黄土细颗粒石英光释光测年中预热温度选取的简易方法  

A SIMPLE APPROACH FOR PREHEAT TEMPERATURE DETERMINATION IN FINE-GRAINED QUARTZ OPTICALLY STIMULATED LUMINESCENCE DATING

作　　者：康树刚[1,3] 卢演俦[1,2] 王旭龙[1] 杜金花[1,3] 

机构地区：[1]中国科学院地球环境研究所,黄土与第四纪地质国家重点实验室,西安710075 [2]中国地震局地质研究所,地震动力学国家重点实验室,北京100029 [3]中国科学院研究生院,北京100049

出　　处：《地震地质》2009年第3期544-550,共7页Seismology and Geology

基　　金：中国科学院黄土与第四纪地质国家重点实验室开放基金(SKLLQG0717);自主部署课题(ZYSQ0807)资助

摘　　要：等效剂量预热温度坪实验是光释光(OSL)测年中确定预热温度的常用手段,一般选择坪区温度作为OSL测年的预热温度。对于黄土细颗粒石英,无论采用单片再生法(SAR)还是简单多片再生法(SMAR),以10s为预热时间,其天然和再生剂量预热温度坪区间均为250～280℃,试验剂量的预热温度分布较广,如180～260℃。常规等效剂量预热温度坪实验需要耗费较长的实验室时间。通过对SMAR法测试数据的再分析发现,天然与再生剂量OSL信号校正强度的比值(N/R)随预热温度的变化与常规等效剂量坪实验中等效剂量随预热温度的变化有着相似的趋势,这样,N/R预热温度坪就可作为黄土样品细颗粒石英等效剂量预热温度坪的替代,为实验室OSL测年确定预热温度提供一个简捷途径。Equivalent dose（De）preheat plateau test is an often used approach to determine an appropriate preheat temperature in optically stimulated luminescence（OSL）dating. The preheat temperature chosen in OSL dating should be in the plateau region. When the preheat time is fixed as 10s,the De preheat plateau regions are 250- 280℃ and 180 - 260℃for regeneration dose and test dose respectively for fine-grained quartz in Chinese loess, no matter using single-aliquot regenerative-dose （SAR） protocol or sensitivity change corrected multiple-aliquot regenerative-close （SMAR）protocol. After reanalyzing the De preheat plateau data derived by SMAR protocol,variation of the ratio of natural OSL intensity to regenerated dose aliquot OSL intensity （N/R）with preheat temperature changes in the similar way with the plot of De as a function of preheat temperature. We suggest that plot of N/R as a function of preheat temperature can be the substitute of De preheat plateau test. This gives us a simple and time-saving approach to determine the preheat temperature in fine-grained quartz OSL dating.

关 键 词：细颗粒石英 单片法 简单多片法 预热温度坪 

分 类 号：P597.3[天文地球—地球化学]