Ion-induced reduction of metal oxides is a widely reported phenomenon. Previous studies have used surfaces-sensitive techniques such as x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) to link the phenomenon to the energy of formation of an oxide, preferential sputtering and bombardment-induced segregation of different elements. This study investigates the effective depth of ion-induced reduction on representative iron oxides (hematite Fe2O3, goethite FeOOH and magnetite Fe3O4) using synchrotron radiation. By varying the incident photon energies, oxidation states at different depths can be probed with consistent charge compensation. The spectra are resolved on energy sensitive Tougaardï¿½s background, in comparison to a more convenient Shirleyï¿½s one. Complementary information is also obtained using x-ray absorption of near-edge structure (XANES). The study aims to establish a correlation between ion doses and the extent of reduction induced by them. This understandings may lead to a novel way to include a structurally integrated metallic state in a surface thin film of oxides.