A study of the Abrahamskraal Formation in the area around Merweville, in the southwestern corner of the Karoo Basin has revealed the presence of traceable lithological units with lateral continuity throughout the study area. The stratigraphic section measured in this part of the basin matches the section measured by Jordaan, (1990) south of Leeu Gamka, with a basal arenaceous unit overlain by a predominantly argillaceous succession. The thickness of the Abrahamskraal Formation in this part of the Karoo Basin in 2565m, charactersized by a braided depositional environment in the lower 2075m and a meandering depositional environment in the upper 490m. Biostratigraphically the succession comprises a basal Eodicynodon Assemblage Zone which constitutes the lower 1104m and this is overlain by a 1461m thick Tapinocephalus Assemblage Zone whose upper limit is 21m below the Poortjie Member of the Teekloof Formation. This study has also corroborated the work by earlier authors who proposed a northeasterly palaeoflow direction as well as contributing to the global correlation of the Middle Permian terrestrial tetrapod faunas where the Eodicynodon Assemblage Zone correlates with the fauna from the Russian Ocher & Ischeevo; fauna of China’s Xidagou Formation and Rio da Rosto fauna of Brazil while the Tapinocephalus Assemblage Zone fauna corrletaes with fauna from Mezen and Ischeevo in Russia, Posto Queimado fauna in Brazil and those from the Madumabisa strata of Zimbabwe.

No description available.

A significant amount of palynological work has been done on southern African coal seams in the Ecca Group, but as yet there is little consensus on how these areas relate to each other. This study investigated the palynology of a coal seam from Mmamantswe (Mmamabula area), Botswana, approximately 70 km north-east of Gaborone. A total of 124 samples were taken from two borehole cores and subjected to acid preparation, oxidation and acetolysis. Coal samples were found to be barren of palynomorphs. Fifty carbonaceous mudstones and siltstone samples yielded twenty-two productive samples. A thermal alteration index of 3.0-3.5 was assigned for the sediments. Palynomorph diversity was high, with 64 genera and 90 species present, dominated by trilete and alete spores. This indicates a parent flora of mostly lower order lycopods, sphenophytes and ferns. Non-taeniate bisaccate and monosaccate pollens were scarce, and striates extremely rare (only two species), suggesting an autochthonous origin for the coal swamp. The Mmamantswe core was sub-divided into five microfloral assemblage zones. A transition from monosaccate dominance in the lower part of the core, to equal numbers of monosaccates and non-taeniate bisaccates in the upper part of the core, was seen. As the Mmamantswe palynoflora possesses elements of both the Late Carboniferous glacial floras and the mid-Permian coal floras, it is thought to represent a cross-over assemblage dating to soon after the Permo-Carboniferous boundary (Sakmarian and Early Artinskian). The Mmamantswe assemblage can be correlated with Assemblage Zones II and III of Falcon (1975a); Biozones B and C of MacRae (1988); and Zones 1, 2 and 3 of Anderson (1977) but does not fit well into any existing biozonation. The Mmamantswe palynoflora was most similar to that of Milorgfjella, Dronning Maud Land, Antarctica (Larrson et al. 1990) and the No. 2 Seam, Witbank, South Africa (Falcon 1989). Taphonomic controls on palynomorph preservation suggest that future studies should also attempt to focus on Permian sediments not containing coal, as microfloral assemblages from coal seams tend to be autochthonous, and subject to local climatic influences. Accordingly they are not as useful for inter-basinal correlation across Gondwana.

Dissertation (DPhil)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

Thesis (M.Sc.)--Memorial University of Newfoundland, 1996. / Typescript. Bibliography: leaves 136-146. Also available online.

Thesis (doctoral)--Universität zu Köln, 1983. / Three folded maps in pocket. Includes bibliographical references (p. 197-217).

Thesis (MA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The succulent thicket plant community of South Africa, particularly Portulacaria afra (in this study referred to as spekboom), occurring in the Thicket Biome, sequestrates an exceptional amount of carbon dioxide (due to its photosynthetic properties), particularly for a warm, semi-arid region and in this capacity is more akin to forest ecosystems. Spekboom has additional favourable characteristics over forested systems regarding carbon trading (CT), namely: economic water use; potential for combating desertification and poverty in arid environments; and ability to withstand stand-replacing fire (spekboom doesn’t burn) which improves its attraction as a commodity in CT and the payments for ecosystem services (PES) industry. Landowners interested in using the capacity of their land for carbon sequestration (CS) are challenged to calculate their plant communities’ sequestration ability and biodiversity potential and therefore to quantify the carbon credits to be sold. The aim of the study was to quantify the CS ability of a selected property unit by vegetation area and to establish the carbon credits value that can be sold in the carbon market. It commenced by highlighting the problem of global warming and its effect on climate change in South Africa. CS is described as a process and a solution to decrease high and rising atmospheric CO2 levels, and its use in the carbon market to attain a monetary value to promote the growing of vegetation or to protect and conserve biodiversity that will enhance carbon stocks. The study site is Bosch Luys Kloof Private Nature Reserve (BLK PNR) in the semi-arid Karoo. Because CS potential is known to follow a rainfall gradient, one expects the semi-arid Karoo to have a low CS potential. However, this area contains spekboom, an extraordinary thicket type that sequestrates carbon at similar rates to forest ecosystems and should therefore reap the benefits of CT. Yet, accurate mapping of this vegetation is critical for accurate carbon stocks assessment. The CS potential of all vegetation communities in the study area had to be established to estimate the carbon stocks in the whole property unit. ArcGIS was used to map the vegetation communities (sub biomes) and eCognition to refine mapping of the Gamka Thicket (containing spekboom) through an object-orientated approach to automated vegetation mapping. For accuracy assessment a heads-up digitized map was created for comparison. The true surface area was calculated for the vegetation classification to ensure accurate area accounting on the mountainous terrain and this calculated area of the mapped vegetation was used to convert area to carbon sequestration potential. By examining the different markets and trading mechanisms for trading in the carbon market, using CS, a marketing strategy for the land units was advised. Results show that due to BLK PNR's history of overstocking, spekboom remains degraded on the study site. This creates an opportunity to restore the vegetation with funding through CT. The sequestration potential of spekboom on BLK PNR was determined through a regional differentiation comparison. The regional differentiation comparison identified that rainfall amount and carbon accumulation are inversely proportional, therefore more arid conditions (<200mm a year, or a dry season longer than seven and a half months) cause spekboom to switch to Crassulacean acid metabolism (CAM) due to water stress, so increasing the rate of carbon accumulation. In wetter environments, where spekboom is not under water stress, it continues in carbon fixation of 3-phosphoglycerate (C3) having a lower carbon accumulation. This is a remarkable finding as CS is known to follow a rainfall gradient: in this instance spekboom is an exception to the norm. Mapped results showed that eCognition classified spekboom poorly, yielding between 64% and 69% correspondence to the accurate manually classified map. As expected three-dimensional area comparative results show that the true surface area on complex terrains was 10% higher than the original (and surveyed) land area of the estate. Results indicate that there are substantial carbon stocks for CT on BLK PNR. This study recommended the most practised form of CT (restoration) for BLK PNR. Over a period of 30 years of restoration on BLK PNR about 46 000 tons of carbon could be sequestrated. At the current price of carbon credits this could accumulate over R3.7 million over the 30-year restoration period. Combining restoration with conservation strategies into one project type has additional favourable characteristics as it takes into account the CS potential of all vegetation communities on the land unit and the ecosystem services it promotes. Conservation of BLK PNR would yield 758 000 tons of carbon. Calculated through emission abandonment, this could be valued at R8-10 million. The economic importance of the vegetation community’s biodiversity on BLK PNR and significant differences between biomes were recorded and implies a total intrinsic value in excess of R830 000 per annum. To date, pilot projects elsewhere have successfully acquired carbon credits for avoided deforestation through the climate, community and biodiversity alliance (CCBA). However, owing to the pilot stage status there is little literature that substantiates the calculation of the monetary value of conservation. This is a fertile area for further research. / AFRIKAANSE OPSOMMING: Die sukkulent-struikplantgemeenskap van Suid-Afrika, in besonder Portulacaria afra (waarna in hierdie studie as Spekboom verwys word), wat in die Struikgewasbioom voorkom, neem ‘n uitsonderlike hoeveelheid koolstofdioksied op (weens die fotosintetiese eienskappe daarvan), veral vir ‘n warm, semi-ariede streek en is in hierdie kapasiteit meer verwant aan woud-ekosisteme. Spekboom het, met betrekking tot koolstofuitruiling (KU) of koolstofhandel, addisionele gunstige eienskappe bo dié van woudsisteme, naamlik lae waterbenutting; potensiaal vir die bestryding van woestynvorming en armoede in ariede omgewings; en die vermoë om brand te weerstaan (Spekboom brand nie), wat sy aantreklikheid as ‘n kommoditeit in KU verhoog, en die betaling vir dienste in die ekosisteem-industrie (BED) verbeter. Grondeienaars wat geïnteresseerd is in die benutting van hul grond vir koolstofopname (KO), word uitgedaag om hul plantgemeenskappe se opnamevermoë en potensiaal vir biodiversiteit te bereken, en gevolglik die hoeveelheid koolstofkrediete wat verkoop kan word, te kwantifiseer. Die doel van die studie was om die KO-vermoë van ‘n geselekteerde eiendomseenheid volgens die oppervlakte onder plantegroei te kwantifiseer en om die waarde van koolstofkrediete wat in die koolstofmark verkoop kan word, vas te stel. Ten aanvang is die probleem van aardverwarming en die uitwerking daarvan op klimaatsverandering in Suid-Afrika uitgelig. KO word beskryf as ‘n proses en oplossing om die hoë en stygende atmosferiese CO2-vlakke te verminder, en die gebruik daarvan in die koolstofmark, om ‘n monetêre waarde te verkry om plantbedekking te bevorder of om biodiversiteit, wat koolstofvoorraad sal vermeerder, te beskerm en te bewaar. Die studieperseel is Bosch Luys Kloof Privaat Natuurreservaat (BLK PNR) in die semi-ariede Karoo. Omrede KO-potensiaal bekend is daarvoor om ‘n reënvalgradiënt te volg, verwag mens dat die semi-ariede Karoo ‘n lae KO-potensiaal sal hê. Hierdie gebied bevat egter Spekboom, ‘n buitengewone struiksoort wat koolstof teen soortgelyke tempo’s as woud-ekosisteme opneem, en behoort daarom voordeel uit KU te trek. Akkurate kartering van hierdie plantegroei is kritiek vir akkurate assessering van koolstofvoorraad. Die KO-potensiaal van alle plantgemeenskappe in die studiegebied is derhalwe vasgestel om die koolstofvoorrade in die totale eiendomseenheid te skat. ArcGIS is gebruik om die plantgemeenskappe (sub-biome) te karteer en eCognition is gebruik om die kartering van die Gamkaruigte (wat Spekboom bevat) deur ‘n objek-georiënteerde benadering tot geoutomatiseerde plantegroeikartering te verfyn. Vir akkuraatheidsassessering is ‘n vergelykbare plantegroeikaart per hand versyfer. Die werklike oppervlakte van die gebied is vir die plantegroeiklassifikasie bereken om akkurate oppervlakberekening van die bergagtige terrein te verseker, en hierdie berekende oppervlakte van die gekarteerde plantegroei is gebruik om oppervlakte na koolstofopname-potensiaal te herlei. Advies oor ‘n bemarkingstrategie vir die grondeenhede is gegee, deur die verskillende markte en uitruilings- of handelsmeganismes vir handel in die koolstofmark te ondersoek. Resultate toon dat weens die BLK PNR se geskiedenis van oorbeweiding, Spekboom op die studieperseel gedegradeer het. Dit skep ‘n geleentheid om die plantegroei met befondsing deur KU te herstel. Die opname-potensiaal van Spekboom op BLK PNR is deur ‘n streeksdifferensiasie-vergelyking bepaal. Die streeksdifferensiasie-vergelyking toon dat hoeveelheid reënval en koolstofakkumulasie omgekeerd eweredig of proporsioneel is, en gevolglik veroorsaak meer ariede omstandighede (<200 mm/jaar, of ‘n droë seisoen van langer as sewe en ‘n half maande) dat Spekboom weens waterstres na Crassulacea-suurmetabolisme (CSM) oorskakel, en sodoende die tempo van koolstofakkumulasie verhoog. In natter omgewings, waar Spekboom nie aan waterstres onderwerp word nie, gaan dit voort met koolstofbinding van 3-fosfogliseraat (C3) en het ‘n laer koolstofakkumulasie. Dit is ‘n merkwaardige bevinding aangesien KO daarvoor bekend is dat dit ‘n reënvalgradiënt volg: in hierdie geval is Spekboom ‘n uitsondering op die reël. eCognition het Spekboom swak onderskei, en slegs ‘n ooreenstemming van tussen 64% en 69% met die akkurate hand-geklassifiseerde gehad. Soos verwag, toon vergelykende resultate van driedimensionele oppervlakte dat die werklike oppervlakte byna 10% hoër is as die oorspronklike (en gemete) grondoppervlak van die eiendom. Resultate dui aan dat daar aansienlike koolstofvoorrade vir KU op BLK PNR is. Hierdie studie beveel die mees gebruikte praktyke van KU (herstelproses) vir BLK PNR aan. Oor ‘n hersteltydperk van 30 jaar op BLK PNR kan ongeveer 46 000 ton koolstof opgeneem word. Teen die huidige prys van koolstofkrediete kan dit meer as R3.7 miljoen oor die hersteltydperk van 30 jaar akkumuleer. Die kombinasie van herstelprosesse en bewaringstrategieë in een tipe projek, hou addisionele voordeel in, omdat dit die KO-potensiaal van alle plantgemeenskappe op die grondeenheid en die ekosisteem-dienste in berekening bring. Bewaring van BLK PNR sal 757 913 ton koolstof lewer. As dit in terme van die staking van uitlatings bereken word, kan dit teen R8-10 miljoen gewaardeer word. Die ekonomiese belangrikheid van die ekosisteem en plantgemeenskap-biodiversiteit op BLK PNR impliseer ‘n totale intrinsieke waarde van meer as R800 000 per jaar. Loodsprojekte elders was suksesvol in die verkryging van koolstofkrediete vir die vermyding van ontbossing deur die klimaat-, gemeenskap- en biodiversiteitsalliansie (KGBA). Vanweë die loodsprojekstatus, is daar egter min literatuur beskikbaar wat die berekening van die monetêre waarde van bewaring staaf. Dit laat ruimte vir verdere navorsing.

Magister Scientiae - MSc / The prospect of unconventional shale-gas development in the Karoo Basin (South Africa) has created the need to obtain baseline data on natural radioactivity in Karoo groundwaters. The Karoo Basin groundwater radiological baseline developed through this study could serve as a reference to research potential future radiological contamination effects due to hydraulic fracturing. The major naturally occurring radioactive material (NORM) studied was radon (222Rn), in particular in-water activity concentrations; however, supplementary radium (226Ra and 228Ra) in-water activity concentrations and uranium (238U) in-water concentrations measurements were also made. A total of 53 aquifers across three provinces were sampled for groundwater and measured, with three measurement series from 2014 to 2016. The aquifers were categorized as shallow, mixed, or deep source. The radon-in-water baseline of the Karoo Basin can be characterised by a minimum of 0.6 ± 0.9 Bq/L, a maximum of 183 ± 18 Bq/L and mean of 41 ± 5 Bq/L. The radon-in-water levels from shallow sources (with water temperature < 20 °C) were systematically higher (40 Bq/L) than for deep sources (with water temperature > 20 °C). The natural fluctuations in radon-in-water levels were predominantly associated with shallow aquifers compared to almost none observed in the deep sources. The uranium in-water baseline can be characterised by a minimum of below detection level, a maximum of 41 μg/L, and the mean of 5.10 ± 0.80 μg/L. Similar to radon-in-water levels, uranium in-water levels for shallow sources were systematically higher than for deep sources. The limited (six aquifers) radium (228Ra and 226Ra) in-water activity-concentration measurement results were very low, with a maximum of 0.008 Bq/L (226Ra) and 0.015 Bq/L (228Ra). The 228Ra/226Ra ratio baseline were characterised by a minimum of 0.93, a mean of 3.3 ± 1.3, and a maximum of 6.5. The radium isotopes’ activity concentration ratio is an isotopic tracer for hydraulic fracturing wastewater. Pollution and contamination (radiological), due to unconventional shale gas development, in water resources has been noticed in the Marcellus Basin (United States). Consequently, developing and improving continuous baseline monitoring are of importance to study the environmental radiological effect of hydraulic fracturing.

>Magister Scientiae - MSc / The present research deals with the characterization of the Lower Ecca Group in terms of sedimentology, mineralogy and organic geochemistry. A field study was conducted in order to characterize the sedimentology and thereby determine the environments of deposition of the Prince Albert, Whitehill and Collingham Formations. In addition, shale samples were subjected to geochemical and mineralogical analyses so as to ascertain its source rock properties. The study utilized X-ray diffraction (XRD), scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), total organic carbon (TOC) and Rock-Eval pyrolysis to determine the mineralogy and organic geochemistry of shale from the formations under investigation. The sedimentological investigation revealed that the upper Prince Albert Formation is dominated by shale with thin beds of carbonate. These shales are interpreted to have been deposited by suspension settling in a marine environment which was occasionally interrupted by deposition of carbonates that form in a shallow marine environment. The overlying Whitehill Formation consists predominantly of carbonaceous shale with relatively more resistant shale beds also present. The fine sediments are interpreted to have been deposited from suspension settling under anoxic bottom conditions which would favor the preservation of organic rich material. Deposition of the Whitehill Formation was followed by the Collingham Formation which is dominated by rhythmic deposits of shale and sandstone that are occasionally interrupted by tuff layers. The clay size sediments are interpreted to have been deposited from suspension settling which are interbedded with low density turbidite current deposits in a marine environment. Based on the findings of the field study, it is apparent that the Prince Albert and Collingham Formations were deposited in marine environments, with the Whitehill Formation being deposited in an anoxic environment. These environments are known to be dominated by phytoplanktonic organisms and algal debris, and as such shales deposited in these environments contain predominantly Type I (derived from algae) and II kerogen (derived from plankton). It can therefore be postulated that Type I and II kerogens are the dominant constituents of organic matter in the Lower Ecca Group shales. Mineralogically, the shales consist chiefly of kaolinite, smectite and illite clay minerals, which are derived from a combination of weathering of feldspars, and the alteration of other clay minerals. The latter being inferred from the existence of albite in all the studied shale samples, pyroclastic material observed in the field, as well as the occurrence of alteration along clay mineral edges.

The primary aim of this study was to determine who claims the corbelled buildings in the Karoo as their heritage and why. Through the use of vernacular architecture and heritage identification theory, interviews and research it is clear that the buildings are significant and a heritage resource. Their significance lies in their historical, social, aesthetic, symbolic and cultural values, as well as their unique vernacular construction and limited distribution. The corbelled buildings as vernacular buildings are part of the natural landscape which the local community associate as part of their identity and heritage. The buildings also possess academic and historical potential as they have the potential through further archaeological and vernacular architectural research, to provide more information on the northern frontier during the late 18th and early 19th centuries, a time that is not well recorded or documented. The buildings were built in 19th century along the ‘open’ northern frontier where there was intermingling and creolisation of people from different economic and social groups. As a result, they cannot be claimed by a single group of people in the present. The vast range in types and styles of corbelled buildings indicate that they were built by most people living in the area. They can therefore, be claimed by everyone who lives in the area today. They can also be claimed as national heritage as they possess values that are common to the whole country.