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选取俄罗斯南部亚速海地区的Chumbur-Kosa(CK)黄土剖面作为研究对象,系统地分析了剖面中常量地球化学元素质量分数以及它们在风化过程中的迁移变化规律,并通过常量元素的相关比值参数(化学蚀变指数、w(Na)/w(K)和残积系数)对剖面的风化淋溶程度进行了初步分析.结果表明:CK剖面主要物质组成以Si、Fe、Ca为主,三者质量分数平均值的总和达到77.61%,常量元素w(Si)>w(A1)>w(Ca)>w(Fe)>w(K)>w(Mg)>w(Na);相对于上部陆壳的平均值,CK剖面呈现贫Na富Ca的特征;常量地球化学元素氧化物以及参数比值与CK剖面各地层特征有较好的对应关系.S2古土壤层中的常量元素氧化物及参数比值呈现出与其他古土壤层相反的变化,产生这种现象的原因可能是在L2沉积初期,由于降水作用导致土壤湿度增加,使活动性元素向下淋溶,并在S2中发生富集;CK剖面尚处于早期以去Ca、Na为主的初级风化阶段,风化程度弱.亚速海地区黄土化学风化过程主要受气候条件的影响,其中降水因素可能起着更为重要的制约作用.
The Chumbur-Kosa (CK) loess section in the Azov region in southern Russia was selected as the research object to systematically analyze the mass fraction of constant geochemical elements in the profile and their migration and variation during the weathering process. Through the correlation ratios of the major elements (Chemical alteration index, w (Na) / w (K) and residual coefficient) were used to analyze the degree of weathering and leaching in the section. The results show that the main material composition of the section CK is Si, Fe and Ca, The sum of the average mass fraction of the two components reached 77.61%, the total content of the elements w (Si)> w (A1)> w (Ca)> w (Fe)> w (K)> w (Mg)> w The average value of the upper continental crust and the CK profile show the feature of poor Na-rich Ca. The correlation between the constants of elemental oxides and the ratio of parameters is consistent with the stratigraphic features of the CK profile. The contents of major elemental oxides, The ratio of the parameters shows the opposite change from other palaeosol layers. The reason for this may be that in the early stage of L2 deposition, the soil moisture increases due to precipitation, causing the active elements to leach downward and enrichment occurs in S2 ; CK profile is still in the early stage of primary weathering to Ca, Na-based primary weathering, weathering The degree of weakness.The chemical weathering of loess in Azov region is mainly affected by climatic conditions, of which precipitation may play a more important role in the control.