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Figure 13An SEM of class III condition of waterlogged archaeological oak. Note the
well-preserved cell wall layers
inclusion. Sea salt is passively introduced in marine environments, iron(III) is
actively chelated by cellulose and tannates, and high concentrations of iron
corrosion products build up as a consequence. As the wood becomes anoxic,
sulfate-reducing bacteria (SRB) convert these salts to metal sulfides. A phys-
ical consequence of mineral inclusion is that the pores between the lumina
are blocked, and the wood becomes impermeable.
3.3 Storage of Waterlogged Archaeological Wood
In comparison to aerobic environments, deterioration of archaeological wood
in the anoxic sediments of the seabed occurs at a slow rate. Buried waterlogged
archaeological wood will suffer little deterioration, for as long as the anaerobic
environment remains undisturbed. When removed from its burial environ-
ment, physical,chemical and biological degradation ensues and the wooden
artefact must be recovered and stored or conserved soon after exposure. The
waterlogged state of archaeological wood must be maintained on its removal
from the marine environment until it is conserved.
The fundamental problem encountered if waterlogged archaeological wood
is allowed to dry in an uncontrolled manner, is that it may shrink, collapse,
distort, split and even in severe cases, completely disintegrate. The situation
becomes a particular problem if the recently recovered wood is stored under
conditions that do not prevent further deterioration. In an ideal world, it is