[meteorite-list] CAI animations! 3-D internal Metal!

From: Martinh <martinh_at_meteoritecentral.com>
Date: Tue Feb 22 17:34:16 2005
Message-ID: <7c8b4c1a0ef9b979aa211f2505158d9f_at_isu.edu>

Hi All,

I was exploring the web for more CAI information and found the
following animations! Check out the CAI fly-through. One question
though; the 4.5mm measurement bar in the static tomographic slice seems
odd. If the bar is 4.5mm long, the the CAI is 2mm wide at best-hardly
anything to get excited about. Did I miss something?

Anyway, here is the text and links to the animations....

Oh, and one for the record books: don't miss this Krymki LL3.1
fly-through at:
http://research.amnh.org/users/debel/tomo1/Krymka1_Z.mpg

Here are two links with the metal isolated in a piece of Renazzo. WAY
COOL!
http://research.amnh.org/users/debel/tomo1/Renazzo/chon2-v2.gif
http://research.amnh.org/users/debel/tomo1/Renazzo/
chondrule_2_cropped_2.avi

I'd love to see a nice mesosiderite go through the same treatment.
Wouldn't it be an amazing piece of art to have a static model of the
interconnected metal veins in a meso isolated from the stony matrix?
Like a wire-filled ball showcasing the distribution of nickel-iron with
accurate relative position and concentration density.

Oh, expect long downloads with dial up connections. Some of these files
are big.

Enjoy. Dream.

Martin H


This large Type B Ca-, Al-rich inclusion (CAI) was fortuitously found
in a cut piece of the Allende (CV3-ox) meteorite at the American
Museum of Natural History. A small corner of the CAI had been cut
away, but the rest of the object is intact. The entire object was
imaged at the Advanced Photon Source in 2001, at a resolution of 12.6
microns/pixel. At this resolution, large melilite crystals are visible
due to their high Ca content (melilite: Ca2Al2SiO7-Ca2MgSi2O7), in
contrast to Ti-, Al-rich pyroxene (fassaite). The melilite crystals
appear to grow inward from the rim. Small spinel grains are not
resolvable at the resolution of these images.

Fly-through in z direction.
  Bright material is metal/sulfide. Also notice the void spaces in the
interior. Ring artifacts result from defects in the CCD camera which
obtained the images.
http://research.amnh.org/users/debel/tomo1/AlCai1/AllendeCAI-2_Z.mpg


Static tomographic slice with scale bar and description of features.
  Many features of this CAI are shown in this "slice" through the
tomographic data set. Note that the black/white density range is
reversed in this image, compared to the fly-through movie. The entire
object is shown, except for a small slice at one corner, which was cut
off the sample when the meteorite was sectioned. Locations of SEM
photos are shown. These images are not yet posted to the web.
http://research.amnh.org/users/debel/tomo1/AlCai1/Al1-CAI-300map1.jpg


Animation: dense metal grains (gray) are highlighted.
  A portion of the CAI is shown. Note the outer surface texture, the
relation of metal/sulfide grains to the outside of the CAI, and the
void spaces in it.
http://research.amnh.org/users/debel/tomo1/AlCai1/B1-a-ch1a.gif
Received on Tue 22 Feb 2005 05:32:59 PM PST