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Institute of Physics Luminescence dating of
geological and archaeological objects Summary Absolute
dating by luminescence methods is widely applicable in geology,
geomorphology, palaeogeography and archaeology. It allows the
determination of ages of geological sediments and archaeological objects. Description The
dose of natural ionising radiation is preserved in mineral grains, e.g.
quartz grains, which absorb this radiation. These grains, when exposed to
light of selected wavelengths (in case of optically stimulated luminescence -
OSL) or upon heating to 500°C (in case of thermoluminescence -
TL) emit light called luminescence. The amount of emitted luminescence
is a function of the ionising radiation dose absorbed prior to measurement.
Luminescence measurements enable determination of the absorbed dose of
natural radiation. If this is combined with results of measurements of
radioactivity of the sample and its environment then the absolute age of
the sample can be determined. Luminescence methods measure the time since the
last event zeroing the luminescence previously acquired by grains. In case
of the OSL method it the last exposure of grains to light and in the case of
TL it is the last heating to the temperature above 350- For OSL
dating we employ the SAR method - Single Aliqutot Regenerative method.
This method has been shown by many researchers as giving the most accurate
results to date. Advantages Most
geological sediments and archaeological ceramics contain quartz grains and if
only the dated event was associated with exposure to light or to an elevated temperature
then they may be subject to luminescence dating. Luminescence dating is an
absolute method and it provides dates with 5-10% uncertainty depending on the
context and the behaviour of the sample. The accuracy is controlled by
factors like homogeneity of the sediment, degree of moisture, completeness of
bleaching at the time of deposition and others. The
range of the method is from about 100 years to some 500 000 years and may
additionally depend on the radioactivity of the dated object and its surroundings,
as well as on the properties of quartz grains. Offer Dating
of fired materials (ceramics, flints, etc.) by TL or OSL methods. Dating
of geological sediments by OSL methods, mainly single aliquot dating
techniques. The cost of one date is 1700 PLN + VAT (23%)= 2091 PLN (ca. 520 Euro) We are open to suggestions of scientific
collaboration as well as applications for funding for joint projects. In
order to start the dating process we need to receive your order signed by a
person responsible for finances in your institution. The order should be
addressed to the address given below. The order should contain the following
information: your address, VAT number, number of samples, total gross amount
(i.e. number of samples x 1700 x 1.23 PLN), name of the site, data of the
contact person and the latest chargeable date. After that we will prepare a
contract. Once the dating is completed you will receive a dating report. Currently
the waiting time for results is 5-9 months. Address Silesian
University of Technology Contact Dr.
Piotr Moska |