Key micromorphological features in the open-air sites.

(a) Scan of MM_OA1-House showing two thin sections. The numbers indicate the key micromophological features described in Table 1. Note that no. ‘3’ is a thin horizon marked by the arrow. The letter ‘b’ indicates the location of the microphotograph; (b) Microphotograph of the horizon interpreted as the house floor showing two thin layers of pure oriented clay coating with dusty silty clay and humified organics above and between the clay layers. Note how quartz grains and organics are trampled into the clay layers. The photograph was taken in Plane Polarized Light (PPL); (c) Scan of MM_OA1-Terrace thin section. The numbers indicate the various fabrics identified and described in Table 1. Note the smaller size of the irregular aggregates and the horizontal orientation of the cracks in fabric 2 compared with fabric 1 where cracks are randomly oriented. Fabric 2 shows several past terrace surfaces. The rock fragment at the most top part of fabric 3 is showing iron impregnation on its surface indicating close proximity to the surface; (d) Scan of MM_OA1-Slope thin section. Fragments of well-preserved charcoals can be seen throughout the thin section. Note the orientation inclined with the slope towards the left side and the lack of clear layering; (e) A microphotgraph of a charcoal found in MM_OA1-Slope. The charcoal is covered by clay and yet show signs of disintegration. This taphonomic process indicate that while the charcoal is protected and covered by the local sediment, probably acidic conditions are affecting the charcoal and its preservation (PPL); (f) Scan of MM_OA2-Terrace thin section. The upper part of the sample show a crumbly structure and evidences to intensive biological activity which disrupt the sediment structure. Note the higher amount of organics in the upper part. The greyish material on the left is the remains of paper attached to the sediment as part of the sampling process; (g) Microphotograph showing the replacement of organic material with clay and secondary iron (PPL); (h) same microphotograph as ‘g’ (XPL).