Diagenetic reddening of Early Eocene paleosols on King George Island, Antarctica

The objective of this study was to determine if the Early Eocene paleosols on King George Island, Maritime Antarctica, have acquired their reddish color during the paleopedogenesis, by burial diagenesis and/or by heating of a covering lava flow. We used micromorphology, diffuse reflectance spectroscopy, X-ray diffraction, and mineral magnetic properties to identify the iron oxides in these paleosols. These are weakly/moderately developed paleosols formed on a basaltic tephra under a cool humid paleoclimate, therefore, prone to ferrihydrite and goethite rather than hematite formation. However, the iron oxide assembly was dominated by maghemite and hematite. Nevertheless, the large grain size and high crystallinity of hematites suggested they are rather diagenetic than pedogenic.