Soil geochemistry on an early Swahili daub house, Zanzibar

I came across an interesting paper by Frederica Sulas and others (2019) who conducted a geoarchaeological study on an early Swahili (medieval) daub house at Unguja Ukuu, Zanzibaar (7th-14th c. AD). The study integrated geochemical, artefact distribution, and phytolith analyses. For the geochemical study pH, Loss on Ignition, and multi-element (ICP-MS) analyses were conducted on bulk sediment samples. The samples were derived from both the archaeological site (indoor and outdoor of the daub house structure) and the surrounding landscape. The main objective of the research was to investigate spatial organisation and activities within the house and test high-resolution systematic sampling strategies in this type of contexts.

 

View of the excavation trench and the 50 cm interval sampling grid (Sulas et al. 2019)

 

The use of multi-proxy geoarchaeological techniques helps to further explore the microarchaeological record that would otherwise not be visible with the naked eye. Various anthropogenic everyday activities leave microscopic and elemental traces that can be present even in seemingly homogeneous archaeological deposits. For example, this paper considers the use of Rare Earth Elements (REEs) as indicators of human remains (e.g. nails, skin, hair), seaweed, shell, sand, and animal manures (as ref. by Sulas et al. 2019, 34).

 

Distribution of Sm, V, Na, and K chemical concentrations (Sulas et al. 2019)

 

The REEs in this study reveal significant concentration patterning, and when combined with the other results can provide insight into the way people lived on the site, their subsistence strategies, and their spatial organisation. All in all, this paper showcases another example of how integrating various geoarchaeological techniques can develop a deeper understanding of various aspects of archaeological sites. 

 

Reference

Sulas, Kristiansen, and Wynne-Jones. “Soil Geochemistry, Phytoliths and Artefacts from an Early Swahili Daub House, Unguja Ukuu, Zanzibar.” Journal of Archaeological Science 103 (2019): 32-45.

Leiden GeoArch: New geoarchaeology group

Exciting news for the Faculty of Archaeology, Universiteit Leiden: a newly founded group, Leiden GeoArch, that plans to promote and discuss matters concerning geoarchaeology!

The first event will have the format of a lunch-lecture where Victor Klinkenberg will present his work on micromorphology of Mycenaean chamber tombs (March 4th/ 12h/ Van Steenis, Leiden).

What a wonderful opportunity to get inspired by various applications of geoarchaeological techniques to answer archaeological questions!

GeoarchLeidenMarch2019Noschedule
Leiden GeoArch: Micromorphology of Mycenean Chamber Tombs poster

Various lectures and activities are on the schedule for the near future including my talk “Micromorphology for dummies” coming up May 6!

GeoarchLeidenMarch2019programme
Spring agenda 2019 for the LeidenGeoarch group: Faculty of Archaeology, Universiteit Leiden

 

Stay tuned!