Investigations on the degree of bleaching of quartz OSL signals using modern aeolian dust from western Loess Plateau, China

Geochronometria

Zhongping Lai¹  Tianlai Fan²  Hui Zhao²  Fahu Chen²  Yuxin Fan² 

[1] Chinese Academy of Sciences;Lanzhou University

关键词: Incomplete bleaching;    Quartz;    Modern dust;    Chinese Loess Plateau;   

DOI  :  10.2478/s13386-013-0112-y

学科分类：社会科学、人文和艺术（综合）

来源: Politechnika Slaska * Instytut Fizyki

【 摘 要 】

Optically Stimulated Luminescence signal of quartz extracted from modern aeolian dust with known maximum age (about decades) was analyzed in terms of degree of bleaching. The results of dose recovery tests show that the modified double single-aliquot regenerative-dose protocol with the early background subtraction is robust for dating these modern dusts using small aliquots. Bleaching of these dusts is discussed based on the distribution of De values in histograms, scatter plots of De versus sensitivity corrected natural OSL signal and comparison between measured De and expected De. The results indicate that most dusts were completely bleached but some dusts were not completely bleached. For those incompletely bleached dusts in Lanzhou area, the maximum OSL age overestimation is up to ∼1 ka, which might be caused by fast deposition accompanied by heavy sand/dust storms. The research suggests that cautions should be given to OSL ages younger than 1 ka in the western China close to deserts.

【 授权许可】

Unknown