Early in the Earth’s development, the atmosphere contained no oxygen. Yet the iron dissolved in the oceans was oxidized in gigantic quantities and deposited as rock. It can be seen today, for example, as banded iron ore in South Africa. Early in the Earth’s development, the atmosphere contained no oxygen. Yet the iron dissolved in the oceans was oxidized in gigantic quantities and deposited as rock. It can be seen today, for example, as banded iron ore in South Africa. Earth Sciences Environment Phys.org – latest science and technology news stories