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土壤中的钙质结核可分为软结核、硬结核和钙质硬盘３种形态，其化学组成以ＣａＣＯ３为主，矿质全量组成的各氧化物平均含量水平的顺序为：ＣａＯ＞ＳｉＯ＿２＞Ａｌ＿２Ｏ＿３＞Ｆｅ＿２Ｏ＿３＞ＭｇＯ＞Ｋ＿２Ｏ＞Ｎａ＿２Ｏ＞ＴｉＯ＿２＞ＭｎＯ＞Ｐ＿２Ｏ＿５。但在某些软结核中，ＳｉＯ＿２含量仍大于ＣａＯ含量。微形态分析结果表明，软结核为碳酸盐颗粒的胶结体，常嵌埋较多的土壤基质、石英、长石等粗颗粒；硬结核多为碳酸盐和方解石的胶结体，许多大孔隙为方解石填满成晶管、晶囊状；钙质硬盘主要是碳酸盐凝团及方解石胶结而成的多孔方解石胶结体。３种结核都含有铁锰浸染斑。随着结核发育程度的增加，方解石的结晶程度增加，Ｃａ的浓度增大，电子探针能谱的分析结果也证明了这一点。钙质结核粉晶Ｘ射线衍射分析表明，其主要矿物组成为方解石，含较多石英、长石．少量黑锰矿和水铁矿，很少或不含白云石，这与化学组成、微形态分析、电子探针能谱的结果互为印证。
Calcareous nodules in soil can be divided into three forms: soft nodules, hard nodules and calcium hard disks. The main chemical components are CaCO3, and the order of the average contents of all the oxides is CaO> SiO 2> Al 2 O 3> Fe_2O_3> MgO> K_2O> Na_2O> TiO_2> MnO> P_2O_5. However, in some soft nodules, the SiO 2 content is still greater than the CaO content. Micro-morphological analysis showed that soft nodules were the cement of carbonate particles, and often embedded more soil matrix, quartz, feldspar and other coarse particles; hard nodules were mostly cements of carbonate and calcite, and many macropores Filled with calcite into a crystal, cystic; calcium hard disk is mainly carbonate agglomeration and calcite cemented porous calcite cement. All three kinds of tuberculosis contain iron-manganese stains. With the increase of the degree of tuberculosis, the degree of crystallization of calcite increases, the concentration of Ca increases, and the result of electron probe energy spectrum also proves this. Calcium tuberculosis powder X-ray diffraction analysis showed that the main mineral composition of calcite, containing more quartz, feldspar. A small amount of black manganese ore and iron ore, with little or no dolomite, which is confirmed by chemical composition, micro-morphology analysis, electron probe energy spectrum results.