Environmental stability of organic material in archaeological sites

Full text: A series of analytical techniques have been used to evaluate the degree of diagenesis and interaction with the surrounding environment, of different types of organic material collected from archaeological sites (wood, charcoal, twigs, leaves, humic material etc.). These processes are mostly initiated by the generation of free radicals within oxygen -containing functional groups of the biopolymers forming the structure of these organic materials. These free radicals become active sites for incorporation of low molecular weight mobile organic compounds or carbon dioxide into the structure of the biopolymer. In many cases, the degree of exchange with the surrounding sedimentary matrix has not been enough to affect the 14C ages of relatively young material (< 10 k years BP). Problems could occur with 14C ages of older material