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Includes bibliographical references (p. 241-272).This thesis investigates the validity of oxygen ... more Includes bibliographical references (p. 241-272).This thesis investigates the validity of oxygen isotope analysis for the gastropod Turbo sarmaticus (operculum and shell) and the bivalve Donax serra to reconstruct sea surface temperatures. These are the species most commonly retrieved from archaeological assemblages of the South Coast of South Africa. The material analysed for this thesis includes modern and archaeological shells from Pinnacle Point, Mossel Bay. Evidence of human occupation of coastal caves here dates as far back as 164 kya. Specimens analysed for this study date between 114 and 91 ky. Analysis of edge increments shows that all the archaeological specimens were collected in winter and/or in spring and autumn, pointing to seasonal exploitation; the first documentation of this kind of seasonal scheduling of activities in Middle Stone Age sites in South Africa
Palaeogeography, Palaeoclimatology, Palaeoecology, 2017
The large marine gastropod Turbo sarmaticus was (and still is) an important food item for coastal... more The large marine gastropod Turbo sarmaticus was (and still is) an important food item for coastal foragers along the south coast of South Africa. Opercula of this species are well-preserved in both Holocene and Pleistocene archaeological sites, offering the opportunity to reconstruct past sea surface temperatures from δ 18 O of shell carbonate over much of the last glacial cycle. We have analysed δ 18 O and δ 13 C in 16 opercula and one shell of modern animals collected alive from an area with good SST records, in order to explore how reliably this species records water temperature through the year and to investigate possible 'vital effects' that may influence the isotope record. We find that T. sarmaticus deposits aragonite in both operculum and shell in oxygen isotopic equilibrium with seawater. Operculum δ 18 O values of this species reliably reflect water temperatures between c.14 and 24°C, although they do not always capture temperature extremes, especially in winter, likely due to slower growth under stressful growth conditions. These thresholds probably alter according to factors such as variations in nutrient supply. The averaged maximum and minimum values across the set of sixteen serially sampled opercula very closely approximate the temperatures of the warmest and coolest months and therefore provide a good measure of the seasonal temperature range, and of mean annual SST. δ 18 O of edge increments can, to some extent, be used to indicate season of collection, within the broad categories of warmer/cooler seasons.
Radiocarbon, 2004
The eruption of the volcano at Thera (Santorini) in the Aegean Sea undoubtedly had a profound inf... more The eruption of the volcano at Thera (Santorini) in the Aegean Sea undoubtedly had a profound influence on the civilizations of the surrounding region. The date of the eruption has been a subject of much controversy because it must be linked into the established and intricate archaeological phasings of both the prehistoric Aegean and the wider east Mediterranean. Radiocarbon dating of material from the volcanic destruction layer itself can provide some evidence for the date of the eruption, but because of the shape of the calibration curve for the relevant period, the value of such dates relies on there being no biases in the data sets. However, by dating the material from phases earlier and later than the eruption, some of the problems of the calibration data set can be circumvented and the chronology for the region can be resolved with more certainty.In this paper, we draw together the evidence we have accumulated so far, including new data on the destruction layer itself and for ...
Interdisciplinary Contributions to Archaeology, 2011
... South African Journal of Science 99: 2437. Parkington, J. 2008. Limpet sizes in Stone Age ar... more ... South African Journal of Science 99: 2437. Parkington, J. 2008. Limpet sizes in Stone Age archaeological contexts at the Cape, South Africa: changing environment or human impact? in A. Antczak and R. Cipriani (eds) Early Human Page 15. 419 ...
Journal of Human Evolution, 2014
Radiocarbon, 2004
Given the non-monotonic form of the radiocarbon calibration curve, the precision of single 14C da... more Given the non-monotonic form of the radiocarbon calibration curve, the precision of single 14C dates on the calendar timescale will always be limited. One way around this limitation is through comparison of time-series, which should exhibit the same irregular patterning as the calibration curve. This approach can be employed most directly in the case of wood samples with many years growth present (but not able to be dated by dendrochronology), where the tree-ring series of unknown date can be compared against the similarly constructed 14C calibration curve built from known-age wood. This process of curve-fitting has come to be called “wiggle-matching.”In this paper, we look at the requirements for getting good precision by this method: sequence length, sampling frequency, and measurement precision. We also look at 3 case studies: one a piece of wood which has been independently dendrochronologically dated, and two others of unknown age relating to archaeological activity at Silchest...
Includes bibliographical references (p. 241-272).This thesis investigates the validity of oxygen ... more Includes bibliographical references (p. 241-272).This thesis investigates the validity of oxygen isotope analysis for the gastropod Turbo sarmaticus (operculum and shell) and the bivalve Donax serra to reconstruct sea surface temperatures. These are the species most commonly retrieved from archaeological assemblages of the South Coast of South Africa. The material analysed for this thesis includes modern and archaeological shells from Pinnacle Point, Mossel Bay. Evidence of human occupation of coastal caves here dates as far back as 164 kya. Specimens analysed for this study date between 114 and 91 ky. Analysis of edge increments shows that all the archaeological specimens were collected in winter and/or in spring and autumn, pointing to seasonal exploitation; the first documentation of this kind of seasonal scheduling of activities in Middle Stone Age sites in South Africa
Palaeogeography, Palaeoclimatology, Palaeoecology, 2017
The large marine gastropod Turbo sarmaticus was (and still is) an important food item for coastal... more The large marine gastropod Turbo sarmaticus was (and still is) an important food item for coastal foragers along the south coast of South Africa. Opercula of this species are well-preserved in both Holocene and Pleistocene archaeological sites, offering the opportunity to reconstruct past sea surface temperatures from δ 18 O of shell carbonate over much of the last glacial cycle. We have analysed δ 18 O and δ 13 C in 16 opercula and one shell of modern animals collected alive from an area with good SST records, in order to explore how reliably this species records water temperature through the year and to investigate possible 'vital effects' that may influence the isotope record. We find that T. sarmaticus deposits aragonite in both operculum and shell in oxygen isotopic equilibrium with seawater. Operculum δ 18 O values of this species reliably reflect water temperatures between c.14 and 24°C, although they do not always capture temperature extremes, especially in winter, likely due to slower growth under stressful growth conditions. These thresholds probably alter according to factors such as variations in nutrient supply. The averaged maximum and minimum values across the set of sixteen serially sampled opercula very closely approximate the temperatures of the warmest and coolest months and therefore provide a good measure of the seasonal temperature range, and of mean annual SST. δ 18 O of edge increments can, to some extent, be used to indicate season of collection, within the broad categories of warmer/cooler seasons.
Radiocarbon, 2004
The eruption of the volcano at Thera (Santorini) in the Aegean Sea undoubtedly had a profound inf... more The eruption of the volcano at Thera (Santorini) in the Aegean Sea undoubtedly had a profound influence on the civilizations of the surrounding region. The date of the eruption has been a subject of much controversy because it must be linked into the established and intricate archaeological phasings of both the prehistoric Aegean and the wider east Mediterranean. Radiocarbon dating of material from the volcanic destruction layer itself can provide some evidence for the date of the eruption, but because of the shape of the calibration curve for the relevant period, the value of such dates relies on there being no biases in the data sets. However, by dating the material from phases earlier and later than the eruption, some of the problems of the calibration data set can be circumvented and the chronology for the region can be resolved with more certainty.In this paper, we draw together the evidence we have accumulated so far, including new data on the destruction layer itself and for ...
Interdisciplinary Contributions to Archaeology, 2011
... South African Journal of Science 99: 2437. Parkington, J. 2008. Limpet sizes in Stone Age ar... more ... South African Journal of Science 99: 2437. Parkington, J. 2008. Limpet sizes in Stone Age archaeological contexts at the Cape, South Africa: changing environment or human impact? in A. Antczak and R. Cipriani (eds) Early Human Page 15. 419 ...
Journal of Human Evolution, 2014
Radiocarbon, 2004
Given the non-monotonic form of the radiocarbon calibration curve, the precision of single 14C da... more Given the non-monotonic form of the radiocarbon calibration curve, the precision of single 14C dates on the calendar timescale will always be limited. One way around this limitation is through comparison of time-series, which should exhibit the same irregular patterning as the calibration curve. This approach can be employed most directly in the case of wood samples with many years growth present (but not able to be dated by dendrochronology), where the tree-ring series of unknown date can be compared against the similarly constructed 14C calibration curve built from known-age wood. This process of curve-fitting has come to be called “wiggle-matching.”In this paper, we look at the requirements for getting good precision by this method: sequence length, sampling frequency, and measurement precision. We also look at 3 case studies: one a piece of wood which has been independently dendrochronologically dated, and two others of unknown age relating to archaeological activity at Silchest...