At MURR's Archaeometry Lab, we analyze for about 30 elements, generally at a sensitivity
level of parts per million by weight. This means we can distinguish
one microgram of an element among a gram of multiple
elements, or at the level of one-millionth of the gram—and that
is highly sensitive. [For some elements we take it to one part per
billion!] We then pair two elements together to produce a
graph. The possible pairings for 30 elements are nearly 900, but
our scientists usually have a good idea which pairings will yield
relevant information. It is the clusters of data points (concentrations
of the two elements) on the graphs that we try to match—an obsidian
artifact from a particular obsidian quarry will have the same level
of concentration of those two elements. If we put the artifact graph
on top of the source graph, the clusters would appear in the same
place for each. The same holds true for matching the pottery sherd
with its original clay soil source.
Other possible applications for NAA in archaeology include studies
of prehistoric technology (i.e., determining how materials were
made), studies of the uses of different artifacts, and studies to
determine the authenticity of questionable artifacts.
The Archaeometry Lab at MURR supports faculty and student research
efforts from several University of Missouri-Columbia (MU) departments,
including Anthropology,
Art History and Archaeology,
Geography and
Geological Sciences.
But it is also a national, even international,
resource. For well more than a decade the National Science Foundation
(NSF) has provided significant funds to make MURR's Archaeometry
Lab accessible to faculty and student researchers at educational
institutions throughout the country. One aspect of the NSF program
brings graduate students from other universities to MURR for a several
month-long internship and invaluable hands-on experience. Usually
they bring samples from archaeological digs to analyze for their
thesis research. Under the mentoring of MURR faculty and staff,
they learn how to prepare the samples for irradiation, perform the
analytical techniques, evaluate the results, and then present their
findings in a professional setting.
Some examples of archaeological NAA studies taking place at MURR
are on the following pages.
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