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Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successionsBarbolini, Natasha 12 June 2014 (has links)
The Main Karoo Basin of South Africa is renowned for its exceptional palaeontological record and while its vertebrate fossils have been extensively researched, Karoo floras have received considerably less attention. Poor yields of palynomorphs from the Beaufort and “Stormberg” groups have complicated the task of erecting a comprehensive palynozonation scheme for the Karoo Supergroup. For this study, 65 palynologically productive samples from the Dwyka, Ecca, Beaufort and “Stormberg” groups allowed for systematic descriptions of all palynomorphs, as well as the ranges of the different taxa through the entire Karoo stratigraphic succession. Taxa with restricted ranges are useful for biostratigraphic correlation and these palynomorphs were used to delineate microfloral zones for the Karoo basin. The Dwyka Group contains high numbers of acritarchs and is generally low in species diversity. Useful biostratigraphic taxa for the Ecca Group include Cannanoropollis, Hamiapollenites, Platysaccus and Striatopodocarpites. Aratrisporites is a marker for the Latest Permian / Early Triassic Beaufort Group, while Cyathidites, Dictyophyllidites, Equisetosporites and Uvaesporites are indicators of the Late Triassic / Early Jurassic “Stormberg” Group. Palynostratigraphic zones correlate largely with the Karoo vertebrate biozones and severe and sudden extinction events are recognised among Karoo palynomorphs in the upper Tapinocephalus and Dicynodon assemblage zones. The first comprehensive palynological biozonation scheme for the Main Karoo Basin is proposed and the study provides a broad overview of Gondwanan Carboniferous - Jurassic floras. This study demonstrates that palynology is useful in correlating age equivalent lithostratigraphic units in the proximal and distal sectors of the Karoo Basin. Microfloras from previous South African studies are integrated within the proposed palynostratigraphic scheme, and palynological signatures of the various Karoo formations are shown to be consistent. Despite the constraints of floral provincialism, South African microfloras can be correlated to selected Gondwanan biozonations from Australia, Africa, Antarctica, New Zealand and South America. Future studies should focus on sampling more intensively over smaller stratigraphic intervals, which will assist in the correlation of time equivalent lithostratigraphic units in the different sectors of the basin, thus aiding in refinement of basin development models.
Key words: palynology, Karoo, vertebrate biozones, stratigraphy, Gondwana
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Middle Permian continental biodiversity changes as reflected in the Beaufort Group of South Africa: a bio-and lithostratigraphic review of the Eodicynodon, Tapinocephalus and Pristerognathus assemblage zonesDay, Michael Oliver 04 March 2014 (has links)
The fluvio-lacustrine rocks of the Beaufort Group, South Africa have long been
known for their tetrapod fossil record, which is the richest and most complete
Middle Permian to Middle Triassic record for any terrestrial sequence in the world.
The abundance of fossil material has enabled the Beaufort Group to be
biostratigraphically subdivided into between 8 and 10 tetrapod assemblage zones, of
which the lowest three (Eodicynodon, Tapinocephalus and Pristerognathus) are attributed to
the Middle Permian. These lower assemblage zones record the earliest therapsiddominated
faunas and, because they were recorded during a largely uninterrupted
period of deposition, make the Beaufort Group the only place in the world where
biodiversity change through the terrestrial Middle Permian can be effectively studied.
In the last two decades, much interest has focused on an extinction of marine
invertebrates at or close to the end of the Middle Permian (Guadalupian epoch), but
the existence of a concurrent extinction in the terrestrial realm is contentious. The
Beaufort Group is already well known to record the Permo-Triassic Mass Extinction
but it also records an earlier extinction at the top of the Tapinocephalus Assemblage
Zone (AZ). This extinction is very poorly understood but recent radiometric dates
for many Permian assemblage zones of the Beaufort Group have confirmed a Middle
Permian age for Eodicynodon, Tapinocephalus and Pristerognathus assemblage zones and
suggest that the end-Tapinocephalus AZ extinction may coincide with the marine
extinctions.
A recently produced GIS database that accommodates all Beaufort Group fossil
material curated in South Africa formed the basis on which the stratigraphic range of
individual specimens was calculated. To put the fossil localities in a stratigraphic
context, lithostratigraphic information was retrieved from the literature and extensive
fieldwork was conducted, which measured stratigraphic sections in key areas and
traced the surface outcrop of lithostratigraphic units. In order to compensate for
lateral variations in lithostratigraphy, the basin was split into sectors, each
represented by a stratigraphic section. The stratigraphic ranges of fossil specimens
and, subsequently, of genera and families could then be calculated and a workable
biostratigraphic subdivision of the Middle Permian Beaufort Group proposed.
The Abrahamskraal Formation, which forms the majority of the Middle Permian
Beaufort sequence, can be divided into six lithostratigraphic members based on the
occurrence of sandstone ‘packages’. These members were traced laterally across the
Basin and their correspondence with fining-upwards cycles was refined and
correlated with the newly defined biostratigraphic units. This refined two-pronged
stratigraphic subdivision allowed the recognition of a waning period of subsidence in
the proximal sector of the Karoo Basin during the Middle Permian.
Stratigraphic ranges of individual genera were found to be far more heterogeneous
than previously recognised. Dicynodont genera are useful biostratigraphic indicators
due to their relative abundance and well-defined stratigraphic ranges, while
dinocephalians and pareiasaurs are clustered in the upper part of the Abrahamskraal
Formation. The stratigraphic range of Eodicynodon extends further up in the
Abrahamskraal Formation than was previously recognised. The Tapinocephalus AZ is
restricted to approximately the upper fifth of the Abrahamskraal Formation and is
characterised by advanced tapinocephalid dinocephalians and the pareiasaur
Bradysaurus. Between these two biozones is a stratigraphic interval dubbed the mid-
Abrahamskraal Formation Transition Zone, where both Eodicynodon and advanced
tapinocephalids coexisted.
A 75 % loss of generic diversity occurred between the upper Tapinocephalus AZ and
the base of the Pristerognathus AZ, which corresponds to a stratigraphic interval
between the mid-Karelskraal Member of the Abrahamskraal Formation and the mid-
Poortjie Member of the Teekloof Formation. Several taxa that survive the end-
Tapinocephalus AZ extinction, and are relatively common in the overlying
Pristerognathus AZ (scylacosaurid therocephalians, the dicynodont genus Eosimops and
the parareptile Eunotosaurus), all became extinct in the upper Poortjie Member at a
time when generic originations are increasing. This suggests a second wave of
extinctions in a similar fashion to that recorded at the Permo-Triassic boundary.
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The later Stone Age in the Southern Cape, South Africa, during the terminal pleistocene/early holocene with a focus on Klipdrift caveRyano, Kokeli Peter 30 January 2015 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, November 2014. / My analysis of the lithics, shellfish and tortoise recovered from layers dating to between 11.8 and 9.7 ka at Klipdrift Cave (KDC), De Hoop Nature Reserve, southern Cape, provides new information on the Oakhurst technocomplex. A re-analysis of a sample of lithic artefacts from Matjes River Rock Shelter (MRS) indicates many technological similarities, but also unexpected differences, highlighting the need for detailed contextualised studies that could reveal the complexity of the Oakhurst Industry.
The lithic artefacts were analysed following a typo-technological approach. The KDC Oakhurst shares many characteristics typical of this technocomplex from the southern Cape, for example in the dominance of quartzite, irregular and unstandardized flakes, the occurrence of irregular cores and typical large side and end scrapers. It differs from most coastal Oakhurst sites in the more intensive exploitation of quartz, and the presence of a morphological blade component, especially in the lowermost layers.
Shellfish remains were identified to species level in terms of minimum number of individuals (MNI) and weight. The two main species are Dinoplax gigas, dominating in the lower part of the sequence, between 11.8 and 11.1 ka and Turbo sarmaticus that is more numerous thereafter. These species provide the highest energy yield in terms of kilojoules, estimated at 667 511 kilojoules for both species combined. The species composition at KDC reflects changing environmental conditions that may relate to the effect of the Younger Dryas event, changing from a sheltered sandy bay to a habitat with more exposed rocks and less sand after 11.1 ka. T. sarmaticus opercula, Cymbula oculus shells and tortoise medio-lateral humeri were measured to investigate whether human predation pressure could have affected their size. Although the sizes of T. sarmaticus opercula show some decrease through time suggesting human predation pressure on these molluscs, there is also a possibility that environmental factors may have affected Turbo growth. The tortoise sizes at KDC, and some other Oakhurst sites, are similar to that of the Middle Stone Age (MSA) but the KDC data are
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inconclusive on whether intensive harvesting had an effect on average tortoise size.
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An exploration of use-wear analysis on Acheulean large cutting tools: the Cave of Hearths' Bed 3 assemblageLambert-Law de Lauriston, Timothy Stephen January 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the
Witwatersrand, in fulfilment of the requirements for the degree of Masters of Science in Archaeology.
Johannesburg, 2015 / Large cutting tools (LCTs) are a stone tool techno-group that appeared ca. 1.76 Ma in Africa and marked the beginning of the Acheulean. The group is conventionally comprised of three tool types called handaxes, cleavers, and picks. The function of LCTs has only been determined through assumptions (e.g., names based on historical antecedents or assigning functional names to morpho-types) or through experimental tasks designed to determine if a particular tool type was efficient for a given task, (e.g., are handaxes conducive to butchery tasks?). To date, no extensive use-wear analysis has been carried out on African Acheulean LCTs. This is the pioneering study. Utilising a multi-stranded approach comprised of experimental archaeology, blind testing and low- power use-wear analysis the functions of a sample of LCTs from The Cave of Hearths were derived.
The Cave of Hearths (CoH) lies in the Makapan Valley in the Limpopo Province of South Africa. Excavations were carried out from 1947 to 1954, and it is these excavations from which this study draws its sample. Thirty-eight handaxes and cleavers from the CoH Bed 3 Acheulean (ca. 0.5 Ma) were submitted to a low-power use-wear analysis. The results showed that a full range of tasks was performed on site including: wood- working, animal and vegetal matter processing, accompanied by digging and a number of other tasks. Corroborated by faunal analysis and an environmental reconstruction, the results suggest that the cave acted as a home camp/ residential base to the hominins that inhabited the area during the Acheulean. Additionally, evidence was found which may indicate that two of the tools were possibly hafted. If this finding is corroborated by future studies it would push back by approximately 150 Ka the earliest date previously published for hafting with Mode 3 tools.
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The underground central deposits of the Sterkfontein Caves, South AfricaStratford, Dominic Justin 21 May 2012 (has links)
Ph.D., Faculty of Science, University of the Witwatersrand, 2011 / Work on Sterkfontein cave deposits has generally focussed on clarifying the life histories of interned hominin remains. Less attention has been paid to the depositional context of the fossils and the specific stratigraphic processes involved in the formation of deposits, and their interaction within the cave system. Also lacking is an understanding of the complex processes influencing the distribution and integrity of the faunal and artefact assemblages. This research applied a broad-spectrum multidisciplinary approach to investigate a previously unexamined area of the caves with a particularly rich depositional history. The underground central deposits represent several infills of important fossil and artefact-bearing sediments. These sediments have accumulated into one of the deepest central areas of the Sterkfontein cave system creating a confluence area with a complex formation history. Three excavations (STK-MH1, STK-MH2 and STK-EC1) uncovered seven deposits. These deposits document a depositional history ranging from the earliest introduction of allogenic sediments (STK-MH1 T4), to the commercial exploitation of the caves through mining and tourism (STK-MH1 T1, STK-MH2). The stratigraphic sequence for the underground central deposits exhibits multiple formation processes including deposition (through numerous processes), erosion, collapse, diagenetic modification, deformation and displacement. The detailed stratigraphic history of these deposits was elucidated utilising sedimentological, fabric, stratigraphic, taphonomic and taxonomic analyses.
As well as deciphering the complex formation history of this important area, this research attempted to identify the influence of cave sedimentation processes on faunal distribution and assemblage integrity. Faunal assemblages are prone to extensive modification caused by sedimentation and re-sedimentation processes mixing and distributing deposits through the caves. Varying sedimentological properties within fossil-bearing sediment gravity flows can cause the destruction of primary context taphonomic evidence, the concentration of fossils
representing multiple stratigraphically distinct facies, and deposit-wide fossil distributions based on element size and shape. In addition to these processes, it was found that different skeletal elements change shape in different ways through breakage, thereby changing the specific mobility of the fossils and their potential distribution through the sediment body. Not identifying or not accounting for these post-depositional processes can lead to non-representative sampling, and to the misinterpretation of taphonomic and taxonomic data.
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Architecture for resilience: dialogues with place in the indigenous communities of Kuruman during the Holocene periodMaape, Sechaba January 2016 (has links)
A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, 2016 / Since the latter part of the 20th century to the present, we have seen growing concerns about the potential collapse of socio-ecological systems due to climate change. On the other hand, palaeoenvironmentalists, archaeologists and anthropologists consistently point to evidence of how Homo-sapiens have survived within climate variability underpinned by an embodied/embedded relationship to their environments. Archaeological data shows how indigenous groups such as the Bushman have inhabited landscape features such as caves for longer than 10 000 years and thus survived through periods of climate variability.
Another well researched element of Bushman life is their ritual practices. Given the low supply of livelihood resources within the contexts where such communities have survived, this study hypothesised a possible relationship between Bushman ritual practices and their long-term resilience when faced with variability. Using the Holocene habitation of the Wonderwerk Cave as the main case study, this study explored the relationship between people, place and ritual. Furthermore, the study applied phenomenology as the primary data collection method. The resultant first-person experience guided the researcher in engaging with secondary data from archaeology and ethnography.
The study found that Bushman ritual practices such as trance constituted a critical adaptation tool in response to perpetually variable environments. Through such practices and their related tools such as art, space and myth, such communities managed to sustain a synchronised dialogue with place thus facilitating for ongoing dissolution of maladaptive behaviour. Another key finding is that our inability to change constitutes a key characteristic of our species today as we have been seduced into the trap of our deep psychic longing for existential continuity.
The study argues for an architecture for resilience whose primary role would be to facilitate higher fluidity in our embeddedness to place and allowing for faster and trauma-free transitioning in synchronicity to our changing environments. In conclusion, the study finds that our own contemporary climate change has implications far beyond the techno-scientific understanding which has prevailed so far and is instead calling to be understood as an existential phenomenon to be primarily resolved through relevant/responsive ritual practices to facilitate our own transitioning and continued resilience. / MT2017
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Cranial morphology of embrithosaurus schwarzi (Parareptilia, Pareiasauria) and a taxonomic and stratigraphic reassessment of the South African Middle Permian PareiasaursVan den Brandt, Marc Johan January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Master of Science.
Johannesburg, 2016. / Pareiasaurs were abundant, large, herbivorous parareptiles of the middle and late Permian which had a global distribution. The most basal pareiasaurs are found only in the middle Permian of South Africa, suggesting a Gondwanan origin for the group. Despite their relative abundance, most pareiasaurs are poorly known, especially the large middle Permian South African taxa that went extinct at the end of the Tapinocephalus Assemblage Zone. Historic taxonomic confusion was reduced with studies by Lee (1995, 1997a) that addressed the alpha-taxonomy of all pareiasaurs. He reduced the middle Permian South African pareiasaurs from 11 to four species: Bradysaurus baini, B. seeleyi, Embrithosaurus schwarzi and Nochelesaurus alexanderi. However this revision did not include detailed anatomical descriptions of any of the middle Permian South African Tapinocephalus Assemblage Zone taxa.
The first detailed cranial description of Embrithosaurus schwarzi is presented in this contribution. Within the middle Permian pareiasaurians, Embrithosaurus has unique wide, short and stubby teeth with nine marginal cusps arranged more regularly.
A cranial taxonomic reassessment of all middle Permian pareiasaurs has confirmed the validity of the four taxa identified by Lee and produced updated cranial diagnoses for each species. Diagnostic features noted by Lee and retained include an autapomorphic large distinctive maxillary boss on a strongly buckled or bent maxilla for B. baini, distinctive horizontally flat and pointed bosses on the posterior margin of the quadratojugal for Nochelesaurus and the smallest cheek flanges for B. seeleyi.
Using the updated diagnoses, re-identification of 39 specimens out of 108 studied has produced updated biostratigraphic ranges for the middle Permian species. B. seeleyi is the first to make an appearance, in the middle Koornplaats Member of the Abrahamskraal Formation. B. baini first appears in the upper iii
Koornplaats Member, Nochelesaurus in the Swaerskraal Member, and Embrithosaurus in the lower Moordenaars Member of the Abrahamskraal Formation. All taxa disappear by the top of the Karelskraal Member of the Abrahamskraal Formation, confirming that all the middle Permian pareiasaur species went extinct at the end of the Tapinocephalus Assemblage Zone. / MT2017
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The use of faunal evidence to reconstruct site history and Hoedjiespunt 1 (HDP1), Western Cape / The use of faunal evidence to reconstruct site history and Hoedjiespunt 1 (HDP1), Western CapeStynder, Deano Duane, Stynder, Deano Duane 13 December 2016 (has links)
Hoedjiespunt 1 (HDP 1 ), is one of few later Middle Pleistocene to earlier Late Pleistocene African sites to yield well provenanced MSA hominid fossils, lending special significance to this site. The vertebrate fauna from this location, which consists of a palaeontological and an archaeological site, is described and analysed using both the taphonomic and controlled comparison approaches. The information obtained via this study allows for a better understanding of the context in which and the conditions under which these two sites were formed. Stratigraphic evidence and spatial information, suggest that the bones in the palaeontological site were in all likelihood accumulated in a cavity, thus postdating the sediments in which they occur. Circumstantial evidence, in addition to Klein and Cruz-Uribe's (1984) criteria for distinguishing assemblages accumulated by hyaenas from those accumulated by people, points towards the brown hyaena as the most likely accumulator of this assemblage. It is also suspected that the bone in the archaeological assemblage, may postdate the sediments in which they occur. This is suggested by the presence at the site, of tools manufactured out of calcrete, similar to the calcrete carapace which caps the stratigraphic sequence. Although density mediated destruction seems to have been the major cause of discrepancies in skeletal part abundance in the palaeontological site, it was found not to have been severe. The composition of species represented in the two assemblages differ. It was found that, apart from containing a small percentage of marine animals, the palaeontological site is dominated by grazing ungulates and carnivores. This assemblage was accumulated during a period of lowered sea level, or "glacial". On the other hand, the sample from the archaeological site contains proportionally fewer ungulates and carnivores, more small animals and more marine animals, reflecting a period of marine transgression, or "interglacial".
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The exploitation of fish during the Holocene in the South-Western Cape, South AfricaPoggenpoel, Cedric Alan January 1996 (has links)
Bibliography: pages 202-225. / This thesis describes the fish remains recovered from a number of sites in three different localities in South Africa; Elands Bay and Langebaan Lagoon on the west coast, and False Bay on the Cape Peninsula. Chapter One is an introductory account of ichthyology, its usefulness in archaeological research and the range of analytical work done in South Africa, whilst Chapter Two is an attempt to show the history and development of the study of fish bones recovered from prehistoric sites in South Africa. Chapter Three gives an account of the southern Oceans, the Benguela Current and fishing habitats. Chapters Four and Five give accounts of the fishing habitats within the Elands Bay area and of the identification and interpretation of fish assemblages excavated at four sites and their implications in relation to habitat and palaeoenvironmental changes at Elands Bay. This information is used first to show that the presence or absence of certain species and the size of those species in the archaeological record can be used as an alternative means to interpret late Pleistocene and Holocene sea level fluctuations and to understand to what extent local fishing habitats have been influenced by those changes. An important observation made was the relative surplus or deficit of vertebrae compared to cranial parts through the sequence. The over-representation or under-representation of fish vertebrae in the fish assemblages points to changes in the procurement strategy employed. The consistency between cranial:vertebral ratios through the site sequences suggests that these patterns are related to both location and processing techniques. Chapter Six reviews the ecology of the Langebaan Lagoon, the identification of fish assemblages from three open midden stations; Stotbergfontein on the shores of the lagoon and Paternoster and Duiker Eiland which are located on the Vredenberg peninsula. Chapter Seven gives a short overview of the modern fishing situation at False Bay and discusses the fish assemblages from Smitswinkelbaai Cave and Rooiels Cave in the False Bay area. Chapter Eight deals with the archaeological evidence for fishing equipment and the depiction of fishing scenes in the rock art of South Africa and addresses the historical evidence for indigenous fishing in the south-western Cape. Chapter Nine gives an overview of the historical fishing at the Cape, the use of outposts near Langebaan Lagoon and Muizenberg in False Bay by the Dutch to supply the Cape settlement with provisions. In Chapter Ten the relevant evidence from each of the chapters is summarised and the conclusions for the three areas are presented.
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Contributions to knowledge of some Southern African fossil sites and their fossilsVan Dijk, D. E. 03 1900 (has links)
Thesis (MSc (Botany and Zoology. Palaeontology))--University of Stellenbosch, 2001. / The fossil sites and fossils reported here range from the Archaean to the Recent.
Information is presented on the circumstances of the discovery of some fossil sites in
Southern Africa. A number of fossil sites, some of which can no longer be studied,
are photographically recorded. Some recorded sites were relocated, while failure to
locate others is noted. The assemblages at selected fossil sites are compiled,
including some additions to their floras and faunas. Certain individual fossils are
illustrated and discussed. Techniques which are not standard are outlined.
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