Fig. 3.

(A) Photograph of east profile corresponding to squares R/Q28 showing a detailed view of stratum 10. Box indicates approximate location of thin section (B), exhibiting three microstratigraphic units (microfacies): (1) bottom sandy silt and clay mixed with ashed plant material, dispersed wood ash, and bone fragments; (2) clay aggregates and fragments; and (3) rounded aggregates of sandy silt. Large red rectangular box indicates the location of boundary between microfacies 1 and 2, which is enlarged immediately above in C. Small blue box indicates subsurface location with wood ash pieces dispersed in silty sediment (enlarged in H). (C) Magnification of contact area between microfacies 1 and 2 in thin section shown in B shows characteristic of erosion and successive stabilized surface, on top of which are ashed plant material and bone fragments shown in micrographs (D–J). Boxes mark the location of microphotographs shown in D–G, I, and J (PPL). (Scale bar: 1 cm.). (D) Micrograph of fragments of ashed plant material (PPL). (Scale bars: 1 mm.) (E) Micrographs of lump of calcitic wood ash with typical ash rhombs (oxalate pseudomorphs) and prisms at the contact between microfacies 1 and 2 (PPL). (Scale bar: 500 μm.). (F and G) Micrographs of fragments of ashed plant material (PPL) (Scale bars: 1 mm.) (H) Sediment from microfacies 1, with fragmented ashed plant material and dispersed wood ash rhombs and prisms (oxalate pseudomorphs; PPL). (Scale bar: 1 mm.) (I) Micrograph of contact area between microfacies showing clay aggregates in microfacies 2 and organometallic area (degraded charred material?) and bone fragments resting on the surface of microfacies 1. (Scale bar: 1 mm.). (J) Micrograph of bone fragment. (Scale bar: 100 μm.)