[meteorite-list] Sedimentary Martian Meteorites (& a little gorgeous Ad).

From: Martin Altmann <altmann_at_meteoritecentral.com>
Date: Thu, 24 Mar 2011 15:17:20 +0100
Message-ID: <003d01cbea2e$30b1e070$9215a150$_at_de>

Good Morning Carl,

I think, I'm very on topic.

I've got the impression that you speculate, that there must be sedimentary Martian meteorites laying all around
and that the only obstacle, that they are not recognized as such, would be that the researchers refuse to measure stones, which don't show properties, they know from known meteorites. Respectively that they would do so only, if they would get money for that.
And that you suggest, that we have therefore to change something in the existing system, which until now had brought the stones from the soil they're slumbering on into the Meteoritical Bulletin.

So I was giving you a hint, that the system was so far able to recognize meteorites as meteorites, also if they oppugn our all traditional viewing habits.
Decisive for a meteorite being recognized as a meteorite is not only that, what you feel to be the only obstacle, that a lab would refuse to analyze a stone,
at least as decisive is, that someone has the idea, to pick up such a stone, although it is not looking like meteorite in the field, because he thinks, despite that, it could be a meteorite.
And be aware, that no one in the field has a saw, a microscope, a microprobe at hand, neither with Blaine's magic machine you'll be able to identify such a stone being from Mars.
And second, after the stone is picked up, it has to survive the long chain of going through many hands, before it ends in the lab, without that any hand will throw it in the dustbin.

That this obviously works, therefore I gave you 3 examples,

Where about you say:

>They actually do look like meteorites to me and you both.

For you maybe, for me they don't look at all like meteorites and I dare to guess, that 99.9% of the experts,
no matter whether scientist or private expert, wouldn't have picked up these stones in the field.

And the second thing is, one has to speculate about odds and probabilities, how present such sedimentary Martians are on Earth - especially if one like you wants to have hand-in changes in the system of meteoritics, that such stones could be recognized at all.

And there you have to juggle with the numbers we have.

Absolutely unsuspicious and unbiased, and there you will agree, are the observed falls.
1200 we have in history. No sedimentary stone was among them. But anyhow 4 Martians.
Hence 0.3%.

Well. Currently the Bulletins have 52,524 entries/numbers of meteoritic finds.
98 entries are Martians. 0.2%

That's the score list of 196 years.

Obviously it is in general devilishly difficult to find a Martian at all.
(as meteorites in general are not easy to locate).

Perhaps a little visualization...

Herb, Stefan...forgive me, the Austrians can be sometimes somewhat idiosyncratic people.

The athlete in the picture applies for the title: "Austrian Giant".
In the right and in the left hand, he carries a little suitcase made of concrete.
Each of the suitcases weighs 130 kg. Concrete has a lower density than Martian rocks.
All Martian meteorites we have identified currently on Earth during the last 200 years,
have a combined weight of 100kg.
So I hope that little comparison works.

Martians all in all so far we have a little suitcase full so far on Earth.
http://www.flickr.com/photos/32845189 at N06/4721533075/

(Keep that in mind, if you get one offered or if you see some on ebay and if a couple of 100 bucks a gram seem to you to be a horrendous price. Or make a game, to keep the kids on the backseat calm: Find something, which is as rare as Martian meteorites).

Let's go further.
Now these 98 entries represent 56 fall events, 56 different meteorites.

Consider furthermore, that science found out, that these 56 meteorites weren't hurled into space by 56 different impact events on Mars, but that the number shrinks even more, because you can subsume them to launch-pairings.

Now these are igneous Martian rocks, which - there you see no problem - are recognized and identified without problem in the course all meteorites go.

Now you can speculate - are sediments in the upper Martian crust prevalent or igneous rock?
There I'm no expert - (I believe to remember, that sediments were observed on Mars not so often..).

So all in all. We have a few spot test from the Red Planet in form of a handful Martian meteorites here on Earth. Igneous Martians we can recognize, they are found and recognized, but a find of such a Martian belongs to the quite most extraordinary rare events, which one can imagine.

Now you have to ask yourself - the process of finding a stone is always the same.

Even IF we would know, how a sedimentary Martian would look like, even IF a sedimentary Martian would have a wonderful black fusion crust, even IF sedimentary Martian meteorites would be nearly as frequent or abundant like igneous Martian meteorites,
then it would be still an extremely hard nut to crack to find once any!

And there you have to see, what that would mean for your dissatisfaction.
What do you want to change in practice, what makes sense?

If the probabilities to find a Martian sediment are so extremely low,
does it make sense to make serial analyses at more or less random on sediments, whether they contain cosmogenic nucleids to find out, whether they were in space?
Draw a circle of a mile around your home, if you would measure each and every sedimentary stone there, I fear, that would cost as much as the Apollo program... and I wouldn't directly expect, that a Martian would be among them.

I think, it makes no sense.

(Btw. why are you always so fixated on fusion crust? There are other properties. Take the signs of shock effects. And the Martians in general seem to be all quite shocked. Some have even shock veins, and if you look at the known ones - there is no type else, which would have so much maskelynite.
And another "btw.": If you would have to do with NWA meteorites, you'd know, that it is certainly not so trivial, as you might think, that the people involved would care only for stones looking like typical meteorites! On contrary! Quite the most often question posed is, whether a stone is a meteorite at all or only terrestrial. Harvest the pictures of the Meteoritical Bulletin database, the EoM, the list archives and you will be flabbergasted, what for weird rocks people had identified as meteorites!).


Where could we get our first sedimentary Martian meteorite from?

1.) We can wait, until with sound and light such stones will fall on our head.

2.) We have to wait, until once in one of the parts of the Antarctic hunting grounds, where you really have nothing else than sheer ice, such a stone will be once found.

3.) We wait until the best experts we have on the planet will bring such a stone.
Who are they? By faaaar: the most exotic and the most of the exotic meteorites of the World meteorite inventory came and are coming from Sahara. Say the Meteoritical Bulletins.
The anonymous hunters, the dealers, the collectors and curators financing them, and finally the scientists classifying these finds - better and more efficient (also cost-efficient) experts do not exist.
So I guess, that would be the most promising of those 3 points.

But for that, Carl, we need: Paaaaaaaaaaaatiiiiiiiiiiiiiiiiiiiiiience!


Best!
Martin





PS. Uh, the Heirs came down with such a bad cold. Oooh. And despite that, I tortured myself in writing again such a lengthy post. So I have to add an AD. An urgent one.

1.) Rather by chance, we found still 2 nice cuts of the very important NWA 5990.
The only depleted permafic Martian diabase. Fine fresh, unpaired, highly unusual.
Unfortunately small tkw.
0.199g and 0.256g they have.
Not being pushy - but you won't get that again anymore. They are the last. Not a crumb left.
After they're gone - that extremely special Martian will be over and out, gata & finito, aus!

2.) And 3 slices with fusion crust, around half a gram of the sensational NWA 6162,
which is currently introduced on the LPS-conference, are left. Also ultimate specimens of that unpaired Martian. The Martian, which is so sensationally fresh, that not only we believe, that it is the best basalt,
a collector ever could own - just ask those, who are happy owners of a slice.

All not at horrendous prices, but even at a slightly reduced rate.
Really last chance. (And ebay would make them only unnecessarily expensive).



Addendum:
Last time where we gave the new abstracts about the recent Martians,
We weren't aware of.. here for your records,
A comprehensive 18-pages work about NWA 5789 was published in January in MAPS:

Juliane GROSS, Allan H. TREIMAN, Justin FILIBERTO, and Christopher D. K. HERD:

Primitive olivine-phyric shergottite NWA 5789: Petrography, mineral chemistry,
and cooling history imply a magma similar to Yamato-980459

http://www.lpi.usra.edu/science/treiman/Gross5789.pdf

 












-----Urspr?ngliche Nachricht-----
Von: cdtucson at cox.net [mailto:cdtucson at cox.net]
Gesendet: Mittwoch, 23. M?rz 2011 16:53
An: Martin Altmann; meteorite-list at meteoritecentral.com
Betreff: Re: [meteorite-list] Sedimentary Martian Meteorites

Martin,
As always, I like your input but please look at the subject line on this thread.
We are talking about Sedimentary rocks here.
All of these planetary rocks you refer to are igneous. Not sedimentary. They actually do look like meteorites to me and you both.
Sedimentary rocks might have layering and veining, sand, mica, and too many other oddities to mention here.
But the point is that until these Scientists are paid to test all ice field finds and not just the igneous ones, we may NEVER find any sedimentary meteorites. We need to re-think what we are looking for,
We know these rocks exist on Mars. So, we know they exist in meteorites.
I offer you the challenge again.
Ask any Scientist if he is EVER willing to study any rock that resembles a sedimentary rock that lacks fusion crust.
His / her answer will be NEVER.
I recall in a post seeing a pile of meteorwrongs posted by a Scientist that were found in the ice fields. Those would be good candidates to re-check.
Thanks.

Carl

--
Carl or Debbie Esparza
Meteoritemax

Received on Thu 24 Mar 2011 10:17:20 AM PDT