CHAPTER 12
In-situPreservation of Waterlogged
Archaeological Sites
DAVID GREGORY AND HENNING MATTHIESEN
Department of Conservation, Archaeology, National Museum of Denmark, PO Box
260 Brede, DK-2800 Kongens Lyngby, Denmark
1 INTRODUCTION
Increasingly, newly discovered archaeological sites are being preserved
in situ, as opposed to being excavated. Many factors are influencing this
trend, including the high costs of recovery coupled with the conservation and
subsequent curation and management of recovered remains in perpetuity.
Furthermore, it may not always be desirable, or necessary, to excavate a site.
Yet, as part of the cultural resource it should be preserved or managed in situ.
Thus, there is an ever-increasing need to develop an alternative to conventional
conservation. In situpreservation is a form of preventive conservation and has
become a common solution to the management of archaeological sites in
wetlands and on underwater sites. This solution is, however, only viable if we
are able to understand the threats against the archaeological remains and con-
trol the environment at the site. Deterioration cannot be completely avoided
and therefore absolutepreservation in situis not achievable. All sites are
dynamic, continuing to form in the sense that deterioration processes keep
on altering the material remains albeitat slow, often imperceptible, rates.
However, conditions conducive to the preservation of archaeological arte-
facts can be assured by a sequence of environmental monitoring combined
with the analysis of artefacts from the site and the study of the deterioration
of analogous modern materials. In this way the processes of deterioration, state
of preservation and the future threats to artefacts, or a site, can be identified.
This will enable a risk assessment of a site to be made. Based on this, there are