实验室概况

释光测年实验室成立于2023年，配备有Risø TL/OSL Reader DA-20释光测年仪，主要对沉积物中的石英和长石颗粒进行定年。实验室致力为国内外地质学家、地貌学家、考古学者提供一个高水平的测年实验室，在第四纪年代学、地貌学、环境考古和全球变化等领域的研究中发挥重要作用，提升我国第四纪年代学研究的国际学术竞争力。实验室对国内外研究人员高质开放。

仪器设备

所拥有的Risø TL/OSL Reader DA-20释光测年仪，集成了真空传感系统、单光子计数放大器/鉴别系统、近红外、蓝光和绿光LED激发光源系统，可准确测得石英和长石矿物中储存的光子，从而获得可靠的年代。该仪器具有适用范围广、分辨率高、数据质量高的突出优越性，除了能获得火山沉积物年代外，该仪器还广泛用于风成沉积物、湖相沉积物、河流相沉积物等第四纪时期的各类沉积物中。除传统的单片测量外，释光测年仪配有的单颗粒装置使得对单个颗粒进行年代测量成为可能。该装置可以通过对几百至几千个颗粒进行逐一测量，并分析其结果分布，区分出埋藏前信号被完全清空的颗粒，使得释光可以应用于复杂的沉积环境。

测试项目

本实验室主要进行如下方面的分析测试工作：

(1) 石英、长石单片定年

(2) 石英、长石单颗粒定年

测试方法

单片再生法

自然界的沉积物中均含有微量铀、钍、钾等放射性元素，这些元素在衰变过程中会释放α、β、γ 射线而使石英、长石等矿物晶体电离，产生游离电子。 一些游离电子被晶格缺陷陷获后贮藏在陷阱中，为陷获电子。当石英、长石等矿物受到热或者光照时， 陷获电子可获得能量，逃出陷阱，并在此过程中出现发光现象。光释光测年方法就是通过光束激发使晶体中储存的电离辐射能释放出来。本实验室将在暗室中提取沉积物的石英或长石颗粒，并对其等效剂量进行测量，测量方式为单片再生法。如果样品埋藏环境复杂，可选择单颗粒法进行测年，即通过对几百至几千个颗粒进行逐一测量，并分析其结果分布，选择合适的数值分析方法，从而获得可靠年代结果。

引用格式中英文：

Sample preparation was conducted under subdued red-light conditions. About 2 cm from both ends of the sampling tubes and the outer surface (~1 cm) of the sample blocks were removed, as they may potentially have been exposed to sunlight during sampling, and were used for determining environmental dose rates. The interior samples were used to isolate quartz and potassium-rich feldspar (K-feldspar) grains for De determination. The samples were treated with hydrochloric acid (HCl) and hydrogen peroxide (H2O2) to remove carbonates and organic material, respectively. The 180–212-mm diameter grain size fraction was separated by wet sieving. Density separation with sodium polytungstate solutions was used to isolate quartz and K-feldspar. The quartz and Kfeldspar fractions were then etched in 40 and 10% hydrofluoric acid (HF) acid, respectively, for 40 min to remove the alpha-irradiated outer layer and remove any feldspar grains from the quartz fraction. After HF etching, they were rinsed with 10% HCl to remove any fluorides formed during HF etching. Finally, these grains were dried and re-sieved to recover grains in selected size fractions.

测试方法相关文章：

Xue Rui, Bo Li, Yujie Guo, 2020. Testing the upper limit of luminescence dating based on standardized growth curves for MET-pIRIR signals of K-feldspar grains from northern China. Quaternary Geochronology 57, 1-11.

实验室位置

吉林省长春市朝阳区西民主大街938号 吉林大学朝阳校区油页岩综合楼143室