宁夏中南部铁矿地质特征及成矿规律探讨

宁夏中南部主要包括中卫市和固原市，该区属香山一卫宁北山一固原铜、金、铁、铅锌多金属成矿带，也是宁夏重要的金属矿产矿集区。研究区大地构造位于北祁连褶皱系走廊过渡带东段。铁矿床类型主要有中低温热液充填交代型和地表浅部氧化淋滤型；含矿层位主要为下石炭统前黑山组、臭牛沟组以及上石炭统土坡组，其沉积建造主要为粉砂岩一泥岩建造、石英砂岩建造、碳酸盐岩建造；矿体主要沿断裂分布，呈脉状、透镜状和似层状；具有原生矿石和氧化矿石两种矿石类型。成矿物质主要来源于地层；褶皱和断裂构造为成矿流体提供了有利的运移通道和淀积空间，从而对矿体的空间展布起到了控制作用；岩浆热液和围岩蚀变对成矿物质的聚集以及重新分配、改造起到了重要的作用。

Geological Characteristics and Mineralization Regularities of Iron Deposits in Central-Southern Ningxia

Central-southern Ningxia includes Zhongwei and Guyuan cities, which is a part of the Xiangshan-Weiningbeishan-Guyuan Cu-Au-Fe-Pb-Zn polymetallic ore belt, and is also an important metal deposit concentration area. It is located in the eastern section of the North Qilian fold belt. The iron ore deposits are dominated by low-middle temperature hydrothermal metasomatic and shallow oxidative leaching ones. The orebodies mainly occurred in the lower Carboniferous Qianheishan and Chouniugou Formations and the upper Carboniferous Tupo Formation. The sedimentary formations are mainly siltstone-shale, quartz sandstone and carbonate Formations. The ore bodies are distributed along the fractures, and display vein, lenticular and bedded textures. The ores can be classified into the primary and oxidized ores. The ore-forming materials are originated from the strata. The folds and faults provided favorable fluid migration channels and deposition space, and thus controlled the spatial distribution of the ore bodies .The magmatic-hydrothermal fluid and wall rock alteration played an important role in the accumulation, redistribution and reformation of the ore-forming materials.