Allende Large CAI #1

Allende CAI #1 (AlCAI1)

Background

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 10.24 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.

Index (links) for whole and sub-pieces:
tomography of whole object
Section A
Section B
Section C
Section D

Tomography (entire CAI)

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. Data is at 10.24 micron/pixel resolution. There is a slight break in contrast across the x- and y- slices, because the data was obtained in two sequential sets of images, stacked in z. Because of subtle vertical variations in beam intensity, the break between vertically stacked data sets is slightly visible.
"Fly-through" movies in MPEG format (resolution may be degraded):
X movie: (7.53 MB) Fly-through in x direction.
Y movie: (9.36 MB) Fly-through in y direction.
Z movie: (13.95 MB) Fly-through in z direction.
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Stacks of TIFF format slices at full 10.24 mu/pxl spatial resolution, 256 grayscales (8-bit):
X slices, n = 446.
X slices, n = 566.
Z slices, n = 850.
Virtual slice of CAI: 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.
Metal Animation 1: 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.

Section A

Section B

Section C

Section D

Large version of this figure (TIFF 300dpi).

Section D

Index (links) for data:
tomography (__ micron/pixel)
X-ray intensity (entire)
sub-area index map & links
microprobe data (w/ maps)
laser-ablation ICPMS data

Tomography (Section D)

Tomography data was obtained in 2002, at 4.4 microns/pixel spatial resolution.
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.
"Fly-through" movies in MPEG format (spatial resolution is degraded by 2x):
[NOTE: High aspect ratio mpegs in x and y directions may not play on all movie players.] X movie: (large file) Fly-through in x direction.
Y movie: (large file) Fly-through in y direction.
Z movie: (large file) Fly-through in z direction.
Stacks of TIFF format slices at full spatial resolution, 256 grayscales (8-bit):
X slices, n = 280.
X slices, n = 410.
Z slices, n =1471.

Whole Section Maps (Section D)

X-ray intensity maps (2 micron/pixel, entire surface; BSE for this mosaic did not run)
Elements (original mosaics): Si, Si, Ca, Ti, Mg, Al
Composite three-element overlay (Red-Green-Blue): Mg-Ca-Al, Si-Ca-Ti, Si-Mg-Ca, Ti-Ca-Al
Miscellaneous: BSE + 3 RGB (300dpi)

Sub-area Mapping (Section D)

Large version of index map (TIFF 300dpi).

Sub-regions (x-ray EMP maps): C1D1 (2 mu): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D2 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D3 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D4 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D5 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D6 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D9 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... FTC, MCA, TCA
C1D10 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D11 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
C1D12 (_ mu, 512?): BSE, Al, Fe, Ti, Ca, Mg,... MCA, TCA
CAI30 to 35 (all 1 micron/pixel, frame 512 x 512):
CAI30: BSE, Al, Fe, Na, Ca,... SCF
CAI31: BSE, Al, Fe, Na, Ca,... SCF
CAI32: BSE, Al, Fe, Na, Ca,... SCF
CAI33: BSE, Al, Fe, Na, Ca,... SCF
CAI34: BSE, Al, Fe, Na, Ca,... SCF
CAI35: BSE, Al, Fe, Na, Ca,... SCF

EMP Data (Section D)

(to be added)

LA-ICPMS Data (Section D)

(to be added)

Acknowledgments

Use of the Advanced Photon Source was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38. Use of the GSE-CARS beamline, University of Chicago, is gratefully acknowledged. This work is supported by the American Museum of Natural History.

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Last modified October 17, 2005.