Chronology is the temporal
basis of the landscape in motion, as it expresses changes in a diachronic
sense. The chronological relations between two, ideally, subsequent phases of
human history are what is referred to as relative chronology. It presumes the
superposition of two features or layers and allows for the relative dating of
these features or of the archaeological material found in them. Main problems
of this type of dating are the possibility of a hiatus in the sequences, i.e.
not all phases of past human activities are present in the superposition, or
that the formation of the features and the deposition of the materials in the
features or layers is not representative for a short period, e.g. a burial, but
rather for a longer process, e.g. filling in of an abandoned pit-house. The shorter
the time span, between the creation of the feature and the deposition of the
archaeological material within the feature or layer, the more accurate the
dating will be. It is clear after this reasoning that burials are ideal
candidates for an accurate, short-time span, dating, but sadly enough very few
instances have such superposition. In this case, it means that information in
regards to these, superposition, must be inferred to from other stratigraphic
contexts, e.g. multi-layered settlements. Since the source of the relative
dating is somewhat eclectic it is obvious that smaller discrepancies would
appear in the general view of chronology, and that several chronological
systems exist.
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| Relative chronology of the Late Copper Age and Bronze Age in the Eastern Carpathian Basin, circ. third and second millenniums BCE ©Tibor-Tamás Daróczi
The absolute chronology is
the method of dating which utilises techniques of natural sciences, e.g. C14,
termoluminescens, archaeomagnetism, in order to establish the age of an artefact in years, i.e. numbers, in a
probabilistic senses. Most commonly used method within archaeology is the C14
dating, which consists of the measuring of the remaining amount of a decaying C14
isotopes. This decay happens naturally and it is referred to as a beta decay,
which in the presented case turns the C14 isotope through emissions
of electrons or positrons into and N14 stable isotope. It is applied
to all formerly living creatures, as this decaying process only starts after
the metabolism has stopped. Since the fluctuating variables in the environment
the decay process is not uniform, it needs an adjustment called calibration.
This is done by means of dendrochronology, through which from environmental
data acquired from plants, e.g. tree rings, and the decaying rate of C14
can be inferred to on yearly basis.
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