Exploring the relationships between Electron Spin Resonance (ESR)/Luminescence (OSL/TL) properties and trace element composition from quartz in various bedrocks (Strengbach catchment, Vosges)

Abstract

International audienceQuartz Thermoluminescence (TL), Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) offer valuable quantitative tools both for understanding sediment provenance and surface processes. However, the variability of quartz sensitivity remains an issue, attributed either to the intrinsic properties of source bedrock, to processes during sediment transport and deposition, or to both. This study addresses these questions by investigating quartz from magmatic, metamorphic, and sedimentary formations in the Strengbach catchment (Vosges Massif, France). Using a combination of ESR, TL, OSL, and LA-ICPMS (Laser-Ablation Inductively Coupled Plasma Mass Spectrometry) trace element analyses, our study reveals significant relationships between quartz TL-OSL/ESR sensitivities and source bedrock characteristics, such as lithology, crystallization conditions, and deformation histories. ESR Ti-centre and TL-OSL signals are notably influenced by trace elements like Al, Li, and Ti. Quartz that underwent high pressure during metamorphism along with those located in the tectonic shear zone show both lowest TL-OSL and ESR intensities, while higher sensitivities are observed in quartz from plutonic rocks and sandstones. This suggests that (i) pressure can be one of the prevailing factors driving changes in quartz TL-OSL/ESR sensitivities (ii) enhanced quartz TL-OSL sensitivity in mature and recycled sediments (sandstones) highlight the importance of sedimentary transport and reworking on TL-OSL and ESR signals.Our results highlight the need for careful interpretation of ESR and TL-OSL signals, both for dating or sourcing, particularly in sediments derived from metamorphic terrains.</p