Accurate-parametric SAR-TL dating protocols for older sediments using quartz

Yi Gu; Meng Wang; Qingxian Zhang; Liangquan Ge; Lipeng Xu; Heng Lu

doi:10.1016/j.apradiso.2021.110072

Accurate-parametric SAR-TL dating protocols for older sediments using quartz

Appl Radiat Isot. 2022 Mar:181:110072. doi: 10.1016/j.apradiso.2021.110072. Epub 2021 Dec 24.

Authors

Yi Gu¹, Meng Wang², Qingxian Zhang², Liangquan Ge², Lipeng Xu³, Heng Lu²

Affiliations

¹ Applied Nuclear Techniques in Geosciences Key Laboratory of Sichuan Province, Chengdu University of Technology, Chengdu, 610059, China. Electronic address: guyi10@cdut.edu.cn.
² Applied Nuclear Techniques in Geosciences Key Laboratory of Sichuan Province, Chengdu University of Technology, Chengdu, 610059, China.
³ Sichuan Management & Monitoring Center Station of Radioactive Environment, Chengdu, 610031, China.

PMID: 34968882
DOI: 10.1016/j.apradiso.2021.110072

Abstract

Thermoluminescence (TL) dating is one of the most significant chronological tools used in Quaternary research. However, for changes in the characteristics of quartz, the larger deviation is still a problem in TL dating, especially with the single-aliquot regeneration-does (SAR) procedure. In the SAR-TL protocol, changes in the characteristics of quartz inevitably cause a shift in the TL peak position and a reduction in the sensitivity of the TL peak during repetitive thermal treatment. In this paper, we studied the optimal TL parameters to minimize the effect of the above problems for TL dating. Based on the optimization experiment combining OSL and TL measurements, the optimal preheat temperature was found to be 300 °C for both silt-sized grains and sand-sized grains, which eliminates the remainder of the 325 °C TL signals and inhibits the 375 °C TL peak position shift. Referring to the test does in SAR-OSL dating protocol, the optimal test doses, 200 Gy and 250 Gy for the silt-sized grains and sand-sized grains respectively, were determined to correct the reduction in TL sensitivity, and they were added to improve the SAR-TL protocol. The improved SAR-TL protocol with the optimal measurement parameters, which we called the accurate-parametric SAR-TL protocol, improves the accuracy of quartz TL dating and expands the range of accurate TL dating. For the experimental doses of 400 Gy and 700 Gy, the relative error of D_e obtained by the accurate-parametric SAR-TL protocol was less than ±5.5% for both silt-sized grains and sand-sized grains. In addition, we discussed the application conditions of the accurate-parametric SAR-TL protocol and the method that obtains the same level of thermal lag for different luminescence measurement equipment.

Keywords: Older sediments; Optimal TL parameters; Quartz aliquots of different sizes; SAR-TL dating; Thermal lag.

Publication types

Review