Courtesy of The Guardian, we have a lovely high-resolution photo taken by the Mars rover Curiosity and some description of what it means. The first thing you’ll see in the photo is that this mountain has strata, and we’ll need an explanation for that, since on Earth strata are sedimentary rocks, and that means water.
NASA is showing off a high-resolution colour picture sent back by the Mars rover Curiosity, detailing the mountain where scientists plan to focus their search for the chemical ingredients of life.
The image reveals distinct tiers near the base of the three-mile-high mountain that rises from the floor of Gale Crater, where Curiosity landed on 6 August.
Scientists estimate it will be a year before the rover reaches the layers of interest at the foot of the mountain, 6.2 miles from the landing site.
From earlier orbital imagery, the layers appear to contain clays and other hydrated minerals that form in the presence of water, Nasa has said.
Previous missions to Mars have uncovered strong evidence for vast amounts of water flowing over its surface in the past. Curiosity was dispatched to hunt for organic materials and other chemistry considered necessary for life to evolve.
In this picture, the layers above where scientists expect to find hydrated minerals show sharp tilts, offering a strong hint of dramatic changes in Gale Crater, which is located in the planet’s southern hemisphere near its equator.
A lot of the geological excitement here centers around the search for hydrated minerals, which form only in the presence of water; this would give indisputable evidence for the presence of liquid water on that planet at some time, at least, and we all know why that’s interesting! (Mars has frozen water, of course—its polar caps—but the existence of water as a liquid is still controversial.
In this picture, the layers above where scientists expect to find hydrated minerals show sharp tilts, offering a strong hint of dramatic changes in Gale Crater, which is located in the planet’s southern hemisphere near its equator.
Mount Sharp, the name given to the towering formation at the centre of the crater, is believed to be the remains of sediment that once completely filled the 96-mile-wide basin.
“This is a spectacular feature that we’re seeing very early,” said John Grotzinger, a project scientist with the California Institute of Technology. “We can sense that there is a big change on Mount Sharp.”
The higher layers are steeply slanted relative to the layers of underlying rock, the reverse of similar features found in the Grand Canyon.
“The layers are tilted in the Grand Canyon due to plate tectonics, so it’s typical to see older layers be more deformed and more rotated than the ones above them,” Grotzinger said. “In this case you have flat-line layers on Mars overlaid by tilted layers. The science team, of course, is deliberating over what this means.
“This thing just kind of jumped out at us as being something very different from what we ever expected.”
Take out plate tectonics and the most likely explanation for the angled layers has to do with the physical manner in which they were built up, such as being deposited by wind or by water. “On Earth there’s a whole host of mechanisms that can generate inclined strata,” Grotzinger said. “Probably we’re going to have to drive up there to see what those strata are made of.”
Still waiting for the little green men to appear and attack the vehicle.
That excellent photo reminds me of nothing so much as an image a creationist might use to stump for “flood geology.” Do they think that Genesis flood struck Mars, too, I wonder?
yes, yes they do. just google flood mars genesis.
OMG you’re kidding! I’m speechless.
Moreover, some are trying to suggest that the one time presence of water on Mars and its subsequent disappearance is proof of a terrestrial Noahic flood.
While it is true to say that most stratified rock formations on Earth are involve the presence of water, there are also instances of rock strata resulting from successive periods of volcanic activity (e.g. http://www.sciencephoto.com/media/168838/view ), and we know that Mars has experienced a lot of volcanic activity in the past.
We shouldn’t get too excited just yet nut it is, nevertheless, a very interesting result.
D’oh!
“We shouldn’t get too excited just yet, BUT it is…”
@teacupoftheapocalpyse: Couldn’t agree more. While I’m sure NASA is right that these are sedimentary (probably from satellite spectroscopy), that image alone is not enough to say ‘water flowed here’. I’ve linked to
1) A picture of the Deccan lava traps in India:
http://www.treknature.com/gallery/Asia/India/photo206819.htm
http://www.princeton.edu/main/news/archive/S32/14/62G75/#comp00004e58f1530000006e2973bf
and 2) The Columbia Plateau:
http://kids.britannica.com/comptons/art-149596/The-Columbia-Plateau-is-uniformly-covered-with-basaltic-lava-flows
Not dissimilar at all 🙂
Those strata are more likely to be sub-aerial tuffaceous deposits rather than lava flows. We will just have to wait till Curo gets there. My personal guess is that they are hydrated sediments.
Given the number of strata depicted, that suggests a great many flooding / drying events over epochs. It also suggests the presence of a great deal of water over a wide area. We don’t yet know, for sure how mush water Mars had or when it dissipated, but we are fairly sure that it disappeared a very long time ago. We should also bear in mind that Gale Crater is only about 85km from Olympus Mons and both the Columbia Plateau and the Deccan Traps cover a far wider area than that , so we should keep an open mind about this until Curiosity can tell us more.
Based on Jerry’s quote, NASA said “stratified” not “sedimentary,” and Jerry was careful to say that the one doesn’t necessarily imply the other.
The quote was:
“… this mountain has strata, and we’ll need an explanation for that, since on Earth strata are sedimentary rocks, and that means water”
Sorry, but the logic is unfortunately wrong.
Some strata are formed in different ways:
* From huge flows of lava, and
* “Sub-aerial tuffs” (thanks dcm001) – that is from a volcano that blows pumice and other volcanic rocks into the air, which then fall to earth/mars. A typical volcano will do this many times, over time periods from hours to millennia, and each event causes a nice stratum graded from large rocks at the base to fine grains at the top. teacupoftheapocalypse posted a nice view of this from Santorini.
Oops – hit the button too fast. There are also strata formed from blown sand (thanks Kevin Alexander). In most cases, though, it needs water to transport minerals to cement the grains into a coherent bed to get the same stratification as seen from the photo.
What the strata are actually made from is unimportant at this point. What is important is that they present a fantastic opportunity to study the geological history of this part of Mars.
I’ve seen wind blown sand make layers like that.
Reblogged this on emmageraln.
I imagine from the description that the clays that is witness of water and can trap organics, lies beneath the more dramatic layered sediments.
An interesting recent climate theory for Mars is that chaotic orbital parameters are responsible for intermittent periods of snowmelt that can sediment aeolian transported dust. Very little snowmelt is enough, and it fits the rover observations (see the last figure of that post).
“Counterintuitively, at these high obliquity angles, the ice actually forms most stably around the equator.”
From the abstract:
“These requirements for melting are satisfied by 0.01 – 20% of the probability distribution of Mars’ past spin-orbit parameters. Total melt production is sufficient to account for aqueous alteration of the sedimentary rocks.”
In a year or two we may know how so many craters on Mars, like Gale, have been completely filled with sediments and possibly emptied again.
“Probably we’re going to have to drive up there to see what those strata are made of.”
Coolest Curiosity-related sentence yet…
I thought the exact same thing.
goose-bumps included…
I agree, but I deal regularly with a fellow who has several times remarked scornfully about the $2 billion which was spent to get pix of…dirt. I am afraid he is representative of a lot of aggressively incurious Americans who vote.
a year to cover 7 miles? why will it take so long?
1) curiosity top speed of 0.0852272727 miles per hour.
2) we have other things to check out first.
Additionally communication between Mission Control and Curiosity is asynchronous, which means that a conversation between the two takes place intermittently over time. The one-way communication delay with Earth varies from 4 to 22 minutes, depending on the planets’ relative positions, with 12.5 minutes being the average. Thus, each of the “other things to check out first” could take hours or even days, dependant upon the complexity.
Curiosity has not been sent with a set game plan, but to discover more about what is there and to take further action where need be, based upon what it finds.
Not to mention that all this has to happen when we have daylight…
Well, on Mars!:) Not sure what that means for Curiosity operations, but there’s an ap for that!
http://www.sunlightandtime.com/mars-clock.html
well, when your SUV has no lights – its ‘day’ becomes ours where driving is concerned…
Another difficulty presented when communicating between Mission Control and Curiosity, is that Curiosity has a two tiny transmitters, a 15W X-Band radio and a 9W UHF. Compare this to the power output of even a local radio station on earth, which could be 50kW or more, and think how easy it is to lose the signal in your car as you drive around. This means that Mission control has to use a huge antenna and the only one up to the task is the 70-metre DSS14 dish in the Mojave Desert. Which means that communication is only possible when the two are in line of sight.
Additionally, the amount of available communication time is reduced because the two planets’ rotations are out of sync as the Mars day is 37minutes longer than the Earth’s
oooooh, geology pron!
For me, this is the field trip of a lifetime.
Correct me if I am wrong, but isn’t Gale Crater an impact crater? Hence if Mt Sharp was a result of that impact, the ‘sediments’ (sub aqueous or not) are going to be all over the place, compared with the country rock outside the crater?
impact happened about 3.5 billion yrs ago – sedimentation occurred after – one theory at least
From what I’ve read Mt Sharp isn’t a “central peak uplift” resulting from the impact that caused Gale Crater. I suppose that the original uplifted peak is hidden inside though, but is much smaller than the mound as we see it today
HERE’S a graphic showing how a 154km-wide hole in the ground can end up with a mound in the middle that’s taller than the crater walls ~ it takes 2,000,000,000 Earth years to get a cake that looks like that it seems
This link:- When Gale was young is a fine read ~ the ‘evolution’ of a Martian crater over billions of years is far more complex than say a lunar crater due to the presence of water, an atmosphere & possibly tectonics too
Liquid deposited sediments are horizontal. The tilted strata seen in the photos could well represent debris from volcanic activity or large meteor strikes, not to mention wind reworking of dust on slopes. Since the sun was less bright in the past, it seems improbable that liquid water was present then but is absent now. There is little chance that life (as we know it) could have evolved on Mars. Panspermia of Kelvin, Hoyle and cia also seems unlikely. So far as I am aware, no minerals have been found in the solar system greater than 4.56 billion years old, i.e., possibly from other worlds. It will be interesting to follow NASA discoveries as they confirm what seem to inevitable facts. It will be well worth the price.
In the absence of a spirit-level, or other such device, in view, it is impossible for us to say whether Curiosity was on an incline, which would have tilted the image, when the picture was taken.
While liquid deposited sediments are (almost) horizontal at small scale, they frequently get tilted, so I would have to disagree with your assertion.
Some tilt mechanisms that are possible here are:
* Regional subsidence of the underlying sediments. Caused by either uneven bedrock (Leaning tower of Pisa) or by different types of underlying sediment (clays in some area, sandstones in others, for example)
* Volcanic intrusions
* Tectonic movements (and some possible ones have just been identified on Mars).
On a large scale, sediments are not level. Consider a river delta – as the river water flows out to sea, the heavier material gets deposited first and in large amounts. The further away you are from the delta mouth, the less sediment gets deposited. This leads to a slope of several degrees inclination.
Further complications are erosion causing channels on the surface and then subsequent infilling.
Basically, it’s complicated.
As for pre-historic liquid on Mars, there are good quality observations from Spirit and Opportunity, and also from Mars Global Surveyor, Pathfinder, Odyssey and Reconnaisance Orbiter of minerals that can only be laid down with large amounts of liquid water. And the newer satellite imagery shows geological features that are more than highly suggestive. See http://en.wikipedia.org/wiki/Water_on_Mars for more details.
I am with you on Panspermia, though. But it *would* be interesting to get extra-solar system particles 🙂