Iron Oxides Chemistry from Highgrade Iron Ore, Iron Quadrangle
22nd Goldschmidt Geochemistry Conference Abstract
Most of the high-grade iron ore deposits in the Iron Quadrangle (IQ), Brazil are hosted by itabirites of the Caue Formation, a Paleoproterozoic Lake-Superior type Banded Iron Formation. The IQ was affected by two main orogenies, the Transamazonian (2.6 – 2.0 Ga) and the Brasiliano (0.7 – 0.45 Ga) resulting in a western low strain and an eastern high-strain domain. Iron ore bodies in the western domain are dominated by early-stage martite and granoblastic hematite, whereas ore bodies of the eastern domain contain mainly late-stage microplaty hematite and specularite.