The banded iron formation is important to track the Archean to the Paleoproterozoic ocean chemistry. The Banded iron formation is formed by the reduced iron mineral and this triggered by the oxygen from the cyanobacteria. The old model shows that the primary deposition of the Geenalite a Fe (II) mineral was found in some Transvaal Supergroup and Hamersley Group BIF. The Transvaal Supergroup BIF contains as old as 2.52 to 2.43 Ga located in South Africa. The areal extent is 110,000 square km and the max. thickness is 950 m. This huge iron formation is a mystery. Conventional model shows, the deposition of a greenalite is a precursor phase. The following postdepositional oxidation pathways that include early diagenetic fluids and/or infiltration of a meteoric oxidizing fluid and flow parallel to iron-rich layers.
According to the recent hydrogeological box model, shows approximately 2.5 billion-year-old Hamersley Basin of Western Australia, developed to evaluate the plausibility of secondary iron oxidation by the water column oxygen, not from the cyanobacteria.