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本文研究了钙质变性土中铁锰结核的矿质全量组成、微量元素丰度、微形态特征以及土壤和铁锰结核中各形态铁锰氧化物的组成特点。结果表明，铁锰结核中仍以ＳｉＯ２含量最高，但Ｆｅ２Ｏ３含量增加超过了Ａｌ２Ｏ３，ＭｎＯ含量大大增加超过了Ｋ２Ｏ、Ｎａ２Ｏ、ＴｉＯ２和ＭｇＯ的含量。所测定的９种微量元素中以Ｂａ含量最高，其次是Ｖ、Ｎｉ、Ｃｏ３种铁族元素，Ｃｕ和Ｐｂ含量也较高，但Ｚｎ和Ｃｒ含量较低。一般黑土层中的结核较小，颜色较深，薄片观察可见粗骨颗粒表面有亮线状光性定向粘粒，凝团、结核外部均有光性定向粘粒与铁共聚现象，含方解石较少。砂姜层中的铁锰结核大多是铁质方解石混合凝团或复合凝团，含较多碳酸盐及方解石，凝团表面仍可见光性定向粘粒与铁共聚呈同心圆垒结。铁锰结核中的氧化铁主要是游离铁，铁游离度达７８％，晶化度达８２．２％，远高于土壤中的铁氧化物。氧化锰的游离度在９０％以上，高于铁游离度。锰的活化度多在３０％以上，明显高于铁的活化度，并且不同层次中的铁锰结核，其锰的游离度和活化度没有明显差异，说明锰在土壤中比铁更加活跃。
In this paper, the mineral composition, trace element abundance, micro-morphological characteristics of Fe-Mn nodules in calcareous denudation soil and the compositional characteristics of various forms of Fe-Mn oxides in soils and Fe-Mn nodules were studied. The results show that the content of SiO2 is still the highest in Fe-Mn nodules, but the content of Fe2O3 exceeds that of Al2O3, and the content of MnO greatly exceeds the content of K2O, Na2O, TiO2 and MgO. Among the nine trace elements, the content of Ba is the highest, the content of Fe, Ni and Co are the second, and the content of Cu and Pb are higher, but the contents of Zn and Cr are lower. In common black soil layer, the tubercle is smaller and darker in color. The observation of thin slices shows that there are bright linear optical directional clay particles on the surface of coarse bone particles. less. Most of the iron-manganese nodules in the layer of sand ginger are iron-based calcite mixed complex or complex agglomerates containing more carbonates and calcite. Ferric iron in nodules is mainly free iron with an iron freeness of 78% and a crystallinity of 82.2%, much higher than iron oxides in the soil. Manganese oxide freeness in more than 90%, higher than iron freeness. The activation degree of manganese is more than 30%, which is obviously higher than the activation degree of iron. And there is no obvious difference in the freeness and activation degree of manganese in different levels of iron-manganese nodules, which indicates that manganese is more active than iron in the soil.