Optically Stimulated Luminescence Sensitivity of Quartz for Provenance Analysis

Autor(es)

Sawakuchi, Andre Oliveira ; Goncalves Rodrigues, Fernanda Costa ; Mineli, Thays Desiree ; Mendes, Vinicius Ribau ; Melo, Dayane Batista ; Chiessi, Cristiano Mazur ; Fonseca Giannini, Paulo Cesar

• Tipo de documento: Artigo Científico
• Fonte: METHODS AND PROTOCOLS; v. 3, n. 1, p. 13-pg., 2020-03-01.

Resumo

Finding the source or provenance of quartz grains occurring in a specific location allows us to constrain their transport pathway, which is crucial information to solve diverse problems in geosciences and related fields. The optically stimulated luminescence (OSL) sensitivity (light intensity per unit mass per unit radiation dose) has a high capacity for discrimination of quartz sediment grains and represents a promising technique for provenance analysis. In this study, we tested the use of quartz OSL sensitivity (ultraviolet emission) measured under different preheating temperatures and with blue light stimulation at room temperature (similar to 20 degrees C) for sediment provenance analysis. Quartz OSL sensitivity measured at 20 degrees C is positively correlated with the sensitivity of an OSL signal measured using procedures (preheat at 190 degrees C for 10 s, blue stimulation at 125 degrees C and initial 1 s of light emission) to increase the contribution of the fast OSL component, which has been successfully applied for sediment provenance analysis. The higher OSL signal intensity measured without preheating and with light stimulation at room temperature allows the use of lower given doses, thus reducing measurement time. Additionally, the OSL sensitivity measured at 20 degrees C in polymineral silt samples of a marine sediment core is also suitable for provenance analysis, as demonstrated by comparison with other independent proxies. OSL signals obtained through light stimulation at room temperature have thus the potential to considerably expand measurement possibilities, including in situ measurements using portable OSL readers. (AU)

• Processo FAPESP: 18/12472-8 - Origem e cronologia de substratos arenosos na Amazônia: implicações para evolução quaternária dos ecossistemas de vegetação aberta
• Beneficiário: Fernanda Costa Gonçalves Rodrigues
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/21942-4 - Registro sedimentar quaternário na bacia do rio Parnaíba, Piauí: um estudo multi-indicadores voltado à investigação de mudanças climáticas
• Beneficiário: Vinícius Ribau Mendes
• Modalidade de apoio: Bolsas no Brasil - Doutorado