it was wrong wrong wrong wrong wrong! I guess that could be thought of more generally as, you don't need to try to bring in extra science that may be wrong just for the sake of it.

As for how to reactivate volcanoes using current technology, I'm really not sure how we could do it with current technology.

I found one paper that estimated a thermal release of 4*10^10 W of energy, averaged over the last 2000 years on Earth. Based on Wikipedia, that would be around 10 tons of TNT of energy per second. The biggest nuke ever exploded was the Tsar Bomba, 50 megatons of TNT. So it seems from these numbers that a nuke would be able to supply energy for a normal volcano on Earth, and though these do exist on Mars, keep in mind that the volcanos most people recognize on Mars are supervolcanos. The caldera of Yellowstone would be one of the smallest on Mars. The caldera of Arsia Mons is 10,000 km^2 (I know, I mapped it and counted nearly 50,000 craters on it).

I think you'd probably be better off, if you want to go with "current" tech, just going with a "new invention" and not go into the details of how it would work. It could be based entirely on current tech, not have a lot of technobabble (think Star Trek), but still do what you want without referring directly to only existing techniques. What you talk about in your paragraph of ideas would fit under this.

I haven't seen that Transformer's movie yet, so I'm not sure what you're referring to. I want to keep it as hard science as possible without any new physics, but with some leeway in research and development and material science discoveries. I've read of a nuclear powered tunnel borer suggested for use on the moon, but that's a different environment from mars in the regolith, I think. Are your calculations to uncork a magma chamber or to create a magma chamber from nuclear bomb heat.

I want to thicken the atmosphere so that I can use large domed cities without worrying about them popping like a balloon or needing a spheroidal or toroidal design (Earlier habitats would use those, but I'm looking at a timeframe after 60-100 years of intense effort to terraform Mars. I also want to do paraterraforming with an air-bed like design (tufted) that is essentially flat over large areas. I'm trying to figure out how much atmospheric gas potential Mars has (I've heard estimates from 200 to 1000 mb) to figure out if I still need radiation shielding after the CO2, methane water vapor and other gasses are volatilized. Since Hellas basin is so deep, I was thinking it would be a good location for one such city and paraterraformed farm/ecosystem but I'm wondering how much water would accumulate there from direct melt and from rain. Or if most of the water would end up in the Borealis basin and then would the high ground level of the terrain surrounding Hellas basin be too high to allow rain from the north to reach Hellas, i.e. a rain shadow (despite the atmosphere's scale height being larger). I'm looking at a setting where ecopoeisis is just being attempted in the atmosphere outside of habitats, with both natural and genetically modified organisms.

astrostu
2012-Sep-15, 06:41 AM
You're getting pretty far beyond my field but I can offer a few observations:

- Lowest points are Valles Marineris, Hellas, and Lyot Crater (+50°N, +30°E -- I wrote a paper on it last year ;) ). VM was probably an outflow channel at some point and so may make a good place.

- Elevation around Hellas isn't huge, and the basin is large enough that it probably would not be in a rain shadow.

- I can't really comment on a "gas potential" for Mars - I really have no idea.

- Glass is a somewhat effective UV screen. From Wiki: "Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm." What if you did something like a double-paned glass structure, sticking ozone between two glass layers? Just tossing out an idea ...

- The very rough calculation of energy I gave you was more an example of the energy released during a volcanic event, so you'd need to pump at least that much in to get it to come out.

I think that's about it ...

Ara Pacis
2012-Sep-15, 11:57 PM
You're getting pretty far beyond my field but I can offer a few observations:

- Lowest points are Valles Marineris, Hellas, and Lyot Crater (+50°N, +30°E -- I wrote a paper on it last year ;) ). VM was probably an outflow channel at some point and so may make a good place.I was thinking about Valles Marineris, but I'd be worried about strong winds and water drainage making it diddicult. Maybe if there are hills above the waterline, but then I'd need to figure out how much water is available and how much of it would end up in the northern sea in Borealis Basin.


- Elevation around Hellas isn't huge, and the basin is large enough that it probably would not be in a rain shadow.Looking at the false color maps, it looks like the mountains surrounding Hellas are between 1-2 km above datum, so maybe that won't be high enough to cause a rain shadow, especially with a taller scale height on Mars.


- Glass is a somewhat effective UV screen. From Wiki: "Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm." What if you did something like a double-paned glass structure, sticking ozone between two glass layers? Just tossing out an idea ...I was thinking glass, although others (e.g. Zubrin) have suggested plexiglass without explaining why. I'd think it would be easier to create silica glass compared to PMMA (http://en.wikipedia.org/wiki/Poly%28methyl_methacrylate%29), and Polycarbonate might be better too.


- The very rough calculation of energy I gave you was more an example of the energy released during a volcanic event, so you'd need to pump at least that much in to get it to come out.

I think that's about it ...

Oh, I was thinking that some of the gas may be under pressure and just needs a route of escape to emerge on it's own in a slow release instead of an actual eruption, although both possibilities might be pursued. I was just thinking that if one or more volcanoes have magma still at pressure but too low to disgorge the plug blocking escape, that a drilled vent or fracture may trigger a release to commence on its own. Kinda like how a trigger pull on a gun is less force than is released when the burning powder forces the bullet out.

Thank you for your help, I appreciate it.

astrostu
2012-Sep-16, 06:32 AM
Just one comment at this point -- yes, the "rim" of Hellas is high, but remember that Hellas is a ~2000-km-diameter basin. That's a lot of real estate. Draw a circle around the highest points surrounding it and you're talking about a large area that water is going to run downhill from into Hellas.

Ara Pacis
2012-Sep-16, 09:43 PM
Just one comment at this point -- yes, the "rim" of Hellas is high, but remember that Hellas is a ~2000-km-diameter basin. That's a lot of real estate. Draw a circle around the highest points surrounding it and you're talking about a large area that water is going to run downhill from into Hellas.

If you don't want to answer more questions, that's cool. Do you have any resources you'd recommend for the other questions I have?

astrostu
2012-Sep-16, 11:02 PM
No, it's not that I don't want to answer more questions, it's more that you're getting into more speculative things that I don't know about or are up to your own literary license. If you have questions about Mars geology or surface processes, I'd be happy to answer more.