泥河铁矿床位于庐枞火山岩盆地西北部边缘，紧邻郯庐断裂带，南西距罗河铁矿仅3千米，为一大型含硫磁铁矿、大型硫铁矿、中型硬石膏矿组成的多矿种隐伏矿床。 磁铁矿体分布于矿床的南西部，呈透镜状或似层状产于侵位于早白垩统砖桥组的辉石闪长玢岩岩侵穹窿的顶部；硫铁矿体分布于矿床的北东部，主要有两个产出部位，一是产于辉石闪长玢岩体内，与铁矿体共生；二是产于砖桥组下段火山岩中，与层位有关；硬石膏矿体分布在矿床中部，呈透镜状产于砖桥组下段火山碎屑岩中。矿石类型复杂，磁铁矿划分了8个自然类型，硫铁矿划分了5个自然类型。矿物种类多达40余种，铁矿石本身为高硫、高磷矿石，有用组分除铁、硫、硬石膏外，磁铁矿和硫铁矿矿石中还伴生有磷、钒、钛、钴、铜、锌等有益有害组分。 矿床围岩蚀变强烈，分布范围广，蚀变类型多，规律性十分明显，在横向上具成层性，在垂向上具分带性。其中，膏辉岩化是最为重要的近矿围岩蚀变。矿床类型与宁芜地区陶村式较为相似，成因类型属玢岩型。
The Nihe iron deposit, adjacect to the Tanlu fault, is located in the northwest margin of the Luzong Mesozoic volcanic basin, and is only three kilometers away from the Luohe iron deposit in the southwest. The Nihe iron deposit is a concealed deposit with multi-mineral resources, consisting of one large-scale magnetite ore deposit, one large-scale magnetite-pyrite ore deposit and one medium-scale anhydrite ore deposit. The magnetite ore bodies are situated in the south-west of the deposit, and are layer like or lenticular, occurring in the top of the intrusive dome that caused by the emplacement of pyroxene diorite-porphyrite in the Zhuanqiao formation during late Jurassic. The magnetite-pyrite ore bodies are situated in the north-east of the deposit, with two different occurrences, either in the pyroxene diorite-porphyrite body formed coevally with iron ore body, or in the volcanic rocks of the lower segment of the Zhuanqiao formation relating to strata. The anhydrite ore bodies are situated in the middle of the deposit, occurring as lens in the volcanic rocks of the lower segment of the Zhuanqiao formation. Ore types are so complex that the magnetite ore can be divided into eight natural types, while the magnetite-pyrite ore with five natural types. There are more than 40 minerals in the deposit, and the iron is rich in sulfur and phosphorus, but for the useful ore compositions of Fe, S and anhydrite, there are also other beneficial or harmful compositions in the ore, such as P, V, Ti, Cu, Zn, and so on. Within the Nihe iron deposit, there are intense alterations of the host rocks, and the alterations are widespread and variable, with obvious regularity such as transverse stratification and vertical zonality. In which, the anhydrite pyroxenitization is the most important alteration near the ore. The deposit type is similar to the Taocun-type in Nanjing-Wuhu district, and thus the genesis belongs to porphyrite-type.
zhaowenguang, WU Ming'an, ZHANG Yiyong, WANG Keyou, FAN Yu, WANG Longyun, WEI Guohui, CHE Yingdan.2011. Geological Characteristics and Genesis of Nihe Iron Deposit[J]. Acta Geologica Sinica,85(5):789-801.