Different geological periods, in a similar geological conditions, the formation of the iron ore deposits of the same type; but in different geological periods and tectonic movements of the dominant iron mineral deposit type is different, showing the iron ore depositsthe form is closely related to the characteristics and crustal evolution.
Sedimentary metamorphic iron ore bed
Type of iron ore deposits, also known as metamorphosed sedimentary iron ore deposits, mainly in the Precambrian (Archean and Proterozoic universe) in the old regional metamorphic rocks is a very important type of iron ore in China, its reserves account for 57.8% of the country’s total reserves. And has a large, poor, light, easy to (optional) , ie the deposit scale, low iron content of the ore body exposed to the surface or shallow, easy sorting.
By metamorphic iron silicon built modelling iron ore bed
Subject to construction of metamorphic iron silicon in the iron formation is a multi-layered, 1 to 2 layers, layered, stratiform, lenticular output. Seam thickness of tens to one hundred meters, the thickness of up to 350m. Extend more stable, individual seams up to several tens of kilometers long. Most of the deposit scale, large or extra large.
Iron Ore minerals and quartz banded with black and white striped structure, high degree of metamorphism, the transition to the gneissic. Ore is magnetite quartzite, hematite quartzite, green mud magnetite quartzite, amphibolite magnetite quartzite. Mainly low grade ore, the iron content is generally 25% to 40%. Lean ore, iron-rich iron ore grade of 50% to 60% of different sizes causes.