卢氏张家山铁矿床为河南卢氏地区矿产远景调查项目中首次发现的一个褐铁矿床,铁矿床中伴有广泛的 Mo、Zn 地球化学异常。赋矿围岩为震旦系东坡组碳质含量较高以粉砂质成分为主的一套浅变质岩系组合。铁矿石和赋矿围岩含碳质千枚岩的 SiO2/Al2 O3值相近,碳质千枚岩n(Al2 O3)/n (Al2 O3+Fe2 O3)值大部分为0.6~0.9；SiO2/Al2 O3值大多数<5,绝大多数样品中K2 O含量大于 Na2 O；微量元素 Sr/Ba 值显示陆源沉积为主；稀土元素配分曲线形态相似,呈轻稀土富集型并有明显的 Eu 亏损。铁矿形成于相对平静(波动较小)的氧化与弱还原交替的半封闭局限海盆次深海环境,铁矿石和含碳质千枚岩主要来自于陆源,少量可能与火山作用相关,中元古界官道口群巡检司组白云质灰岩形成环境为海相沉积,与铁矿体和含碳质千枚岩具有不同的物质来源。%The Zhangjiashan iron deposit in Lushi country is a limonite deposit,which is first found in the processes of implementing the metallogenic prospective survey in Lushi area of Henan Province.There are several limonite ore-bodies in the Zhangjiashan deposit,which are as-sociated molybdenum and zinc abnormities. The wall rocks of iron ore-bodies are a set of epimeta-morphic rock series occurred in Dongpo Formation of Sinian System,which is dominated by silty-materials with high carbonaceous.The analyzed results show that,the SiO2/Al2 O3 values of the carbonaceous phyllite from iron ore and wall rock are similar,the n (Al2 O3 )/n (Al2 O3 +Fe2 O3 ) values mainly range from 0.6 to 0.9,most of SiO2/Al2 O3 ratios are less than 5,and the K2 O con-tents are more than Na2 O contents in the most samples. For the trace elements,the Sr/Ba ratio-sindicate that these carbonaceous phyllites were mainly sourced from terrigenous sediment.The rare earth distribution patterns of these phyllites are similar,showing the enrichment of LREE and the obvious loss of Eu.The iron was formed in the semi-closed limited oceanic basin-bathyal environment,which was relatively quiet (less volatile)and alternated with oxidation and weak re-duction. The iron ore and C phyllite arederived from terrigenous sediment,with small part of them might be related with volcanism. The dolomitic limestones in the Xunjianshi Formation of Guandaokou Group were the results of marine deposition,which may be different from iron ore and C phyllite.
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