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Tatani

- Guardian Angels, Composer not specified, Dargie, Dave

Text and context : an examination of the way in which John's prologue has been interpreted by selected writers : Origen, Luther and Bultmann

- Latham, Jonathan Cyril

  • Authors: Latham, Jonathan Cyril
  • Date: 1988 , 2013-02-28
  • Subjects: Bible -- John -- Criticism, interpretation etc.
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:1225 , http://hdl.handle.net/10962/d1004612 , Bible -- John -- Criticism, interpretation etc.
  • Description: In chapter one of this work, as a preliminary to the formulation of the question that this thesis will attempt to answer, the changing understanding of the part played by the interpreter in the process of interpretation is discussed. This outline begins with the understanding of the role of the interpreter in liberal theology - where he is thought of as one who applies critical methods to the text in a detached and scientific way. After this the hermeneutic spiral is discussed - the formation of this model acknowledges to a greater degree the individual and human part played by the interpreter. This is followed by a brief examination of the most recent theories of interpretation in which meaning is regarded as residing not in the text but in the interpreter himself. The task of this thesis is to determine whether, as these recent theorists suggest, the reader creates meaning instead of reading out what somehow lies in the text itself. The task of this thesis is to ascertain, by studying the interpretationsof John's Prologue by Origen, Luther and Bultmann, whether the text does in fact operate as a series of sign-posts that pOint the interpreter to a destination within his own semantic universe. This may be determined by noting whether or not the contexts, i n the broadest sense, of these interpreters have played a formative part in their interpretations. contextual influences are regarded as existing wherever there is a procedure or meaning in the interpreter's commentary which one expe cts to find there as a result of one's knowledge of the interpreter's life and previous writings. Our research reveals that Orige n, Luther and Bultmann have produced three very different commentaries in which the common denominator is the formative influence of the interpreter's context. Each of these writers has produced an interpretation that is consistent, in both approach and theology, with their previous exegetical and theological thought. This indicates that contextual factors have played a significant part in determining their interpr etations of John 1 :1-18. It would appear that these interpreters have been led to find the meaning of John's Prologue not with reference to any new, unprecedented set of symbols, but with reference to their own, well-worn semantic universes. In the conclusion it is noted that this research appears to support what many modern theorists have said as to the locus of meaning in interpretation. In the conclusion it is also noted that many of the fears raised by these findings - that readers and writers, or speakers and hearers, may become so isolated and trapped in their own thought worlds that any real contact with the outside is impossible - may be groundless. These findings also point to a certain consistency between the interpreters and their communities. This refutes the fears as to the isolation and solitary development of the individual in that it points to a certain community or corporate aspect which plays a part in the development of the indivi dual's semantic universe . , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 1988

Thanda Moya

- Christ the New Man Choir, Composer Not Specified, Dargie, Dave

Thanda moya

- Christ the New Man Choir, Composer not specified, Dargie, Dave

Thanda umelwana wako = Love thy neighbour

- St Peter's Choir, Composer not specified, Dargie, Dave

Thanda umelwane wakho

- St John Vianney Seminary Congregation, Composer not specified, Dargie, Dave, Huwiler, Kurt

Thanda Ummelwane

- Marimba Group, Composer Not Specified, Dargie, Dave

Thanda ummelwane

- St Peter's Choir, Composer Not Specified, Dargie, Dave

Thanda Ummelwane

- Marimba Group, Composer Not Specified, Dargie, Dave

Thandanani Zitlanga Zonke

- St Mary's Workshop Participants, Silangwe, Nosisi, Matsepu, Daniel, Tsoeu, Elizabeth, Dargie, Dave

Thata nazi izipho

- St Joseph's Choir, Composer Not Specified, Dargie, Dave

Thata nazi izipho nkosi

- St Joseph's Choir, Composer not specified, Dargie, Dave

The Albania settlement of Griqualand West, 1866-1878

- Kurtz, June Margaret

  • Authors: Kurtz, June Margaret
  • Date: 1988
  • Subjects: Land settlement -- South Africa -- Cape of Good Hope , Albania (South Africa) , Griqualand West (South Africa) -- History
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2582 , http://hdl.handle.net/10962/d1004665 , Land settlement -- South Africa -- Cape of Good Hope , Albania (South Africa) , Griqualand West (South Africa) -- History
  • Description: The history of the Albania Settlement of Griqualand West is examined from its beginnings in 1866 to its demise in 1878. Albania was very much a product of its time. Nineteenth century British colonial policy was basically expansionist, despite minor fluctuations caused by the various influences affecting it, such as the Free Trade and Mercantilist doctrines, social factors within Britain and events within the colonies themselves. From 1815 colonial settlements were fairly common in British territory, especially after Wakefield had provided a convincing theoretical framework for them. Within South Africa itself there are differing interpretations of what motivated British policy and of the role of the missionaries, while the changing political and economic landscape markedly affected Britain's decisions. British Government settlement schemes were undertaken mainly for social or military reasons, but there were also many settlements founded by land speculators. The economically depressed 1860s hit the Eastern Cape hard and this, combined with the transition to sheep farming, which created considerable land hunger, made the Albania scheme attractive to Eastern Cape farmers. The Griqua people led by Andries Waterboer had made a great effort to establish hegemony north of the Orange River, over the Sotho-Tswana and other Griqua chiefs. By 1866 the attempt had failed and Free State farmers were encroaching onto Nicholas Waterboer's lands. When Waterboer's agent, David Arnot, proposed the establishment of a settlement of Albany men to act as a "Wall of Flesh", Waterboer accepted the idea. Arnot's motivation was also land speculation in an area where diamonds were likely to push up land values. From its inception the settlement was dogged by quarrels, mainly over land, amongst the parties involved - the Griqua, brutally removed to make way for the settlers; the settlers, dissatisfied with the land tenure system and their administration; Arnot; the British and the encroaching Boer farmers . After the 1871 annexation of Griqualand West, into which Albania was absorbed, it took seven years, two Land Commissions, a Land Court and a special Land Claims Commissioner to sort out the tangled claims and bring order to the area and Albania's history to a close.
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  • Date Issued: 1988

The biology of Acia lineatifrons (Naude) (Homoptera : Cicadellidae) on grapevines in the Western Cape

- Marais, Elleunorah

  • Authors: Marais, Elleunorah
  • Date: 1988
  • Subjects: Homoptera
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5597 , http://hdl.handle.net/10962/d1002047
  • Description: The leafhopper, Acia lineatifrons (Naude) was identified as a pest on grapevines near Tulbagh in 1978 and has since been reported on grapevines all over the South Western Cape. A. lineatifrons causes browning of the leaves which often results in the shedding of the discoloured leaves. Heavy defoliation before harvest can result in sunburn damage to the grapes, whilst premature leaf loss after harvest adversely affects the ripening of the canes and the accumulation of reserves. This project was aimed at obtaining basic information on the biology and population dynamics of A. lineatifrons as well as to identify priorities for future research. This information is needed to develop a reliable crop-linked predictive model, methods for monitoring pest populations as well as to develop efficient short- and long-term control measures and pest management strategies. The life cycle of A. lineatifrons was studied in the laboratory. At 26°C the mean incubation period of the eggs was nine to eleven days, the mean developmental period for the five nymphal instars was 15 days and the minimum pre-oviposition period five to ten days. This adds up to a mean generation time of 29 to 36 days at 26°C. At 20°C the mean nymphal development period was 25 days, confirming the strong influence of temperature on the development rate. Fecundity was determined in the laboratory as the number of nymphs produced per female. The mean of 8,5 nymphs per female recorded at 26°C is very low compared to that of other leafhopper species (see Appendix 2). The low fecundity measured was most likely due to sub-optimal environmental conditions in the laboratory, a reduction in the suitability of the host plant under these conditions and handling of the females. The seasonal occurrence of A. lineatifrons on grapevines was studied over three seasons. It was found that the leafhoppers overwinter in the adult stage on indigenous Rubus spp, and that they enter the vineyard from the end of October until the beginning of November. Peak populations occurred between the middle of February and the end of March after which the population declined steadily towards the end of the season as the vine leaves were shed. The sex ratio of the overwintering population on R. chrysocarpus was heavily female biased, possibly due to differential mortality of the sexes. During the growing season the sex ratio was slightly male biased and reached equality on several occasions, both on the Rubus and on the grapevines. The movement of A. lineatifrons between the Rubus and the grapevines was investigated, but no evidence of a directional migration from the Rubus to the grapevines was found. Furthermore, no evidence was found to indicate that morphologically distinct short- and long-distance fliers, as found in Cicadulina species by Rose (1972b), exist in the A. lineatifrons population. Host preference tests also showed that adult leafhoppers apparently have no significant preference for grapevines to Rubus or vice versa. It seems, therefore, that the leafhoppers' move onto the grapevines at the beginning of the growing season is not prompted by a host preference. Chaboussou (1971) suggested that certain organic fungicides may cause leafhopper outbreaks because they affect the suitability of the vines as host plants and alter leafhopper fecundity. The effect of Mikal-M (active ingredient Fosetyl AL/Mancozeb), a systemic dithiocarbanate fungicide, on A. lineatifrons was investigated. Laboratory experiments showed no significant effect on fecundity and leaf analysis of potted vines treated with Mikal-M indicated no significant difference in total leaf nitrogen compared to untreated control plants. However, the field experiment on the effect of Mikal-M on the population build-up of the leafhopper showed that significantly more leafhoppers occurred on the vines treated with Mikal-M than on those treated with a conventional inorganic fungicide, copper oxychloride. In view of the far-reaching implications this can have on the viticultural industry, further research on the effects of organic fungicides on leafhopper populations is recommended to confirm the generality of these results so that recommendations regarding the use of these fungicides may be made. The question as to why A. lineatifrons became a pest only recently was raised. Three possibilities were considered, namely (1) that A. lineatifrons is a species of tropical origin which moved down the continent and became established in the Western Cape only recently, (2) that is has been in the Western Cape at least as long as the grapevines, but required prolonged exposure to establish itself on the new host and (3) that is has been on the vines for some time, but was noticed only recently when outbreaks occurred. These outbreaks could have been caused by the introduction of organic fungicides or the depletion of natural enemies by insecticides used to control other insects in the vineyards. Due to the lack of evidence this question could not be answered conclusively. Other research priorities that were established are the development of methods for damage assessment and monitoring of leafhopper populations, determining if A. lineatifrons can transmit grapevine virusses, the development of an economic threshold level and the identification of natural enemies of A. lineatifrons to enable the development of efficient pest management strategies (Summary, p. 63-65)
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  • Date Issued: 1988

The development of a concept of psychological well-being

- Bar-On, Reuven

  • Authors: Bar-On, Reuven
  • Date: 1988
  • Subjects: Mental health -- Psychological aspects Personality
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2928 , http://hdl.handle.net/10962/d1002437
  • Description: This thesis focuses on the development of an operational and theoretically eclectic concept of psychological well-being. A comprehensive research strategy was employed to examine various personality factors thought to be components of psychological health (i.e., the basis of the proposed concept). The general approach involved four major phases: (1) the clustering of various variables and identification of underlying key factors purported to be related to psychological health based on the writer's clinical experience and review of the mental health literature, (2) the formulation of an ~ priori concept of psychological well-being based on the operational definition of those factors, (3) the construction of an inventory designed to examine the proposed concept, and (4) the interpretation of the results and their implications for the development of the overall concept based on the examination of the factorial structure, validity and reliability of the inventory. The"a posteriori concept" evolved out of this process. The results of the present study indicate that the most valid and reliable factorial components of psychological well-being are self regard,interpersonal relationship, independence, problem-solving, assertiveness,reality testing, stress tolerance, self-actualization and happiness; social responsibility and flexibility emerged as questionable components of the a posteriori concept. The inventory which was designed to study the concept was successful in significantly differentiating various levels of psychological health. This way of conceptualizing and assessing psychological well-being has potential applicability for mental health practitioners and researchers.
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  • Date Issued: 1988

The doctrine of heaven in the writings of St. John of Damascus and earlier Greek tradition

- Parrish, Christopher John

  • Authors: Parrish, Christopher John
  • Date: 1988
  • Subjects: John, of Damascus, Saint
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: vital:1220 , http://hdl.handle.net/10962/d1001550
  • Description: This thesis investigates the subject of Heaven or Paradise in the De Fide Orthodoxa of St. John of Damascus (c.675 - c.749) , a Greek Father and theologian who gave the Church a definitive heritage of the Greek Fathers' teaching. After a preliminary consideration of the meanings of "Heaven" and Paradise as a state or a place, a substantial part of this thesis is then given to a detailed treatment of the Greek Fathers' teaching on the tree of the knowledge of good and evil and the tree of life in Paradise. The questions of the indispensability of the tree of life to the final bliss of the saints, and the doubtful place of the tree of knowledge also receive attention. The meaning of the trees for St. John of Damascus is expounded in order to show his use of the ideas of Greek Fathers prior to him, for example, Gregory Naziazenus and Maximus the Confessor. After this, the questions of entry into Paradise and the Greek teaching of the intermediate state of the departed are raised. The descent of Christ to Hades precedes discussion of whether St. John of Damascus taught a doctrine of Purgatory or not. The practice of prayer for the departed is examined with respect to its effect on the intermediate state of the faithful departed. Lastly, this thesis explores the necessity of the resurrection for the final bliss of the faithful, and establishes the relevance of this teaching for modern thought on the preservation of integral personality. In conclusion, the writer suggests that St. John of Damascus bequeathed to the Church rich insights into the Greek Fathers' doctrine of Heaven.
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  • Date Issued: 1988

The effect of elevated temperature on the nutrient requirements of rainbow trout, Salmo gairdneri (Pisces : Salmonidae) and the development of "least cost" feeds for trout production in South Africa

- McEwan, Anthony Graham

  • Authors: McEwan, Anthony Graham
  • Date: 1988
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:21150 , http://hdl.handle.net/10962/6606
  • Description: A review of trout metabolism, ingested energetic pathways, essential dietary nutrient requirements and the effect of water temperature on trout physiology identified the need to determine the effect of elevated temperatures (>18oC) on the nutrient requirements of rainbow trout. This review led to the hypothesis that as the temperature exceeds the optimum the growth potential of trout decreases with a theoretical concomitant decrease in the protein requirement. However, the increased metabolic rates of the fish should be reflected by an increased demand for lipids. The experiments designed to test this hypothesis revealed that at temperatures in excess of 18 oC the protein requirement for small (4.5g) and larger (>25g) juvenile rainbow trout are 40 and 35% respectively. This represents a decrease of 10% for the small juveniles and no change for larger juveniles compared to their requirements at optimum temperatures. The lipid requirements for the small as well as the larger juveniles increased by approximately 5 percent, to between 20 and 23 percent, compared to the requirement at optimum temperatures. Consequently the hypothesis was accepted. A review of practical diet formulation is presented along with a description of the experiments conducted to test several "least cost" diets under South African conditions. Recommendations that winter and summer diets be formulated and that the trout producers manufacture their own feeds are made. The most appropriate diet formulated and tested effected a 21 to 29.9 percent saving compared to the currently available feeds in South Africa.
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  • Date Issued: 1988

The establishment of a Lidar facility at Rhodes University

- Grant, Richard Peter James Seton

  • Authors: Grant, Richard Peter James Seton
  • Date: 1988
  • Subjects: Optical radar , LIDAR , Receiver , Transmitter , Photon counting electronics , Aerosol scattering , Temperature profiles , Stratosphere
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5445 , http://hdl.handle.net/10962/d1001998
  • Description: LIDAR is the optical equivalent of RADAR. A LIDAR facility has been established at Rhodes University using a flashlamp-pumped dye laser as the transmitter and a photomultiplier tube at the focus of a searchlight mirror as the receiver. The setting up of the receiver and transmitter as well as the design and construction of the photon counting electronics is described. The LIDAR has been used to measure aerosol scattering ratios and temperature profiles in the stratosphere and these results are presented with the algorithms and software used to reduce the data. Finally some recommendations are made for future work
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  • Date Issued: 1988

The functions of narrative : a study of recent novelistic nonfiction

- Carlean, Kevin John

  • Authors: Carlean, Kevin John
  • Date: 1988
  • Subjects: Reportage literature -- History and criticism , Nonfiction novel
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: vital:2176 , http://hdl.handle.net/10962/d1001827
  • Description: Since Truman Capote's In Cold Blood: A True Account of a Multiple Murder and its Consequences was published in 1965, there have been many attempts to define and explain the phenomenon of the "non-fiction novel" as a unified narrative genre. Some of these attempts have been highly theoretical and scholarly, but most have been rather loose definitions referring to an extremely wide range of diverse factual narratives. Over the years, so many different works have been called "non-fiction novels" that it now seems as if the notion of such a unified genre is questionable. Surely it is not generically useful to say that such functionally distinct works as Oscar Lewis's La Vida: A Puerto Rican Family in the Culture of Poverty (1967) and Hunter S. Thompson's Fear and Loathing in Las Vegas: A Savage Journey to the Heart ot the American Dream (1971) belong in the same narrative category. The purpose of this study is to show that many of the works routinely referred to as "non-fiction novels" perform fundamentally different narrative functions and do not belong together in a unified genre. Roman Jakobson's model of communication and his notion of the "dominant function" are used to identify three functional categories into which the narratives discussed in the study logically fall: first, there are predominantly sociological works in which the referential function is the most important element of the communication; second, there are predominantly journalistic works in which the opinions of the writer or emotive function constitute the central narrative concern; and thirdly, we have works performing a dominant novelistic or aesthetic function in the sense that the secondary meanings and themes implied are the most important elements communicated. The thesis follows the following structure. In the introductory chapter, a critique of some of the major generic theories of the "non-fiction novel" as unified genre is offered. The purpose here is not to caricature what are sometimes extremely sophisticated studies. (Indeed, in my own analysis of texts, I am often indebted to the critical insights of the scholars whose theories I question in the introduction.) My purpose is merely to show that the corpus of works each writer refers to can be divided more logically between different dominant narrative functions. The introduction ends with a more detailed explanation of the adaptation of Jakobson's notion of "the dominant" and how it relates to the functional categories identified. Chapter 2 offers analyses of a group of documentary narratives that perform a dominant sociological function but have often been referred to as "non-fiction novels." The chapter starts with an analysis of James Agee's Let Us Now Praise Famous Men (1941), a text widely regarded as the first real American example of the "genre." This is followed by an examination of the anthropological works of Oscar Lewis: Five Families: Mexican Case Studles in the Culture of Poverty (1959), The Children of Sanchez: Autobiography of a Mexican Family (1964), Pedro Martinez: A Mexican Peasant and his Family (1964) and La Vida: A Puerto Rican Family in the Culture of Poverty. I conclude the chapter with an analysis of the recent sociological works of Studs Terkel: Division Street: America (1968), Hard Times: An oral History of the Great Depression (1970) and Working: People talk about what they do all day and how they feel about what they do (1974). In Chapter 3, the notion of subjective participation journalism is explained. This is followed by an analysis of three of the most famous and creative of the works that fall into this functional category: Hunter S. Thompson's Hell's Angels: The Strange and Terrible Saga of an Outlaw Motorcycle Gang (1966), Michael Herr's Vietnam classic, Dispatches (1977), and Norman Mailer's account of a famous protest march, The Armies of the Night: History as a Novel, The Novel as History (1968). Chapter 4 offers a discussion of three works that perform a dominant novelistic function in the realistic tradition of Dostoevski's Crime and Punishment. All three are based on actual murder cases, but the facts of the stories are subordinated to the novelistic themes the author wishes to abstract. They are: Meyer Levin's Compulsion (1957), Mailer's The Executioner's Song (1979) and Capote's In Cold Blood. From this outline, it may appear as if the study is loaded in favour of the sociological works discussed in Chapter 2. This is intentional because, although many critics have referred to them as "non-fiction novels", very little systematic and detailed analysis of these works as a corpus has been forthcoming. This long chapter is an attempt to redress the balance.
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  • Date Issued: 1988

The geology and metallogeny of the Otavi mountain land, Damara orogen, SWA/Namibia, with particular reference to the Berg Aukas Zn-Pb-V deposit a model of ore genesis

- Misiewicz, Julian Edward

  • Authors: Misiewicz, Julian Edward
  • Date: 1988
  • Subjects: Geology -- Namibia -- Damaraland , Ore deposits -- Namibia , Orogeny , Metallogeny , Geodynamics
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4959 , http://hdl.handle.net/10962/d1005571 , Geology -- Namibia -- Damaraland , Ore deposits -- Namibia , Orogeny , Metallogeny , Geodynamics
  • Description: The Olavi Mountain Land is a 10 000 km2 mineral province located at the eastern extremity of the exposed Northern Platform of the Damara Pan African orogenic belt. The Olavi Mountain Land is tbe most important mineral province on the Northern Platform. Exploitation of tbe Cu-Pb-Zn-V province has been on-going since the possession of the territory by the German colonial authority in 1890. Production has been mostly from four mines which in order of importance are Tsumeb, Kombat, Berg Aukas and Abeoab. A second mineral province on the Northern Platform located in the west is centred on Sesfontein where as yet only insignificant mineralization has been noted. Besides these localities, the Northern Platform is conspicuously devoid of notable mineralization. The aim of this thesis has been to document tbe Berg Aukas deposit, an important end-member type of mineralization in the Otavi Mountain Land. The basic premise bas been to show tbat the derivation and localization of the mineralization is a consequence of two broad controls which can be simply summarised as features of the basement and of the carbonate sequences. The geodynamic evolution of the Damara Belt commenced with intra-continental rifting approximately 900 Ma ago. Rift grabens trending north-east were filled by the Nosib Group which comprises mostly clastic lithologies but also some volcanics. The earliest and largest rift is referred to as the Northern Rift. Separation of the Congo, Kalahari, and proto-South American cratons resulted in rifting and rapid downwarping so that an encroaching sea and an Olavi Group carbonate shelf developed along the northern margin of the Northern Rift. Significantly, the carbonates only covered the Northern Rift in the area of the Otavi Mountain Land where a basinal dome, referred to as the Grootfontein Basement High, marked the basin edge. In the west, the carbonates covered the less important Sesfonfein Rift, and it is only in these two areas where Nosib sequences underlie the carbonate platform. Carbonate sedimentation was interrupted by a major period of crustal readjustment and the deposition of an extensive mixtite throughout the geosynclinal Swakop Trough and Northern Platform. This is referred to as the Chuos Formation and subdivides the Olavi Group into a lower Abenab and an upper Tsumeb Subgroup. Reversal of spreading led to plate collision and subduction of tbe Kalahari craton beneath the Congo craton. It was accompanied by orogenesis which resulted in F1 folding of the Northern Platform into a series of north-easterly trending intermontane basins into which a molasse sequence known as the Mulden Group was unconformably deposited. Following this major north-south deformation mild east-west compression initiated F2 folding and the formation of doubly plunging synclines. The Berg Aukas Syncline represents a primary depositional basin which was subsequently folded. The original basin was formed by late Nosib rifting wben spreading caused the Swakop geosynclinal Trough to form. Carbonates of the basal Berg Aukas Formation were deposited in a lagoonal setting typified by reef and fore-reef facies witb peri-platform conditions. Rapid subsidence caused these sediments to be overlain by deep water carbonates of the Gauss Formation. Two styles of mineralization known as the Tsumeb-type and Berg Aukas-type are stratigraphically, isotopically, and mineralogically distinct. The Tsumeb-type is a cupriferous variety of discordant bodies confined to the upper sequences beneath the Mulden unconformity. The Berg Aukas-type is a Zn-Pb variety confined to tbe basal unconformity. The Berg Aukas deposit comprises three ore bodies known as the Northern Ore Horizon, the Central Ore Body, and the Hanging Wall Ore Body. Sphalerite and galena constitute the bypogene ore. Willemite, smithsonite, cerussite, and descloizite are important supergene ores. A review of genetic models concludes that a magmatic origin initially proposed for tbe Tsumeb deposit is entirely rejected and a basin dewatering model in line with Mississippi Valley-type deposits is proposed. The syntectonic nature of mineralization at Berg Aukas and elsewhere in the Otavi Mountain Land indicates that orogenesis encouraged dewatering and leaching of metals from a broad mineralizing front along the margin of the Swakop Trough. These were transported by acidic saline brines which migrated along the clastic aquifers and structural conduits provided by the Northern Rift. Fluid inclusion studies indicate that the hydrothermal fluids at Berg Aukas were very saline (23% TDS) and were transported at temperatures ranging between 92° to 210°C. Hydrothermal fluids which mineralized Berg AukaS-type deposits migrated along the basal unconformity towards the basement high and were responsible for hydrothermally altering the basement granites and gabbros and the Nosib clastic rocks. Tsumeb-type deposits resulted by migration of fluids through the carbonate pile and along north-easterly trending basement geofractures. As a consequence of variation in transport, the Berg Aukas-type and Tsumeb-type fluids leached different sources and therefore derived mineralogically and isotopically seperable characteristics. The localization of the Berg Aukas ores was controlled by the carbonate stratigraphy and structure. Hydrothermal karsting and ore deposition took place on the contact between Massive Grey and Light Grey Dolostones which represents a permeability contrast. The movement of the hydrothermal fluids was controlled by north-south trending vertical fractures caused by F2 folding which resulted in a peric1inal structure. Hydrothermal karsting was accompanied by ca1citic, dolomitic and silicic alteration. The heated acidic fluids initiated solution collapse and a variety of breccia types. Supergene processes resulted in oxidation and upgrading of the ore. Vanadium derived indirectly from gabbros in the basement complex were transported as calcium metavanadate complexes and deposited on contact with the oxidizing base metal sulphides.
  • Full Text:
  • Date Issued: 1988
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