Ανασκαφή Δισπηλίου 2002 : το ξύλο βγήκε από τον παράδεισοPart of : Το Αρχαιολογικό Έργο στη Μακεδονία και στη Θράκη ; Vol.16, No.1, 2002, pages 649-662
Dispilio 2002 : “wood came off heaven"
The research team working in the Neolithic lakeside settlement of Dispilio has met a considerable archaeological problem, which has to do with the reveal, exposure and conservation of a highly demanding archaeological material that is waterlogged wood. Archaeological waterlogged wood possesses a special position among the categories of archaeological material with particular archaeological significance for a more thorough understanding of the past cultural behavior. A multidimensional body of information is hidden away within the study of waterlogged wood, concerning details about species exploitation and selection, woodland composition and management practices, chronology, climate and developments in carpentry technology.The wetlands yield a great variety of well-preserved finds, which usually perish on dry land, but here they remain in a very good condition under water for thousands of years. Their preservation is due to the anaerobic conditions, which prevail in wet sites and hamper decomposition of organic materials.However, even in wet sites under excavation, wet wood, being susceptible to damage by physical means as well as by exposure to the air begins to decay and suffer irreparable loss of valuable information through its exposure.For this reason the conservation treatment of wood in the laboratory, such as PEG treatment, air drying, of freeze drying is essential to stabilize the shape, dimensions and surface features of the wood item so that it may be kept safely without further change in the normal indoors environment of a museum store or display area. Of course, no conservation process can restore the wood to its former state, as it was preburial. Furthermore, conservation processes may alter both the appearance and the composition of wood, which can render the wood unsuitable for certain, forms of analysis.During excavation in a wet site a basic requirement is maintaining high moisture content on site for long periods of time, which can be difficult and exposure to open air will cause damage to surface features, affect the wood structure and make handling difficult. Wholly enclosed shelters with high humidity and moderate temperatures are one of the better environments for working on waterlogged structural wood unless natural conditions are deemed suitable because of dampness and coolness. Judicious use of water sprays and thin polythene sheeting may help delay the decay of wet wood.As far as preservation strategy of wood in situ is concerned, several major requirements must be taken into account, such as the maintenance of an appropriate range of temperature and humidity, the physical protection of the structure, whether buried or exposed, the character of the surrounding or supporting matrix of soil, the stability of the deposits and their permeability, the consistent monitoring of conditions and the ability to amend and adjust as conditions determine over a long time. Little experience has so far achieved in these perspectives, therefore a uniform policy of adequate documentation of the evidence and analytical work should be developed before consigning any important structural wood to a preservation in situ policy.
Νεολιθική εποχή, Καστοριά