蒋家沟流域古泥石流物质选频释光特征研究  

Characteristic of Selected Frequency Luminescence for Paleo-Debris Flow Deposits in Jiangjia Valley

作　　者：刘兆文[1] 魏明建[1] 潘宝林[1] 刘超[1] 李东旭[1] 

机构地区：[1]首都师范大学光断代实验室,北京100048

出　　处：《原子能科学技术》2008年第B09期362-366,共5页Atomic Energy Science and Technology

基　　金：北京市教委科技计划基金重点资助项目(KZ200810028015);中国科学院山地灾害与地表过程重点实验室开放基金联合资助项目

摘　　要：采用BG2003释光仪研究云南蒋家沟流域泥得坪台地、多照台地、大凹子沟、蒋家沟4个地点的8个古泥石流物质样品的选频释光特征,确定了发射光子的特征发射频率。在蓝光(488 nm)激发下,各样品的发射光子分别出现在波长为300、310、320、400、460 nm处。用绿光(532 nm)激发上述相同样品,发现其在波长为300、310、320、460 nm时的计数最为明显。进而确定出泥得坪堆积台地在不同时期泥石流物质释光谱图大体一致,但大凹子沟与多照古泥石流堆积台地不同时期的泥石流物质释光谱图表现出差异。以泥得坪堆积台地为例,该台地的上部、中上部、下部泥石流物质样品在绿光激发下,在波长为310、3204、60 nm处,随辐照剂量的加大,样品的释光光子数递增。由这一规律可确定泥得坪堆积台地泥石流物质用于年龄测定的波长。Eight paleo-debris flow samples from Nideping, Duozhao, Dawazi valley, and Jiangjia valley in Yunnan Province were tested with BG2003 luminescence spectrograph. The characteristic spectra of the selected frequency luminescence of paleo-debris flow deposits from the different locations were obtained. Excited at 488 nm, the wavelengths of emission photons from all samples are 300, 310, 320, 400 and 460 nm. With green excitation （532 nm）, the wavelengths of emission photons from all samples are 300, 310, 320 and 460 nm. Then it is determined that the luminescence spectrographs of Nideping are almost same in different time, however, they are different in Dawazi valley and Duozhao. Taking Nideping for example, excited at green, the debris flow substances from the upper, middle, or lower zone of this platform. Responsed to increasing irradiational dose at 310, 320, and 460 nm, we can define the wavelengths used for dating.

关 键 词：蒋家沟流域 古泥石流 选频释光 

分 类 号：O482.3[理学—固体物理]