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The hydrogeology and hydrogeochemisty of the aquifers of the Hex River Valley, Cape Province

- Rosewarne, Peter Nigel

  • Authors: Rosewarne, Peter Nigel
  • Date: 1984 , 2013-04-11
  • Subjects: Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4863 , http://hdl.handle.net/10962/d1007224 , Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
  • Description: The Hex River Valley is one of the main centres in South Africa for cultivation of table grapes of export quality. The vines require irrigation water, which must be low in dissolved solids. Approximately two thirds of the annual irrigation requirement is obtained from boreholes and the balance from surface water sources. During the early 1960s a deterioration in the quality of the groundwater was noticed, becoming critical in some areas, and borehole yields also declined. The main objectives of this study were therefore to obtain an understanding of the hydrogeological and hydrogeochemical processes operating in the valley to explain the derogation of the groundwater resource and enable optimum utilisation and management of the resource in the future. To achieve these objectives, field work involving exploration drilling, aquifer tests, hydrocensus, long-term monitoring of groundwater levels and surfacewater flows and extensive sampling of the ground and surface waters was carried out. Analysis of these data gave quantitative information on groundwater occurrence, aquifer hydraulic properties, groundwater recharge and storage, chemical characteristics of the ground and surfacewaters and sources of dissolved species. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 1984

The Karoo igneous province: an introduction

- Eales, Hugh V, Marsh, Julian S, Cox, K G

  • Authors: Eales, Hugh V , Marsh, Julian S , Cox, K G
  • Date: 1984
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/133945 , vital:37043 , http://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetailamp;idt=6519910
  • Description: The Karoo rocks are amongst the earliest manifestations of igneous activity accompanying the break-up of Gondwanaland during the early Mesozoic. Remnants of the once extensive lava sequence and the associated dolerite sills are found throughout southern Africa south of latitude 150S, the present outcrop being ca. 140,000 km². The main peak of volcanic activity is dated at about 190 m.y. and is probably coincident with the earliest stages of the opening of the Indian Ocean by the separation of Antarctica from southern Africa.
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  • Date Issued: 1984

The Lord is my Shepard

- Nowotay, N., Doctor, Mixed Church Choir and Queenstown Cathedral Congregation, Composer Not Specified, Dargie, Dave, Huwiler, Kurt

The Lord is my Shepard

- Church Congregation, Composer not specified, Dargie, Dave, Huwiler, Kurt

The Lord's my Shepherd, I'll not want

- Queenstown Roman Catholic Cathedral ordination choir of 1984, Composer not specified, Dargie, Dave

The mathematical experience : inaugural lecture delivered at Rhodes University

- Kotze, W.J.

  • Authors: Kotze, W.J.
  • Date: 1984
  • Language: English
  • Type: Text
  • Identifier: vital:644 , http://hdl.handle.net/10962/d1020713 , ISBN 0868101060
  • Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1984

The petrology of the Merensky cyclic unit and associated rocks and their significance in the evolution of the Western Bushveld Complex

- Kruger, Floris Johan

  • Authors: Kruger, Floris Johan
  • Date: 1984
  • Subjects: Petrology -- Africa, Southern Petrofabric analysis
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5006 , http://hdl.handle.net/10962/d1005636
  • Description: A brief review of the various models proposed to account for the Bushveld Complex shows that there are two main hypotheses. These are the Multiple Intrusion hypothesis and the In Situ Crystallization hypothesis. The latter also allows for multiple additions to the crystallizing magma, and several variants involving the number of these inputs , their composition, volume and timing have been proposed. To facilitate description and investigation of the study section, the stratigraphic nomenclature of this part of the Rustenberg Layered Suite is revised and clarified. It is proposed that the boundary between the Critical Zone and Main Zone be placed at the base of the Merensky cyclic unit, and thus the whole of the Merensky and Bastard cyclic units are included in the Main Zone. Furthermore, the extremely confused terminology for smaller units within the Merensky and Bastard cyclic units is resolved by discarding the term Reef as a formal term and substituting lithological terms such as Merensky pegmatoid, Merensky pyroxenite, Bastard pyroxenite and Merensky mottled anorthosite etc. It is recommended that the term Reef be retained as an informal term to designate the mineralized horizon which may be mined, regardless of lithology. The term "pegmatoid" is restricted to stratiform or lensoid masses of coarse grained feldspathic pyroxenite or harzburgite which are part of the layered sequence. The transgressive vertical pipe-like, coarse-grained ultramafic "iron-rich bodies are termed "ultramafic pegmatites ". The main features of the Merensky and Bastard cyclic units are the regular chemical and mineralogical changes that occur with respect to stratigraphic height in these units. In the Merensky cyclic unit there is a smooth iron enrichment in the orthopyroxenes upward in the succession and a transition from pyroxenite at the base to mottled anorthosite at the top of the unit. The Bastard cyclic unit is broadly similar to the Merensky cyclic unit. A variety of textures and chemical features are in disequilibrium in some samples but not in others, and great complexity is evident wh en individual samples are studied in detail. The initial ⁸⁷Sr/⁸⁶Sr ratios of plagioclase separates and whole rocks from the study section show a distinct step-like increase in the Merensky cyclic unit to .70806 at the base of the, Merensky cyclic unit to .70806 at the base of the Bastard cyclic unit. In contrast , samples from below the Merensky cyclic unit have a constant initial Sr-isotopic ratio, as do the samples from the Bastard cyclic unit. These isotopic and chemical data, and available published geologic relationships suggest that a major new influx of basic magma occurred after the Footwall unit was deposited and that this mixed with the residual magma in the chamber and then precipitated the Merensky and Bastard cyclic units. The crystal settling theory as outlined by Wager and Brown (1968) fails to account for the chemical and stratigraphic variations observed in the study section. The theory of bottom crystallization, initially proposed by Jackson (1961), more adequately explains the features observed. Applying a model outlined by Irvine (1980a & b), it has been established from chemical data, that the Merensky cyclic unit crystallized from a magma layer with a thickness roughly equivalent to the average thickness of the cyclic unit itself (±10m). A similar exercise on the Bastard unit was not possible. The formation of the Footwall unit is still enigmatic. Infiltration metasomatism and sintering can modify the petrographic and chemical characteristics of rocks and minerals after deposition at the liquidus stage. During the solidification of the crystal mush a separate vapour phase may form in the crystal mush, which could move up through the crystal pile. This process may ultimately be responsible for the generation of potholes and pegmatoidal horizons, such as the Merensky pegmatoid. The upward increase in the initial ⁸⁷Sr/⁸⁶Sr ratio within the Merensky cyclic unit is strong evidence that infiltration metasomatism has played an important part in the generation of the Merensky cyclic unit. This process, coupled with fluid enrichment, may also result in the formation of pegmatoid layers. Sintering appears to have been a common process in the mottled anorthosites of the study section and may have severely reduced the amount of trapped interstitial liquid in these rocks.
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  • Date Issued: 1984

The population dynamics of the rock hyrax procavia capensis (Pallas, 1766) in the Mountain Zebra National Park

- Fourie, Leon Johan

  • Authors: Fourie, Leon Johan
  • Date: 1984
  • Subjects: Rock hyrax Mountain Zebra National Park (South Africa)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5743 , http://hdl.handle.net/10962/d1005429
  • Description: The chief objective of the study was to investigate the population dynamics of the hyrax in the Mountain Zebra National Park (MZNP). To realise this objective information on growth, age determination, reproduction, habitat utilization, behaviour, parasites and mortality had to be gathered. The growth of hyrax in relation to age is described by means of Stevens asymptotic regression equations. Near asymptotic measurements are attained first in hind foot length (at 30-33 months of age), head/body length (at 37-39 months of age), girth (at 41-48 months of age) and body mass (at 68-70 months of age). Allometric growth of the various body measurements was investigated and useful predictive relationships for mass are presented. Age determination of hyrax was studied in detail. Cementum annuli counts provided reliable estimates of age. One primary cementum line is formed annually. The dried eye lens mass was an accurate means of age determination up to c. 72 months of age. A summary of findings which will facilitate age determination of dead animals or skulls, and live animals, is provided. Reproduction in the hyrax was studied with emphasis on breeding season, age-specific litter sizes, prenatal mortality and lactation. Male hyrax attained puberty at 15-17 months of age or one year later. Females generally attained puberty at 15-17 months of age. One female (1,4% of total shot sample for the specific age group) attained puberty at 4-5 months of age. Middle-aged hyrax had significantly larger litter sizes than younger animals. Hyrax in the MZNP feed on at least 80 different plant species belonging to 33 plant families. Crude protein of stomach contents and faecal samples showed little seasonal fluctuation implying that hyrax in the MZNP were on a stable quality diet. Female hyrax enjoyed a significantly better quality diet than males for the four month period prior to parturition and during the first two months of lactation. The crude protein values of faecal and stomach samples had a significant correlation. Body fat of male and female hyrax showed seasonal variation related to physiologically stressful periods. Seasonal differences in activity patterns were demonstrated. The basic structure of hyrax social organization is the multi-female kinship group that is matrilocal. Territorial dominant males maintain harems and exclude all other adult males. Peripheral males occupy areas on the periphery of the activity areas of other members of the hyrax colony. Peripheral males do not form bachelor groups and are normally younger than territorial males. It is suggested that territorial males are able to monopolize between 3-17 females in a successful and energetic manner. Both natal and breeding dispersal occurred, the former being considerably more extensive than the latter. The ecto- and endoparasites of hyrax were identified and their burdens quantified over a 13 month period. Juveniles had significantly larger burdens of ectoparasites than did adults. Information on age-specific mortality was obtained from skulls collected in the field and at black eagles' nests. Losses that occurred in the study population due to caracal and black eagle predation were quantified. Evidence is supplied which indicates that juvenile mortality may fluctuate markedly. The population dynamics of the hyrax population in the MZNP was studied by the use of time specific life-tables, models on population growth rates, population simulation models and sensitivity analysis. Sensitivity coefficients were used as a predictor of population regulation. Female juvenile mortality was considered to be the main regulating factor. Changes in fecundity schedule are important compensatory mechanisms and also play an important role in the regulation of a hyrax population. Predation, particularly by caracal, is thought to dampen population fluctuations.
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  • Date Issued: 1984

The practical and theoretical implications of pretreatment and posttreatment anxiety levels in alcoholic in-patients

- Thomson, Peter R S

  • Authors: Thomson, Peter R S
  • Date: 1984
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:21129 , http://hdl.handle.net/10962/6494
  • Description: Pretreatment and posttreatment anxiety scores on the IPAT Anxiety Inventory and the Taylor Manifest Anxiety Scale were obtained from 27 alcoholic in-patients who participated in an alcoholic treatment programme. The treatment programme focused on abstinence and not on anxiety reduction. The results showed that there was a significant decrease between the pre- and the posttreatment anxiety scores on both measures . The duration of hospitalization or the attendance of group psychotherapy did not affect the decrease in anxiety scores. The implications of these results for Pattison's (1979) Multivariate Multimodal model of alcoholism are discussed.
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  • Date Issued: 1984

The role of continental lithosphere in the generation of the Karoo volcanic rocks: evidence from combined Nd-and Sr-isotope studies

- Hawkesworth, C J, Marsh, Julian S, Duncan, Andrew R, Erlank, Anthony J, Norry, M J

  • Authors: Hawkesworth, C J , Marsh, Julian S , Duncan, Andrew R , Erlank, Anthony J , Norry, M J
  • Date: 1984
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/134165 , vital:37080 , https://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetailamp;idt=6453596
  • Description: 143Nd/144Nd, 87Sr/86Sr, Sm and Nd analyses are reported on suites of Karoo volcanic rocks from the four sub-areas of Nuanetsi-north Lebombo, south Lebombo, the Central area, and north-west SWA/Namibia. Only seven (12%) of the samples analysed have positive ENd values similar to those found in the majority of recent mantle-derived rocks. Most of the rest have negative ENd (-1.0 to -17.1) and positive ESr, (+3.0 to +240) and thus must contain at least a contribution from source areas which were both old, and had lower Sm/Nd and higher Rh/Sr ratios than the bulk earth.
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  • Date Issued: 1984

The search for power and legitimacy in Black urban areas: the role of the Urban Councils Association of South Africa

- Atkinson, Doreen

  • Authors: Atkinson, Doreen
  • Date: 1984
  • Subjects: Urban Councils Association of South Africa Neighborhood government -- South Africa Black people -- South Africa -- Politics and government
  • Language: English
  • Type: Book , Text
  • Identifier: http://hdl.handle.net/10962/1864 , vital:20234 , ISBN 0868101141
  • Description: Since their establishment in 1977, Community Councils, like their predecessors, have been severely criticised by urban blacks for their powerlessness. Councillors themselves are disappointed with their inability to improve the living and working conditions of their constituents, and are aware of the rejection of councils as a meaningful political forum by many sectors of black society. In 1978 the Urban Councils Association of South Africa (UCASA) was formed to tie together the ineffective Councils into a more forceful power bloc, which would provide Councils with greater legitimacy and political credibility in the community. By doing so, UCASA acts as a counter to the Administration Boards manned predominantly by whites; UCASA is therefore in the difficult position of operating within government- created structures, while challenging the very structure on which itself is based. This report will outline UCASA's structure and activities within the context of the controversial position of local black urban authorities. It will also be necessary to describe UCASA's political standpoints, both on issues relating to Community Councils and broader South African problems. Three dominant themes constantly recur: structural deficiencies within UCASA itself; tension between UCASA and white officials within Administration Boards and the Department of Co-operation and Development; and UCASA's reaction to left-wing critics who adhere to the non-collaborationist approach with regard to government-created institutions. These divergent attitudes to UCASA will be discussed in more detail towards the end of the paper; finally, an evaluation of UCASA's success in establishing itself as a focal point of pressure for reform from within the ranks of Community Councils will be presented. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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  • Date Issued: 1984

The synthesis and properties of some polymer hydrogels

- Hird, Bryn

  • Authors: Hird, Bryn
  • Date: 1984 , 2013-04-05
  • Subjects: Colloids
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4428 , http://hdl.handle.net/10962/d1006975 , Colloids
  • Description: The interactions between water molecules and polyelectrolyte species in aqueous solutions are reviewed and are used to infer interactions occuring in swollen crosslinked polyelectrolyte hydrogels. Linear poly(acrylic acid ) and derivatives neutralised to varying degrees with alkali-metal hydroxides are prepared and characterised. Samples of these compounds are crosslinked by 'Y - irradiation to form hydrogels. Hydration studies on linear polymers, crosslinked material and a commercial polyacrylate hydrogel indicate a possible hydration structure and provide some insight into the nature of water-polymer interactions within a sHollen polyacrylate gel. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 1984

The winter diet of gentoo penguins at Marion Island

- LaCock, G D, Hecht, Thomas, Klages, N

  • Authors: LaCock, G D , Hecht, Thomas , Klages, N
  • Date: 1984
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/448453 , vital:74731 , https://doi.org/10.1080/00306525.1984.9634486
  • Description: The diet of Gentoo Penguins Pygoscelis papua at Marion Island was studied during September 1982. Samples were obtained from 64 birds using a stomach-pump. Fish accounted for 70% of the diet by wet weight, and crustaceans 30%. Fishes occurred in 72% of the samples, crustaceans in 75%, cephalopods in 13%, and molluscs in 8%. Cephalopods and molluscs did not form a significant proportion of any single sample. Harpagifer georgianus was the predominant fish in the diet (92,7% of otoliths recovered), and Nauticaris marionis was the only crustacean.
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  • Date Issued: 1984

Thuma mina = Send me my Lord

- Ntsikana Memorial Church Congregation, Zwelitsha Independent group of churches, Composer not specified, Dargie, Dave

Title Not Specified

- Dywili, N., Daughter of N. Dywili, Composer Not Specified, Dargie, Dave, Muller, Carol, Jopp, Janet

Title Not Specified

- Xhexhe, Siyabonga, Lelekho, Mbulelo, Composer Not Specified, Dargie, Dave, Muller, Carol, Jopp, Janet

Title Not Specified

- Zola Choir, Marimba players of Jouberton, Composer Not Specified, Dargie, Dave

Title Not Specified

- Dywili, N., Daughter of N. Dywili, Composer Not Specified, Dargie, Dave, Muller, Carol, Jopp, Janet

Title Not Specified

- Zola Choir, Marimba players of Jouberton, Composer Not Specified, Dargie, Dave

Title Not Specified

- Zola Choir, Marimba players of Jouberton, Composer Not Specified, Dargie, Dave

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