Affiliation: | aDepartment of Geography, University of Liverpool, Liverpool L69 7ZT, UK bInstitut des Sciences de l’Evolution (UMR CNRS–UM2 5554), Université Montpellier II, case 61, pl. E. Bataillon, 34095 Montpellier cedex 5, France cLaboratoire de Géographie Physique (UMR CNRS 8591), CNRS, 1, pl. Aristide Briand, 92195 Meudon, France |
Abstract: | Six samples were collected from a section of Peoria Loess in Eustis, North America, for optically stimulated luminescence (OSL) dating of quartz, and all except one (LV90) produced narrow dose distributions. A comparative study was conducted on this sample and on a ‘well-behaved’ sample (LV91), involving other dating methods and examination of the quartz OSL. These investigations revealed differences in the quartz OSL growth with dose, OSL response to thermal treatments and the range of components within the OSL signals. An ultra-fast component was found in LV90 that displayed a higher rate of sensitivity change than the fast component and this had a malign influence on the determination of the equivalent dose. The distinctive luminescence characteristics of LV90 imply either a change in wind dynamics and/or the source area for the silt. |