Combined dating methods applied to building archaeology: the contribution of thermoluminescence to the case of the bell tower of St Martin's church, Angers (France)

International audienceSt Martin's church, Angers, is emblematic of the problems raised in pre-12th century history of architecture. In view of the importance of this building, it was necessary to attempt to define its dating and this study particularly focuses on its bell-tower. In addition to the conclusion resulting from the interpretation of written sources and typological criteria positioning the construction of the site at the beginning of the 11th century, not only a significant number of 14C dates were carried out on charcoals from the masonry structures, but also independent dating by archaeomagnetism and thermoluminescence were performed on bricks from the bell-tower. The whole results from these three different methods agree and indicate the lower level of the bell-tower was likely built in the 9th century, disputing evidence to the theory of construction in the 11th century of the church. Presented here are the detailed results obtained from the thermoluminescence (TL) dating analysis