MARS OUTCROP SOURCE OF TINY SPHERES

JPL ^ | sol 13, opportunity, mars | JPL

[doodad]

Here is what wind typically creates in the desert. Compare to adirondack at the spirit site. (Someone teach me how to link to a web image, I know how on a hosted server). http://www.exploratorium.edu/origins/antarctica/fieldnotes/images/fventifact200.jpeg

[djf]

My mutt keeps the backyard well fertilized. I get a wide variety of fungi.

Nice warm spring day, I always have a pretty good crop of psilocybin by noon!

[Dan Evans]

"Seems to me, if it was ejecta, we'd see all sorts of other shapes mixed in." Exactly, and much greater variations in size as well.

But the spherical ones could have been sorted from the others by another process after being ejected. By wind or water.

[Bernard Marx]

Here is soemthing that looks similar. I made my wedding rings and a pair of earrings out of garnets I collected out of a weathered formation in Montana.

Good going! Gem garnets are my special interest and I collect and cut lots of varieties from worldwide locations. I used to collect matrix specimens like the ones in your image from the vast almandine garnet mica schist deposits throughout North Idaho, especially around Emerald Creek. They're definitely metamorphic!

The problem with your analogy is that garnet crystals aren't round. They crystallize in the cubic system and the ones in your image appear to be mostly cubes or octahedrons. That means those flat crystal faces would make them roll funny if you used them for marbles LOL. Do you have any idea what kind of garnets they are?

[doodad]

I really don't think so. See the note I had about the Murphy marble belt and the cannonballs. Obviously denser, more resistant material still rode on the surface of the clay. Drop marbles in a sand box, do they sink?

[Phil V.]

I turned my speakers all the way up, but still can't hear anything. Are you sure I'm logged in?

Have you tuned them to operate at Mars' reduced gravity? . . . also, reduce the air pressure in the room by 98%. Prepare yourself first by rolling a fatty and sharing it with a friend.

[djf]

The process on earth that brings rocks to the surface is the freeze-thaw cycle. Water, freezing under rocks, tends to lift them, thus providing more room beneath for more water to collect and freeze, thus lifting them further.

I know you're a geologist, I just post this for general knowledge.

[doodad]

The problem with your analogy is that garnet crystals aren't round

LOL Oh, I know they are dodecahedrons, just wanted people to see somewhat spherical objects in matrix. And here is the kicker..no crystal system is spherical. They were spessartine as near as I could tell and they had been rolled as they eroded creating transparent near spherical gems. Very nice quality garnets. You would have loved the one I gave my Dad one year as a paperweight. Almandine as big as a softball and perfect habit.

[Erik Latranyi]

Ball bearings from the BEAGLE Lander??????

[Far Right Field]

It is everything about gravity. And temperature. My 2 cents is from a giant impact (this crater obviously) as molten rock is blasted into the vacuum (or atmosphere) it will coalesce into a sphere, harden possibly (smaller ones) and fall back to the surface and begin the surface erosion processes. Subsequent seismic activity can account, along with liquid water, for almost any bizarre landscape geology over millennia.

If there was significant moisture or even a body of water then many of these various spheres would crack just as a hot marble will dropped in a glass of water.

I think you have partially broken the code. This stuff appears to be a mixture of volcanic ash, silicate spherules, and loosely consolidated as a result of standing water deposition. The reason I say volcanic instead of impact is the thickness of the deposit. Too much deposit for too few impacts. There seems to have been several episodes if I read the strata properly.

If all that volcanic ejecta was sent to low orbit due to less gravity, the spread or diffusion pattern would very large compared to an earth ash fall. However that statement assumes an Earth normal atmosphere. We know the present atmosphere is a fraction of what we have on Earth, but the question is, what was it during the volcanic activity on Mars?

So many questions, and answers are just beginning.

[Monty22]

aww, spacebunny eggs.

[djf]

Dunno... IMO, vulcanism is a hard sell, I've seen lots of pumice. And I have a couple of real nice samples of ejecta from Shasta, and while it is noticably red/orange in color, crumbly and porous, it's nothing like these.

[Erik Latranyi]

Check out this before/after picture from the spectrometer. It shows better detail and how easily the spheres get pushed down into the sand.

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040206a/moss_touch_movie_br.gif

[Dan Evans]

If they were solid, they would be denser than the sand, and would sink. They are hollow.

Actually, heavy objects don't tend to sink into sand. If they are spherical they will tend to stay on the surface.

I think they're solid. I see a lot of them that are broken in half with the flat side flush with the ground. You can tell which ones these are because they have no shading or shadow.

[Erik Latranyi]

Also take a look at this image. The detail is incredible.

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040206a/moss_touch_movie-B013R1_br.jpg

[LibWhacker]

<img src="PASTE THE URL FOR YOUR IMAGE HERE">

[LibWhacker]

I'm sorry . . . Is that what you meant?

[Erik Latranyi]

Sorry, I forgot. Check this out......

[clearvision]

Microscopic Imager:

[Erik Latranyi]

It's like the a meteor was melting on the way down and formed the spheres as it cooled, much like the way lead shot is made for shotguns.