부산대학교 도서관

Here, we provide the first report on the ages of 54 archaeological levels in 38 caves in northern Spain by means of the aspartic acidd/l ratio measurements in Patella shells, with good results. For this purpose, we developed an age calculation algorithm that allows the numerical dating of deposits from other archaeological localities in the area and nearby regions. We conclude that the sample size—that is, the number of shells analysed within a single level—reinforces the importance of analysing numerous specimens per horizon and the understanding of the time-averaging concept. The ultrastructure of different species of Patella shells was also studied, showing calcite in their apexes and aragonite at their margins. [ABSTRACT FROM AUTHOR]