Table 1.
Summary of site stratigraphy after Galván [24].
Fig 1.
Field photos of selected combustion structures from the combustion structure assemblage.
Fig 2.
Combustion structures of unit Xb—El Salt.
a) Georeferenced orthophotograph extracted from 3D photogrammetric model of the site created in the 2017 field season showing the combustion structures selected for this study (georeferenced BL perimeters) and associated micromorphology and biomarker samples. b) Georeferenced orthophotograph (same as in a) of the whole site, with indicated location of the area of interest for this study. c) Overview picture of the surrounding area of the site. Arrow indicates the position of the site. d) Overview of the site, arrow indicates the area of interest. e) Geographical location of El Salt within Spain.
Fig 3.
Schematic drawing showing the stratigraphic position of the selected combustion structures.
Combustion structures as observed in the field with facies thickness in cm (*).
Table 2.
Summary of the lipid fractionation procedure and reconstitution for chromatographic analysis.
Table 3.
Components identified in the combustion structures and in the sediment of Xb.
Fig 4.
Components identified in the micromorphological samples.
a) wood ash (PPL), b) wood ash (XPL), c) needle fiber calcite (XPL), d) ashes (PPL), ashes (XPL), f) unidentified square black particles (PPL), g) burnt bone (PPL), h) burnt bone (XPL), i) animal fat-derived char (PPL), j) fibrous coprolite (PPL), k) fibrous coprolite (XPL), l) blackened plant particles (PPL), m) burned tufa (PPL), n) burned tufa (XPL), o) celtis australis seed coats (PPL).
Fig 5.
a) fibrous coprolitic matrix (PPL), b) fibrous coprolitic matrix (XPL), c) phosphatic matrix (PPL), d) phosphatic matrix (XPL).
Table 4.
Microfacies types (MFT).
Table 5.
TC, TIC and TOC.
Fig 6.
N-alkane profiles of combustion feature facies in numerical order from H44 to H54.
Abundances of alkanes with chain lengths from 17 to 35 in μg/gds with three different scales on the y-axis. Error ranges are shown according to their standard deviation. For H50 BL3 and H50 BL4 the error ranges are lower than 0.004 μg/gds. Graphs show total alkane content (μg/gds), CPI and alteration group.
Fig 7.
N-alkane profiles of combustion feature facies in numerical order from H55 to H61 including control samples.
Abundances of alkanes with chain lengths from 17 to 35 in μg/gds with three different scales on the y-axis. Error ranges are shown according to their standard deviation. For H55 BL1 and C2 the error ranges are lower than 0.004 μg/gds. Graphs show total alkane content (μg/gds), CPI and alteration group.
Fig 8.
δ13C compound specific alkane profiles.
Combustion structures on the x-axis and δ13C values on the y-axis, displaying the isotopic value of the alkane nC29 and nC31 with error ranges according to the standard deviation.