Fig. 5: Micromorphological analysis results.

a View of the sawn face of the sample from which five thin sections were made. The microstratigraphy consists of four units (mc. 1 to mc. 4). In the ploughed horizon (mc. 3), at least three generations of furrow bottoms are recognized by analysis (I–III). At the top, the last generation is filled in by light-grey alluvial sediment (mc. 4) and corresponds to the lineations observed during excavation. b Microscopic view of the transition level (mc. 2). Fragmented and punched fine gravels in situ indicate an implementation with a rudimentary tool. c At the base of the ploughed soil (mc. 3), gravels are bedded according to the lower contact. They correspond to the bottom of ploughing furrows. Bone fragments are probably included in the soil as fertilizer. d View of the contact between, at the base, the ploughed horizon with humic matrix (mc. 3) and, at the top, the carbonated fill (mc. 4) of the upper furrows (III). Gravel layering is also found at the boundary. b, c PPL, d XPL.