Revisiting Umhlatuzana Rock Shelter, South Africa:
First geoarchaeological results
Sifogeorgaki Irini
1; Dusseldorp Gerrit
1,21: Leiden University, Faculty of Archaeology 2: Palaeo-Research Institute, University of Johannesburg
ACKNOWLEDGEMENTS
Victor Klinkenberg for his help with find cluster analysisVU Amsterdam Lab for the grain size and LOI analyses
Umhlatuzana stratigraphy
West Profile
Figure 1 Map illustrating sites with MSA-LSA sequences in South
Africa. BMPL: Boomplaas Cave; BP: Border Cave; EBC: Elands Bay Cave; RCC: Rose Cottage Cave; SEH: Sehonghong rock shelter; STR: Strathalan B. rock shelter; UMH: Umhlatuzana rock shelter.
Bell, F. G., & Lindsay, P. (1999). The petrographic and geomechanical properties of some sandstones from the Newspaper Member of the Natal Group near Durban, South Africa. Engineering Geology; Kaplan, J. (1990). The Umhlatuzana Rock Shelter sequence: 100 000 years of Stone Age history. Southern African Humanities, 2(0); Lombard, M., Wadley, L., Jacobs, Z., Mohapi, M., & Roberts, R. G. (2010). Still Bay and serrated points from Umhlatuzana Rock Shelter, Kwazulu-Natal, South Africa. Journal of Archaeological Science, 37(7), 1773–1784; . Map based on SRTM 2000, NASA/JPL/NIMA.
e.sifogeorgakis@arch.leidenuniv.nl
INTRODUCTION
In 2018 we initiated a geoarchaeolog-ical investigation of Umhlatuzana rock shelter. Our aim is to clarify the depo-sitional environment of the Middle and Later Stone Age (MSA-LSA) assemblages (~70 – 20 ka), in light of suggestions of post depositional sediment movement (Kaplan 1990). The Pleistocene sequence shows few visible stratigraphic bound-aries. Sedimentological analysis allows us to evaluate the depositional environ-ment.
RESULTS & CONCLUSIONS
• Discrete high and low find density
lay-ers
• Horizontal orientation of find density
pattern suggests limited
post-deposi-tional movement
• Sedimentary colour difference in
Pleis-tocene due to high-moisture units
• Grain size analysis suggests
contin-uous sedimentation through in situ
weathering of rock shelter
• Low- and high- density layers
proba-bly relate to low- and high-
occupa-tional events
METHODS
Our stratigraphic assessment is based on field observations combined with ge-ospatial data of the piece-plotted finds over 2cm. To assess depositional and post- depositional processes, we have conducted grain-size using a laser de-fractor, pH, and Loss on Ignition analy-ses. Analysis of the piece-plotted finds sheds light into potential mixing of the finds and istinguishes levels of high oc-cupation intensity.
Figure 2 A Ternary graph of grain size, B Particle size distribution curves
for identified stratigraphic units 1b, 5, 7, 9, 10, 11, 15, 33, 48, 50. The mean grain size of the rock shelter was derived from Bell and Lindsay 1999.
10379 16326
Concreted ash layers
Dark Brown sand
16326 +/- 439 2971 32503 41907 70500 70500 60000 41900 33 1a 1b 1c 2 4 23 7 58 57 5 5 56 60 22 41 9 48 15 51 49 14 11 5 50a 12 10 43 Calibrated radiocarbon
and OSL dates (years BP)
(Kaplan 1990, Lombard et. al 2010)
Recent upper layer
In situ combistion features Charcoal-rich layers
Dug-up/ bioturbated features
61
Higher find density layer Lower find density layer
High find density , high moisture layer Low find density, high moisture layer
13 50b 20cm 49b 51b 63 53 10379 16326
Concreted ash layers
Dark Brown sand
16326 +/- 439 2971 32503 41907 70500 70500 60000 41900 33 1a 1b 1c 2 4 23 7 58 57 5 5 56 60 22 41 9 48 15 51 49 14 11 5 50a 12 10 43 Calibrated radiocarbon
and OSL dates (years BP)
(Kaplan 1990, Lombard et. al 2010)
Recent upper layer
In situ combistion features Charcoal-rich layers
Dug-up/ bioturbated features
61
Higher find density layer Lower find density layer
High find density , high moisture layer Low find density, high moisture layer
13 50b 20cm 49b 51b 63 53
ACHATINA (LAND SNAIL) BEADS, IRON AGE
OSTRICH EGGSHELL, NAS-SARIUS KRAUSSIANUS BEAD,
HOLOCENE LSA
BACKED SEGMENT, MSA
UNIFACIAL POINT, MSA
UNIFACIAL POINT, MSA
FRAGMENT OF BIFACIAL POINT, MSA
