Mineralogy of Manganese Oxide Minerals in Iron Manganese Nodules of Several Main Soils in China

摘要

X-ray diffraction and selective chemical dissolution methods were used to investigate the composition of rnMn oxide minerals in Fe-Mn nodules of several main types of soils in China. The changes of relative intensity rnof X-ray diffraction patterns were studied both before and after chemically selective dissolution. It was found rnthat lithiophorite was a common Mn oxide in all examined Fe-Mn nodules. Todorokite, however, was a rnpredominant Mn oxide in Fe-Mn nodules in cal-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn rnnodules of arp-udic Luvisols in Wuhan and Zaoyang, Hubei Province, contained birnessite and vernadite.rnHollandite was found in Fe-Mn nodules of alt-udic Ferrisols of Yizhang, Hunan Province; arp-udic Luvisols rnof Zaoyang, Hubei Province; and cal-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn nodules in rnalt-udic Ferrisols of Guiyang, Hunan Province, had a few coronadites. Mineralogy of Mn oxide minerals in rnsoil Fe-Mn nodules was related to soil environment, soil types and quantities of relevant cations.