宇宙成因核素10Be的地球化学行为及其在黄土示踪研究中的应用

¹⁰Be是一种典型的长寿命宇宙成因核素，对其在自然界中的分布规律、迁移形式和赋存状态等地球化学行为特征的研究，是利用沉积物¹⁰Be记录进行定年和环境示踪研究的理论基础。其中明确¹⁰Be在不同沉积物中的赋存状态是研究¹⁰Be保存性的基础，而¹⁰Be在固相和液相介质中的分配系数Kd则主要反映了¹⁰Be在固相和液相中的迁移能力，对研究自然界不同沉积物中¹⁰Be的迁移性至关重要，直接影响到沉积物中¹⁰Be环境示踪研究的有效性。本文尝试总结了大气成因¹⁰Be在海洋、河流沉积物和土壤中的赋存状态，分析了¹⁰Be分配系数Kd的分布范围及其主要控制因素。在此基础上以土壤中¹⁰Be的分布特征、迁移规律及影响因素研究为参考实例，对比分析了目前已有对黄土-古土壤序列中¹⁰Be地球化学行为研究取得的主要成果，建议未来应从地球化学机制方面进一步加强对黄土地层序列¹⁰Be分布特征、浓度变化规律及可能影响因素的综合研究，为黄土¹⁰Be示踪研究提供更全面的理论依据。

Studies on the geochemistry behaviors of cosmogenic nuclide 10Be and its applications in loess tracing

The geochemical study of ¹⁰Be, a typical long-lived cosmogenic radioactive nuclide, such as distribution, migration and speciation, is the theoretical basis of ¹⁰Be dating and environment tracing. To determine the chemical states of ¹⁰Be in different sediments is the foundation of the study of ¹⁰Be preservation, and the partition coefficient of ¹⁰Be is essential in the study of mobility of ¹⁰Be in different sediments, which directly affects the validity of ¹⁰Be environmental tracing. In this article, we summarized the study of the chemical states and distribution of the cosmogenic nuclide ¹⁰Be in marine sediments, fluvial sediments and soils. We also analyzed the main factors that affect the ¹⁰Be partition coefficient. On the basis of the above analysis, we introduced the study of the distribution characteristics and the migration laws of ¹⁰Be as well as the controlling factors behind those laws in soil as a concrete example. Compared with that in soil, major achievements of geochemical behavior study of ¹⁰Be in loess-paleosol sequence were also introduced. To provide more comprehensive theoretical support for the study of loess ¹⁰Be tracing, we should improve the research in geochemistry mechanisms of ¹⁰Be distribution characteristics, concentration variation and influencing factors in loess stratigraphic sequence in future work.