黄河流域现代沉积物的石英光释光残余剂量特征  

Residual dose of quartz Optically Stimulated Luminescence signals in modern sediments of the Yellow River Basin

作　　者：刘霞 刘剑刚[1] 安萍[2] 安琪[3] 王昌盛 吕荫 徐德华 于禄鹏 Xia Liu;Jiangang Liu;Ping An;Qi An;Changsheng Wang;Yin Lv;Dehua Xu;Lupeng Yu(Luminescence Research Laboratory,School of Geography,Liaoning Normal University,Dalian 116029,Liaoning,China;Luminescence Research Laboratory,College of Resources and Environment,Linyi University,Linyi 276000,Shandong,China;Qinghai Institute of Hydrogeology,Engineering Geology and Environmental Geology,Xining 810000,China;School of Geography Science,Taiyuan Normal University,Jinzhong 030619,Shanxi,China)

机构地区：[1]辽宁师范大学地理科学学院光释光实验室,辽宁大连116029 [2]临沂大学资源环境学院释光年代学实验室,山东临沂276000 [3]青海省水文地质工程地质环境地质调查院,青海西宁810000 [4]太原师范学院地理科学学院,山西晋中030619

出　　处：《中国沙漠》2024年第6期26-36,共11页Journal of Desert Research

基　　金：国家自然科学基金项目(41761144073,42371020);山东省高等学校“青创人才引育计划”建设团队项目(鲁教科函2021-51)。

摘　　要：现代河流沉积物的光释光残余剂量对于准确测定其光释光年代以及认识河流地貌演化及侵蚀-沉积过程具有重要意义。黄河泥沙来源广、沉积过程复杂,为系统了解黄河全流域现代沉积物释光残余剂量的基本特征,对黄河流域多个河段、多种粒径的现代沉积物进行了石英光释光等效剂量测试。结果表明:不同粒径石英的残余剂量存在明显差异。粗颗粒石英整体晒退较好(平均5.0 Gy),细颗粒石英的晒退最差(平均14.6 Gy),最大残余剂量可达52.8 Gy(约相当于20 ka)。不同粒径石英的晒退情况存在区域差异,黄河源区和潼关-花园口段的粗颗粒石英(1.5~6.9 Gy)比中颗粒(2.6~23.9 Gy)残余剂量小;而兰州-晋陕峡谷段(0.4~1.0 Gy)和济南-黄河口段(~1.2 Gy)的中颗粒石英残余剂量则最小。黄河下游河段不同粒径的残余剂量呈现随搬运距离增加而减少的趋势。这些结果表明黄河流域现代沉积物的残余剂量可能受物源供应、搬运方式和搬运距离的控制,其复杂的机制反映了针对具体河段和测试粒径进行残余剂量分析的必要性。The Optically Stimulated Luminescence(OSL)dating of modern fluvial sediments is important for building of accurate luminescence chronology and understanding fluvial geomorphological evolution and erosion-deposition processes.The complex sediment sources and deposition processes of the Yellow River highlight the systematic understanding of the modern OSL residual doses throughout the entire river basin.Here,equivalent doses of modern quartz of different grain sizes and from different reaches of the Yellow River were measured.The results showed distinct residual doses among different grain sizes of quartz.Coarse-grained quartz exhibited most sufficient bleaching(average 5.0 Gy),while fine-grained quartz showed the poorest bleaching(average 14.6 Gy),with a maximum residual dose of 52.8 Gy(approximately equivalent to 20 ka).Moreover,regional variations were observed in the bleaching levels of quartz of different grain sizes.In the source region of the Yellow River and Tongguan-Huayuankou reaches,the residual doses of coarse-grained quartz(1.5-6.9 Gy)were smaller than that of medium-grained quartz(2.6-23.9 Gy).However,the residual doses of medium-grained quartz in reaches between the Lanzhou to Jin-Shaan Gorge reach(0.4-1.0 Gy)and Jinan to Yellow River Estuary(about 1.2 Gy)were smaller.Furthermore,the residual doses of different grain sizes tended to decrease with increasing transport distance in the lower reaches of the Yellow River.These results indicate that the residual doses of modern sediments in the Yellow River Basin may be controlled by factors such as sediment source,transport mode,and transport distance.Such complex mechanisms highlight the necessity of residual dose analyses for specific river reaches and grain-size fractions.

关 键 词：现代沉积物 残余剂量 石英 释光测年 黄河 

分 类 号：P533[天文地球—古生物学与地层学]