Late Holocene Stalagmite and Tufa Climate Records for Wonderwerk Cave: Relationships Between Archaeology and Climate in Southern Africa

Abstract

Horizontal cores from a large stalagmite and two tufa deposits in the entrance to Wonderwerk Cave, South Africa, dated by radiocarbon methods, have provided climate proxy data on late Holocene environments near the cave. The δ18O and δ13C time series from stalagmite Core WW1–3 and tufa Core WW3 correlate well with isotope records for other sites in the summer rainfall zone of southern Africa and suggest that late Holocene warm periods in the Northern Hemisphere, including the Medieval Warm period, Roman Warm period, and Minoan Warm period, were times of increased moisture in this rainfall zone. In contrast, late Holocene cold intervals in the Northern Hemisphere, including the Dark Ages Cold period and Sub-Atlantic Cold period, were times of drier climate in the summer rainfall zone. Comparison of the Wonderwerk records with information on human settlement patterns, agricultural expansion or decline, and population growth or decline, shows that growth occurred preferentially during wetter climate periods and declines, including the abandonment of the important town of Mupungubwe in the Shashe-Limpopo area of northeast South Africa and the fall of Great Zimbabwe, which occurred during periods of low precipitation.

Résumé

Une grande stalagmite venant de la grotte de Wonderwerk, en Afrique du Sud, a été carottée horizontalement et est comparée avec deux autres dépôts de tuf venant de la meme grotte pour comprendre la variation climatique aux alentours de la grotte durant la fin de l’Holocene. Ces archives geologiques ont été datés par la methode 14C. Les variations isotopiques, particulierement δ18O et δ13C de la carotte WW1–3 et celles du tuf WW3, presentent une bonne resemblance avec d’autres donnees paleoclimatiques obtenues des autres site climatiques de la zone chaude et humide de l’Afrique australe. La comparaison suggere que la periode chaude de la fin de l’Holocene connue dans l’hemisphere nord, comme la période chaude médiévale, Roman Période Chaude, et Minoan Période Chaude, correspond a une periode tres humide aux alentours de Wonderwerk. Par contre, les periodes froides de la meme interval, comprenant Dark Ages Période Froide et Sous-Atlantique Période Froide, correspondent a des periodes seches a Wonderwerk. Il est a noter que les types d'établissements humains, l'expansion ou le déclin agricole, et la croissance de la population ou de déclin, montre que la croissance ont eu lieu préférentiellement pendant les périodes et les baisses de climat plus humide, y compris l'abandon de l'importante ville de Mupungubwe dans la zone Shashe-Limpopo du nord-est en Afrique du Sud et la chute du Grand Zimbabwe, a eu lieu pendant les périodes de faibles précipitations.

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Acknowledgments

Liora Kolska and Michael Chazan are thanked for involving us in the Wonderwerk Cave research and for continued encouragement and patience. We also thank the previous owners (the Bosman family) of Wonderwerk Cave, especially Susan Joubert, for their permission to work at the cave and for their friendship and hospitality during the drilling of the cores. Peter Beaumont of the McGregor Museum in Kimberley obtained permission from the Museum for the work at Wonderwerk Cave in 1999 and assisted with the drilling of cores; his help is acknowledged and greatly appreciated. Our thanks to three reviewers who provided suggestions that significantly improved the paper. The research was supported by US National Science Foundation Grant No. 0725090 to Brook.

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Archaeological time period: late Holocene; the last 3,500 years

Country and region discussed: South Africa and southern Africa

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Brook, G.A., Railsback, L.B., Scott, L. et al. Late Holocene Stalagmite and Tufa Climate Records for Wonderwerk Cave: Relationships Between Archaeology and Climate in Southern Africa. Afr Archaeol Rev 32, 669–700 (2015). https://doi.org/10.1007/s10437-015-9210-y

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Keywords

  • Stalagmite
  • Tufa
  • Climate change
  • Archaeology
  • Isotopes
  • Cave