The seasonality of birth, a key parameter when addressing past domestic livestock management, can be investigated through serial stable oxygen isotope analysis in tooth enamel. The assessment of the season of births requires furthermore the availability of modern reference data set, existing for cattle, sheep, pigs or llamas. The ancient site of Sagalassos, in the Taurus Mountains (SW Turkey), has delivered a large assemblage of sheep and goat remains. The osteological analysis revealed a predominance of goat over sheep, with a ratio varying between 65 and 90% over time. Goats and sheep were kept at an old age for the production of milk, wool/hair, as well as for horn-working and hide exploitation. A stable oxygen isotope (δ18O) analysis focussing on mandibular M2s was undertaken to investigate goat and sheep livestock demographic management during the Early Byzantine period (450-680 CE). ZooMS was used to confirm specific attribution of selected specimens (ten goats, eight sheep). Ten modern hair goats collected in the late 1990s in the context of a research project on small ruminant herd management in the Eastern Mediterranean were also sampled to provide a modern comparative for the assessment of birth season. The modern goat δ18O sequences were modelled according to Balasse et al. (2012) and compared with the existing sheep reference data set. The comparison suggests a different timing in the isotope record between sheep and goats and argues for the use of species-specific comparative for the assessment of birth season in archaeological herds. The comparison of the modern and archaeological goat δ18O sequences indicate a quite restricted season of births in spring for the latter. On the contrary, sheep births were spread out over roughly six months, from late winter/early spring to early-/mid-summer. More modern goat comparatives are needed to enrich this dataset. Keywords: Stable oxygen isotope, tooth enamel, birth seasonality, goat, Sagalassos.
Located in
Library
/
RBINS Staff Publications 2023
The discovery of a bitumen bed within the Silurian Bonne Esperance Formation near the city of Huy (Belgium) is the first clear evidence for a petroleum system in Belgium. The studied section near the city of Huy (Belgium) is part of a larger structural unit called the Condroz inlier. This structural unit is a wedge of Ordovician to Silurian aged marine sediments which was thrusted up along the Midi detachment fault during the Hercynian orogeny and forming the Ardennes Massif (Adams & Vandenberghe, 1999). To understand the geological processes involved in the formation of the bitumen bed, the Bonne Esperance Formation was logged and 82 samples were collected for XRF chemostratigraphy, five samples were collected (Figure 1, pictures 1-5) for biostratigraphic purposes and one sample was taken from the bitumen itself. ICP-MS, TOC, Rock-Eval pyrolysis and Gamma-ray measurements are underway to quantify the source rock potential of the Bonne Esperance Formation. Preliminary XRF measurements already show that especially the lower part of the Bonne Esperance Formation is enriched in elements linked to anoxic conditions/enrichment of organic material, which indicates that the Bonne Esperance Formation itself is the likely candidate source rock for the bitumen. The sample from the bed which includes the bitumen has already been tested to confirm the nature of the bitumen material. The sample was crushed and heated in a vial and the released hydrocarbons were then ignited with a flame (Figure 1, picture 6C). The First occurrence of the graptolites of the Family Monograptidae was used to pinpoint the location of the Ordovician-Silurian boundary (Akidograptus Ascensus zone at sample 4) (Maletz, 2017). Given the current results and the ongoing analyses a picture emerges of the Silurian of the Condroz inlier as being Belgium’s first and to date only petroleum system.
Located in
Library
/
RBINS Staff Publications 2021
