Dear listmembers,

        I hope someone can help me understand something I'm curious about.
I don't usually deal with marine limestones, but I am collaborating with a
colleague on a section of Paleozoic carbonates.  Before extracting CO2 by
conventional means for isotopic analysis, we ran powder XRD patterns to
determine which samples were dolomitic.  In the process, we observed that
peak heights were in the right place, but their intensities were about 10 x
smaller than that of a ground calcite crystal run at the same time.  These
samples are fairly clean [<10% insoluble material].  Any ideas as to the
source of the diminished peak heights?


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Steve Nelson
Dept. of Geology
S389 ESC
Brigham Young University
Provo. Utah  84602

voice:  1-801-378-8688
FAX:  1-801-378-8143

"INTEL INSIDE" is a warning label
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