1 Paleoradiology: History and New Developments - Academia.dk

58 Chapter 3 The Taphonomic Process, Human Variation, and X-ray Studies
Fig. 3.6. Xeroradiographic image of ancient Chinese lacquerware,
with internal detail clearly visible. Courtesy of Jacqui
Watson, English Heritage
Fig. 3.7. Iron Age bread roll (burnt), x-rayed to show the inner
granular detail
ted plant debris, and x-rays provide an ideal method
of scanning such material before any specimens are
selected for further laboratory analysis.
3.3
Radiological Aspects of Zooarcheology
Paleontologists have made use of radiographic techniques
more enthusiastically than zooarcheologists
in the past. Indeed, in some instances, it has been a
highly successful tool in revealing the less commonly
seen finer anatomy of organisms. For instance, from
fine shale of the Ordovician and Devonian periods,
the pyrite-preserved soft parts of trilobites within the
shale were revealed by x-ray (Robison and Kaesler
1987). An ideal x-ray of a fossil demands a balance
Fig. 3.8. Ancient coprolites, containing some contrasting
structures
between sufficient penetration through the fossil and
matrix (needing high voltage) and sufficient light/
dark contrasts (needing a low kV and a long exposure
time). Depending on the lithology, fossil hydroids,
graptolites, fish, and other vertebrate species have
been revealed successfully by this technique (Harbersetzer
1994; Longbottom 2005). Heavily fossilized
skeletal material can present special problems with
regard to obtaining sufficient detail of the internal
structures, especially if the interior of the bone is invaded
by siliceous deposits (Fig. 3.9).
Although it is mainly vertebrate remains that have
received radiographic study in archeology, it should
be mentioned that there is clearly potential when considering
invertebrate remains, for the extraction of
information by means of x-rays. There is certainly a
need for colleagues specifically working with invertebrates
to consider the potential value of radiographic
techniques, and perhaps undertake experimental
investigations in order to evaluate what might be
achieved with some kinds of archeological material.
For instance, would it be possible, by means of digital
x-rays, to detect not only insect damage, but also the
actual animals buried within other organic remains?
For instance, insect damage to bone might be confirmed
radiographically by detecting the insect remains
deep within the calcified tissue. However, experiments
would be needed to establish that insect structures
could be identified within bone or other tissue.
Similarly, insect damage to mummified remains is