黄土细颗粒单测片再生法光释光测年的进展  

Progress in luminescence dating of Chinese loess by Single-aliquot Regenerative-dose (SAR) protocol

作　　者：王旭龙[1] 卢演俦[1] 李晓妮[1] 

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

出　　处：《核技术》2005年第5期383-387,共5页Nuclear Techniques

基　　金：国家自然科学基金项目(No.90102017)资助

摘　　要：报道了黄土细颗粒石英与混合矿物单测片再生法测年中的若干进展。在黄土细颗粒释光测年前处理方面,利用氟硅酸溶蚀法提取可供释光测年的细颗粒石英,突出溶蚀过程需用超声波克服细颗粒矿物表面能的重要性;在此基础上,利用单测片再生法测定洛川黄土细颗粒石英光释光等效剂量,作为标准评估混合矿物红外-蓝光联合激发单测片再生测定等效剂量的可靠性。通过线性激发技术证实了长时间红外激发后蓝光释光信号和细颗粒石英光释光信号中快速和中速信号组份之间存在着相似的特征,提出红外后蓝光释光测年需进行红外激发时间与红外后蓝光释光等效剂量坪实验,以获得蓝光激发前红外激发参数。通过与细颗粒石英等效剂量的对比,系统地研究了细颗粒混合矿物单测片再生法确定的红外与红外后蓝光释光等效剂量的可靠性。Here we reported the improvements in luminescence dating from fine grains of Chinese loess. For isolating fine quartz from polymineral grains in Chinese loess, it is more valuable to use ultrasonic bathing during etching the feldspar by H2SiF6, because of the aggregates of fine grains. IR detection confirmed the purity of OSL signals from fine quartz for luminescence dating purposes. Single-aliquot regenerative-dose (SAR) protocol was used to determine the equivalent dose (DE) for fine quartz OSL, polymineral IRSL and Post-IR OSL in Chinese loess during the last glacial-interglacial. Linear modulation technique was used to identify the characteristic of Post-IR OSL from polymineral grains. It is confirmed that characteristic of Post-IR OSL after long time of IR stimulation is similar to those of fine quartz OSL. In order to obtain reliable DE value from Post-IR OSL of polymineral grains, it is necessary to determine a sufficient IR stimulation time by the plateau test of Post-IR OSL DE v.s. IR stimulation duration, as did for preheating condition in previous luminescence dating. The performance of IRSL and Post-IR OSL in determining the DE value with ranges of 0-300 Gy was also discussed by comparing to fine quartz OSL DE.

关 键 词：细颗粒黄土 红外释光 红外后蓝光释光 单测片技术 

分 类 号：P597[天文地球—地球化学]