Historical-Genetic Analysis of the Formation of High-Grade Iron Ores and Related Bauxites in the Kursk Magnetic Anomaly (Russia)

Abstract

High-grade iron ores and bauxites of the Kursk magnetic anomaly (KMA) were formed in weathering crusts on the Early Precambrian ferruginous quartzites and shales, i.e., banded iron formation (BIF). Thus far, weathering crusts on the BIF were considered separately, although they formed simultaneously and represent a single sequence in each ore region. Therefore, it is of great interest to compare the coeval weathering crusts on rocks of the formation under consideration for a complex prediction of high-grade iron ores and bauxites. The obtained results showed that the BIF-hosted iron ores were formed during all stages of crust formation in the Paleozoic and such ores can be predicted throughout the KMA, whereas bauxites were only formed in inter-ore shales on the southwestern flank of the anomaly.