Abstract: The application of thermal (TL) and optical (OSL) stimulated luminescence on pottery and building materials has allowed to resolve numer-ous problems in both the fields of retrospective do-simetry and dating.Routine measurements request the registration of TL signals obtained on polymineral fine-grained frac-tion (FG) extracted from pottery sherds and bricks used as building material with the Added Dose (AD) technique.One of the reasons of the dispersion of the lumi-nescence measurements when using this fraction is the variability of relative contents of quartz and feld-spars, which due to their differing behaviour influ-encing the equivalent dose (ED) and therefore its uncertainties.The objective of the present work is the solution of this type of problem using the double Single Ali-quot Regeneration (d-SAR) protocol which is widely used to date geological sediments. This allows the ED determination from the quartz-dominated OSL signals obtained from polymineral fraction.Materials and methods: Using bricks taken from a building which is the objet of a specific dating pro-gram, we measured some samples prepared and measured with different techniques in order to deter-mine which technique allows as to obtain date with minimum dispersion.The samples were prepared with FG (4-11 micron) technique and measured with standard AD to obtain TL signals and with d-SAR to register OSL signals. This last methodology requested some adaptation because samples from building materials have low signals and therefore natural doses.The data obtained was compared with those re-corded using OSL emissions of quartz extracted us-ing inclusion technique, QI, (90-150 micron), measured with “classical” SAR protocol.Results: The results from different fractions ex-tracted from bricks using specially adapted FG-OSL-d-SAR methodology, where compared with those obtained by FG-TL-AD and QI-OSL-SAR standard protocols. This comparison showed the prospective for the new approach especially in the chronological determination of historical buildings.
|Stato di pubblicazione||Published - 2010|