Fig. 5

X-ray tomographic images of an Oseberg sample showing distribution of alum salts in the three main directions: transverse (a), tangential (b) and radial (c). Brighter regions (circled) indicate another inorganic compound likely derived from the alum treatment. Images show alum’s patchy longitudinal distribution (b, c). The bar shows 50 μm. Acquired at the TOMCAT beamline, Paul Scherrer Institute (PSI), Switzerland by HK, MC and SB. Rendered by SB