摘要
宇宙成因核素21Ne测年方法在地表暴露测年方面具有测年范围宽、定年材料选择范围广、测试所需样品量少、前处理过程简单等优点,是第四纪年代学领域中一种重要的测年方法然而,由于受到稀有气体质谱仪分辨能力的制约,21Ne测年方法在国内的应用尚处于起步阶段.本文在对质谱仪纯化系统加装超低温冷泵的基础上,初步建立了宇宙成因核素21Ne测年方法的测试流程,并分别测试了标准样CREU-1的Ne同位素含量和龙首山阶地的21Ne年龄检验了该测试流程在石英样品暴露定年方面的可行性.该测试流程的建立,将为宇宙成因核素21Ne测年方法在第四纪地质、活动构造等研究领域的应用提供重要技术支撑.
The stable cosmogenic isotope 21 Ne provides an extremely powerful tool for surface exposure dating, because of its extremely wide exposure dating range, requirement for comparatively small samples（about 0.2–1.0 g）, and relatively simple sample preparation process. Furthermore, in addition to quartz, 21 Ne analysis is applicable to many other types of silicate, such as pyroxene, olivine, and biotite. Cosmogenic 21 Ne has become a significant geochronological technique in Quaternary geology; however, because of the high resolution required to separate the 40Ar2＋ peak from that of 20Ne＋ in mass spectrometry, the development of the cosmogenic 21 Ne exposure dating technique in China is still in its early stages. A measurement procedure has been established in our laboratory for cosmogenic 21 Ne dating based on improvement of the purification system of the mass spectrometer by adding a cryogenic pump. A highly enriched 21 Ne standard material（CREU-1） and an alluvial fan surface sample from Longshou Shan, Inner Mongolia, China, were analyzed, and the data from these two samples have demonstrated the feasibility of our 21 Ne analytical procedure for quartz. The establishment of this neon analytical procedure provides a promising tool for the development of a cosmogenic 21 Ne dating method for use in many fields, such as Quaternary geology and active tectonics.
出处
《科学通报》
EI
CAS
CSCD
北大核心
2014年第27期2707-2713,共7页
Chinese Science Bulletin
基金
中国地震局地质研究所基本科研业务专项(IGCEA1126)
国家自然科学基金(41202132)资助
