Check out these microscopic images of Martian rocks from the Opportunity landing site:
IMNAGeologist, but the microscopic images sure look like limestone to me. Kinda even looks like coral! If it is limestone or any other type of sedimentary rock, then the rover missions are unqualified sucesses. If it is coral or something similar, it would be the Grail, wouldn’t it?
Anybody with more geoglogical knowledge than I care to specululate as to what we’re looking at here?
I’m no geologist, but to my completely untrained eyes those look an awful lot like wind-sculpted rock.
IANAGeologist, either, but I’ll show these to my geologist colleagues tomorrow. I’m not sure about coral in the microscopic images, but they certainly appear weathered. And the context image shows many small rocks that were transported to their present location by something (water, wind, gravity, vulcanism or meteor impact come to mind). If it is a limestone, we’d certainly be thinking of the presence of water, oxygen and life.
Another non-geologist checking in. My brother-in-law, who is something of a geologist, thinks these rocks look an awful lot like some bioturbidites that he and my daughter found near his parents’ house in north-central New Mexico when she was collecting rocks for her science fair project. Their land is pretty unusual, geologically speaking, and we plan to send some rock in to NASA through their “Schoolhouse Rocks” program.
According to Space.com it isn’t limestone.
The most interesting part is the round piece that isn’t the same material as the surrounding stone. That’s what they’re investigating.
sorry, IANAG, and I wouldn’t know limestone if it bit in the butt, so I’m not really adding anything here, but I just had to say: damn, that’s cool.
The layering sure look like these rocks formed in water to me, and the pattern of weathering looks either wind-sculpted or like something you would see on a seashore. But I was an English major, which is why I started this thread.
InternetLegend, what are bioturbidites? (anyone else who knows what they are is welcome to chime in as well!)
I was more intrigued by the rocks themselves, but it seems that the NASA folks are looking at the little sphereoids. Although it looked boring at first, the Opportunity site seems to be more geologically interesting than the Spirit site.
I agree, gonzoron, this is super cool! Microscopic images from Mars!
Well, IAA geologist, but certainly not a planetary one. MLS, yes, it does look wind sculpted but in addition look at the smaller “string of pearls” like features that can been seen throughout, albeit on a much more subtle scale. I’ve seen those on carbonates before but, admittedly, also on metamorphic and even igneous rocks as well.
To me they look a great deal like some of the diagenetic features I did my carbonate thesis on. For once I’m not interested in their reservoir potential. 
This is going to sounds stupid but…we need to remember that Mars is not Earth. That rock has been scoured by dust for thousands and thousands of years. A typical dust devil lifts dust averaging 10um in diameter. Typical Earth dust is between 40 to 60 um. The erosion produced by such fine particles might wind up looking like water erosion.
It’s still damn cool and I’d love to know what those spherical nodules are.
Hey anyone know how to get greek symbols to show up properly?
Regarding turbidites, they’re generally found around continental margins and can perhaps best be described as a submarine debris flow deposits. You’ll get a lot of sand and silt accumulate on a slope until the degree of repose is surpassed and then it’ll break loose much like an avalanche. They’ll pick up everything, including biota, in their path and redeposit the matrix in thinner, fan-shaped deposits.
IAAA (I am also a) Geologist, but a hard-rocker, so I’m no use here. Looks like siltstone or mudstone to me.
Pictures of turbidite deposits:
http://www-geology.ucdavis.edu/~GEL109/SedStructures/Turbidites.html
Scroll down for some pix of a Bouma Sequence (turbidite deposit):
http://www.es.usyd.edu.au/geology/people/staff/prey/FieldTrips/SouthCoastExcu02/DayOne.html
IAAA (I am also a) Geologist, but a hard-rocker, so I’m no use here. Looks like siltstone or mudstone to me.
Don’t you just hate it when you say “Ctrl-C” when what you mean to say is “Ctrl-X”?
