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通过对甘肃灵台风成黄土－古土壤－红粘土序列中钙质结核的野外分布及形态特征观察，并对主元素和微量元素进行化学分析，发现结核中氧化物活动组分和惰性组分含量的比值在剖面中自下而上逐渐变大，反映了结核形成时其上覆土层所经历的淋溶程度逐渐增强；而ＭｇＯ含量和用ＣａＣＯ_３含量校正后的ＭｇＯ／ＣａＯ比值则逐渐减小，指示结核形成时环境温度逐渐降低。灵台剖面自下而上不同层位结核中Ｓｒ／Ｂａ比值及ＣａＣＯ_３含量的变化同氧化物含量及比值变化具有类似的特征，暗示了黄土高原自晚第三纪到第四纪间冰期的气候总体有向冷湿方向演化的趋势。其中红粘土堆积中钙质结核Ｓｒ／Ｂａ比值的大幅变化，说明结核的形成既有强烈淋溶成因，又有地下水强烈蒸发作用的参与，暗示了在晚第三纪，黄土高原可能有以强降水和强蒸发为组合的湿热气候波动特征。
Through the observation of the distribution and morphological characteristics of calcareous nodules in the loess-paleosol-red clay series from Lingtai, Gansu Province, and analyzing the chemical elements of the main elements and trace elements, it was found that the active and inactive components The ratio of MgO content and MgO / CaO content corrected by CaCO_3 gradually decreased, and the ratio of MgO to CaO_3 decreased gradually, Indicate the gradual decrease of ambient temperature when tuberculosis is formed. The variation of Sr / Ba ratio and CaCO 3 content in bottom-up tuberculosis of Lingtai section is similar to that of oxide content and ratio, suggesting that the climate of the ice sheet from the Late Tertiary to Quaternary in the Loess Plateau There is a trend toward the direction of cold and wet. Among them, the sharp change of Sr / Ba ratio of calcareous nodules in the accumulation of red clay indicates that the formation of nodules is caused by the strong leaching and the strong evaporation of groundwater, suggesting that in the late Tertiary, the Loess Plateau might have strong Precipitation and strong evaporation are combined wet and hot climate fluctuations.