|Microfacies type (MFT)/Soil microfabric type (SMT)||Sample No.||Depth (relative depth) Soil Micromorphology (SM)SEM/EDAX||Preliminary Interpretation and Comments|
|Braich y Gornel|
|MFT A1/SMT 1a and 2a||M6||Depth?
SM: heterogeneous with SMT 1a and 2a, amounts of SMT 1a increase and become very dominant upwards;
Microstructure: massive/fine prismatic (fragmented), 45% voids, channels, chambers, poorly accommodated planar voids, with simple and complex packing voids increasing upwards (very low intrapedal porosity);
Coarse Mineral: C:F (Coarse: Fine limit at 10μm), SMT 1a, 40:60; SMT 2a, 30:70, very poorly sorted silt, coarse silt and very fine sand-size quartz and mica, with coarse and very coarse sand-size rock fragments, common siltstone/shale and ferruginous fine sandstone gravel and small stones (25mm);
Coarse Organic and Anthropogenic: trace of fine charcoal; rare to occasional fine plant tissue fragments;
Fine Fabric: SMT 1a: pale dusty brown to darkish dusty brown (PPL), isotropic/very low interference colours (open porphyric, [weakly very finely speckled b-fabric with fine silt], XPL), dark yellowish brown (OIL), moderately humic stained, many amorphous OM, rare very fine charcoal, phytoliths and fungal material present; SMT 2a: darkish yellowish brown to reddish brown (PPL), isotropic/very low interference colours (open porphyric, [weakly very finely speckled b-fabric with fine silt], XPL), darkish brown to very dark brown (OIL), humic stained, abundant amorphous OM, occasional very fine charcoal, phytoliths and fungal material present;
Pedofeatures: Amorphous: abundant fine to medium size Fe and Fe-Mn impregnation (including once-humic material?);
Fabric: abundant thin and broad (2mm) burrows;
Excrements: abundant moderately broad and broad (1-2mm) organo-mineral excrements and patches of occasional very thin mainly organic excrements.
EDAX: Nodular soil with 5.71–13.8% Fe and 17.5–36.1% Mn, sometimes including 0.39–0.59% S and 0.45% P; Excremental soil: 11.7–14.7% Fe and 0.56–1.22% Mn, with sometimes 0.45–0.72% P.
|Contexts 4 over 9 |
Heterogeneous, biologically mixed (burrowed), stony soil with mainly moderately humic silty clay in upper part of slide, and iron- and iron and manganese-stained clayey soil in the lower part (see EDAX). Only trace amounts of fine charcoal, but occasional very fine charcoal and abundant very fine amorphous organic matter in lower soil, which is compact (more recent fragmentation, structure formation in massive soil). Soil is broadly burrowed with moderately broad to broad organo-mineral excrements, with fine pellety excrements upwards.
Biologically mixed junction between more recent humic soil, with phytoliths and phosphate, and lower compact clayey soil which appears to have been humic and contains very fine charcoal (now as very strongly Mn(-Fe)) impregnated soil.
|MFT A2/SMT 1a, 2a and 2b||M8||Depth?
SM: heterogeneous with dominant SMT 1a, and frequent 2a and 2b;
Microstructure: massive, poorly prismatic, with marked pellety; 45%, as M6;
Coarse Mineral: as M6 (C:F, SMT 2b, 20:80), with dominant rounded gravel and small stone-size rock fragments, and strongly weathered shale;
Coarse Organic and Anthropogenic: occasional very fine (200μm) and fine (0.5–0.75mm) roots/root remains (strongly ferruginised);
Fine Fabric: SMT 1a and 1b, as in M6; SMT 2b: dusty orange brown to reddish (PPL), isotropic (open porphyric, undifferentiated b-fabric, XPL), orange, blackish orange (OIL), rare inclusions of amorphous OM, spores, patches of occasional very fine charcoal and fungal material vesicular arbuscular mycorrhizae (birefringent, 250μm);
Pedofeatures: Textural: very abundant reddish limpid clay void coatings (30 μm), mainly Fe-obscured, dominantly associated with SMT 2b, with rare occurrences in matrix soil;
Amorphous: abundant iron impregnation, especially of root traces and 'argillic' SMT 2b; Fabric: very abundant very thin to moderately broad burrowing;
Excrements: very abundant extremely and very thin excrements, many thin excrements.
EDAX: Strongly iron cemented clayey soil (28.0–65.9% Fe, sometimes with 1.09–4.32% Mn and 0.47–0.63% S; nodular soil with 15–32.4% Fe and 0.84–3.17% Mn, sometimes with 0.71% P.
Very heterogeneous, bioworked and fragmented stony soil, with moderately humic silty clay (Fe-stained; EDAX), especially in lower half of slide, and with clayey and clayey argillic soil fragments mainly in middle and upper part of thin section. Argillic soil fragments have abundant thin iron-stained limpid void coatings (EDAX). Occasional very thin ferruginised root remains occur throughout, with fine pellety fabrics dominated lower 'massive' soil (acidiphyle mesofauna). Vesicular arbuscular mycorrhizae (birefringent, 250μm) are present. Only trace amounts of very fine charcoal occur.
Lower half of the slide possibly represents a truncated acidic, weakly podzolic mixed Ah and B(s) horizon, with upwards fragments of strongly iron-stained argillic soil becoming common. Upper soil appearing to be colluvial in character.
Internet Archaeology is an open access journal. Except where otherwise noted, content from this work may be used under the terms of the Creative Commons Attribution 3.0 (CC BY) Unported licence, which permits unrestricted use, distribution, and reproduction in any medium, provided that attribution to the author(s), the title of the work, the Internet Archaeology journal and the relevant URL/DOI are given.
Internet Archaeology content is preserved for the long term with the Archaeology Data Service. Help sustain and support open access publication by donating to our Open Access Archaeology Fund.