Log in

Relevant bibliographies by topics / Mineralogy – South Africa / Journal articles

To see the other types of publications on this topic, follow the link: Mineralogy – South Africa.

Journal articles on the topic 'Mineralogy – South Africa'

Author: Grafiati

Published: 4 June 2021

Last updated: 12 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Mineralogy – South Africa.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Hammond, A. L., and R. H. Mitchell. "Accessory mineralogy of orangeite from Swartruggens, South Africa." Mineralogy and Petrology 76, no. 1-2 (September 1, 2002): 1–19. http://dx.doi.org/10.1007/s007100200029.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

van der Merwe, Gertruida M. E., Michiel C. Laker, and Christl Bühmann. "Clay mineral associations in melanic soils of South Africa." Soil Research 40, no. 1 (2002): 115. http://dx.doi.org/10.1071/sr00097.

Full text

Abstract:

The melanic horizon is 1 of 5 diagnostic topsoil horizons distinguished in the South African soil classification system. Melanic soils span a wide spectrum, ranging from those that intergrade with a vertic to those that intergrade with a humic horizon. Melanic soils are therefore expected to vary considerably with respect to a variety of physical, chemical, and clay mineralogical properties. The objective of the present study was to determine the clay mineral compositions of melanic horizons from 58 modal profiles and to establish to what extent melanic soil properties are related to clay mineralogy. Special emphasis was placed on the characterisation of the clay fraction in terms of group and species identification. X-ray diffractometry was employed almost exclusively as the investigative technique in mineral identification and quantification. Melanic A horizons showed a large degree of variation with regard to their clay mineral associations. More than half of the soils were dominated by smectite, 30&percnt; by kaolinite, and the rest by an association of about equal proportions of mica, kaolinite, and smectite. Talc and hydroxy-interlayered vermiculite occurred in a number of soils while one horizon was dominated by an illite/smectite interstratification. The smectite component was identified as belonging to either beidellite or vermiculite species, depending on the method employed. About a quarter of the smectitic soils contained montmorillonite as well but not as the dominant swelling phase. mollisols, clay mineralogy, layer charge.

APA, Harvard, Vancouver, ISO, and other styles

3

Bühmann, C., B. J. Escott, and J. C. Hughes. "Soil mineralogy research in South Africa, 1978 to 2002 - a review." South African Journal of Plant and Soil 21, no. 5 (January 2004): 316–29. http://dx.doi.org/10.1080/02571862.2004.10635067.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Starostin, V. I., A. L. Perchuk, and A. V. Bobrov. "35th Session of the InternationalGeological Congress (Cape Town, 2016)." Moscow University Bulletin. Series 4. Geology, no. 3 (June 28, 2017): 3–6. http://dx.doi.org/10.33623/0579-9406-2017-3-3-6.

Full text

Abstract:

The results of the 35th Session of the International Geological Congress held in 2016 in Cape Town (South Africa) are discussed in this paper. The major scientific problems discussed at the most popular sections are considered. Among them are the early stages in the evolution of the Earth, studies of mineral resources worldwide, the problems of the deep Earth structure, as well as modern fields of mineralogy.

APA, Harvard, Vancouver, ISO, and other styles

5

Mandiringana, O. T., P. N. S. Mnkeni, Z. Mkile, W. van Averbeke, E. Van Ranst, and H. Verplancke. "Mineralogy and Fertility Status of Selected Soils of the Eastern Cape Province, South Africa." Communications in Soil Science and Plant Analysis 36, no. 17-18 (October 2005): 2431–46. http://dx.doi.org/10.1080/00103620500253514.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Monatshebe, Tshiyoyo, Antoine F. Mulaba-Bafubiandi, and Didier Kasongo Nyembwe. "Mechanical properties and mineralogy of artisanal clay bricks manufactured in Dididi, Limpopo, South Africa." Construction and Building Materials 225 (November 2019): 972–82. http://dx.doi.org/10.1016/j.conbuildmat.2019.07.247.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

G I, E. Ekosse, de Jager L, and Ngole V. "Traditional mining and mineralogy of geophagic clays from Limpopo and Free State provinces, South Africa." African Journal of Biotechnology 9, no. 47 (November 22, 2010): 8058–67. http://dx.doi.org/10.5897/ajb10.296.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Oberthür, Thomas, Frank Melcher, Tobias Fusswinkel, Alfons M. van den Kerkhof, and Graciela M. Sosa. "The hydrothermal Waterberg platinum deposit, Mookgophong (Naboomspruit), South Africa. Part 1: Geochemistry and ore mineralogy." Mineralogical Magazine 82, no. 3 (April 12, 2018): 725–49. http://dx.doi.org/10.1180/minmag.2017.081.073.

Full text

Abstract:

ABSTRACTThe Waterberg platinum deposit is an extraordinary example of a vein-type hydrothermal quartz-hematite-PGE (platinum-group element) mineralization. This study concentrates on the geochemical character of the ores and the platinum-group mineral (PGM) assemblage by application of reflected-light and scanning electron microscopy followed by electron probe microanalysis.The PGM-bearing quartz veins show multiple banding indicating numerous pulses of fluid infiltration. Mineralization was introduced contemporaneously with the earliest generation of vein quartz and hematite. High oxygen and low sulfur fugacities of the mineralizing fluids are indicated by hematite as the predominant opaque mineral and the lack of sulfides.The ‘Waterberg type’ mineralization is characterized by unique metal proportions, namely Pt>Pd>Au, interpreted as a fingerprint to the cradle of the metals, namely rocks and ores of the Bushveld Complex, or reflecting metal fractionation during ascent of an oxidized, evolving fluid. The PGM assemblage signifies three main depositional and alteration events. (1) Deposition of native Pt and Pt–Pd alloys (>90% of the PGM assemblage) and Pd–Sb–As compounds (Pt-rich isomertieite and mertieite II) from hydrothermal fluids. (2) Hydrothermal alteration of Pt by Cu-rich fluids and formation of Pt–Cu alloys and hongshiite [PtCu]. (3) Weathering/oxidation of the ores producing Pd/Pt-oxides/hydroxides.Platinum-group element transport was probably by chloride complexes in moderately acidic and strongly oxidizing fluids of relatively low salinity, and depositional temperatures were in the range 400–200°C. Alternatively, quartz and ore textures may hint to noble metal transport in a colloidal form and deposition as gels.The source of the PGE is probably in platiniferous rocks or ores of the Bushveld Complex which were leached by hydrothermal solutions. If so, further Waterberg-type deposits may be present, and a prime target area would be along the corridor of the Thabazimbi-Murchison-Lineament where geothermal springs are presently still active.

APA, Harvard, Vancouver, ISO, and other styles

9

Pharoe, Benedick Kinshasa, A. N. Evdokimov, I. M. Gembitskaya, Christopher Baiyegunhi, and Zusakhe Nxantsiya. "Mineralogy, geochemistry and geological occurrence of supergene manganese ore mineralization in North West Province, South Africa." Russian Journal of Earth Sciences 20, no. 5 (August 22, 2020): 1–19. http://dx.doi.org/10.2205/2020es000703.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Eze, Peter N., and Michael E. Meadows. "Mineralogy and micromorphology of a late Neogene paleosol sequence at Langebaanweg, South Africa: Inference of paleoclimates." Palaeogeography, Palaeoclimatology, Palaeoecology 409 (September 2014): 205–16. http://dx.doi.org/10.1016/j.palaeo.2014.05.008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Mishra, G., K. S. Viljoen, and H. Mouri. "Influence of mineralogy and ore texture on pentlandite flotation at the Nkomati nickel mine, South Africa." Minerals Engineering 54 (December 2013): 63–78. http://dx.doi.org/10.1016/j.mineng.2013.04.009.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Gutzmer, J., and N. J. Beukes. "Mineralogy and mineral chemistry of oxide-facies manganese ores of the Postmasburg manganese field, South Africa." Mineralogical Magazine 61, no. 405 (April 1997): 213–31. http://dx.doi.org/10.1180/minmag.1997.061.405.05.

Full text

Abstract:

AbstractThe diagenetic to very low-grade metamorphic manganese ores of the Postmasburg manganese field provide a unique example of oxide-facies manganese ores in a Palaeoproterozoic palaeokarst setting. The ores are composed mainly of braunite group minerals, including braunite, partridgeite and bixbyite, with rare braunite II and Ca-poor, silica-depleted braunite. Iron-poor partridgeite is distinguished from Fe-rich bixbyite and the occurrence of Ca-poor, silica-depleted braunite is reported for the first time. Braunite and partridgeite formed during early diagenesis but remained stable under greenschist facies metamorphic conditions. In contrast, bixbyite is apparently a product of metasomatic remobilisation under peak metamorphic conditions. It is suggested that local variations of the metamorphic mineral association reflect variations of the host rock composition and that they are not related to changing P-T conditions of metamorphic alteration, a model promoted by previous authors. The phase chemistry of braunite, braunite II and bixbyite is explained by the existing polysomatic stacking model for the braunite group. However, the chemical composition of partridgeite and Ca-poor, silica-depleted braunite can only be explained by introducing a distinct module layer, with partridgeite composition, to the existing polysomatic stacking model.

APA, Harvard, Vancouver, ISO, and other styles

13

Nciizah, AD, and IIC Wakindiki. "Particulate organic matter, soil texture and mineralogy relations in some Eastern Cape ecotopes in South Africa." South African Journal of Plant and Soil 29, no. 1 (June 2012): 39–46. http://dx.doi.org/10.1080/02571862.2012.688882.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Sumner, Dawn Y., and John P. Grotzinger. "Implications for Neoarchaean ocean chemistry from primary carbonate mineralogy of the Campbellrand-Malmani Platform, South Africa." Sedimentology 51, no. 6 (December 2004): 1273–99. http://dx.doi.org/10.1111/j.1365-3091.2004.00670.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Wagner, N. J., M. L. Mokwena, and A. Kolker. "Occurrence and probable source of chromium enrichment in Permian coals, South Africa." South African Journal of Geology 124, no. 3 (September 1, 2021): 611–26. http://dx.doi.org/10.25131/sajg.124.0013.

Full text

Abstract:

Abstract The trace element data pool for South African coals is limited. However, certain elements are reported as occurring in considerably higher concentrations than global average values. These elements include chromium (Cr), as well as manganese (Mn), cobalt (Co), and molybdenum (Mo), with Cr showing the most consistent enrichment. The aim of this study was to investigate the occurrence of Cr in South African coals sampled from five coalfields, and to assess the possible source of Cr. A total of 21 run-of-mine (ROM) coal samples from the Waterberg, Soutpansberg, Witbank, Highveld, and the Nongoma Coalfields were obtained from active mines. Coal characterization, mineralogy, and geochemical data were compiled. The Cr values for the Waterberg (23 to 28 ppm), Soutpansberg (4.7 to 43 ppm), Witbank (24 to 37 ppm), and Highveld (33 to 37 ppm) coal samples are higher than those for the Nongoma coals (1.2 to 2.5 ppm), and, in nearly every case, higher than the Clarke value for hard coals (17 ppm). Correlation coefficients, density fractionation, and selective leaching were used to infer (indirect) modes of occurrence. A dominant silicate (clay) affinity was determined with Cr, as well as an organic affinity in the ROM samples. The Nongoma coals, with illite and no kaolinite, have extremely low Cr values. The other samples are enriched in kaolinite and also have a high Cr content. Chromium values as high as 67 ppm were reported for 1.4 RD float fraction samples, indicating a positive correlation with organic matter. A Cr - silicate association was observed following selective leaching. These results imply multiple modes of occurrence of Cr in the South African samples, in agreement with studies conducted globally. Chromium in the South African coals could have originated from the Bushveld Complex (approximately two billion years old), the largest Cr reserve in South Africa, which predates coal formation (approximately 299 to 252 million years ago) and is proximal to the coalfields. The Cr, seemingly not associated with chromite, may have been redistributed in the peat swamps during peat deposition, accumulating in the sediments and organic material. The Nongoma Coalfield is the farthest distance from the possible Bushveld Complex Cr source, and these samples are depleted in Cr.

APA, Harvard, Vancouver, ISO, and other styles

16

Hall, Grant, Lyn Wadley, and Stephan Woodborne. "Past Environmental Proxies from the Middle Stone Age at Sibudu, Kwazulu-Natal, South Africa." Journal of African Archaeology 12, no. 1 (November 1, 2014): 7–24. http://dx.doi.org/10.3213/2191-5784-10246.

Full text

Abstract:

Middle Stone Age technological and behavioural developments in southern Africa are central to understanding the emergence of modern humans, and elucidating the role of environmental change in this trajectory is dependent on emerging palaeoclimatic reconstructions. Climate proxies from Middle Stone Age sites are often poorly preserved, coarsely resolved or subject to anthropogenic selection and are not considered in favour of global environmental proxies despite the fact that the modern climate regimes at the relevant archaeological sites differ profoundly. Sibudu has a well-preserved Middle Stone Age sequence that has yielded abundant palaeoclimate proxy data. Isotopic analysis of charcoal, charcoal anatomy and species representation, macro- and micro-faunal remains, sediment texture, mineralogy and magnetic susceptibility, pollen and macrobotanical remains provide evidence for the environmental succession specific to this site. The isotopic data suggest that archaeological charcoal was not significantly post-depositionally altered. During the Howiesons Poort (65–62 ka) the local environment was thickly forested, moist and more humid than during the 58 ka occupations. The environment changes during the post-Howiesons Poort occupation (~58 ka) into the late MSA occupation (~48 ka); conditions became drier and colder than present with vegetation shifting to open savanna grassland or woodlands.

APA, Harvard, Vancouver, ISO, and other styles

17

Miyano, T., and N. J. Beukes. "Mineralogy and Petrology of the Contact Metamorphosed Amphibole Asbestos-bearing Penge Iron Formation, Eastern Transvaal, South Africa." Journal of Petrology 38, no. 5 (May 1, 1997): 651–76. http://dx.doi.org/10.1093/petroj/38.5.651.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Altigani, Mohammed Alnagashi Hassan. "Studies on the Ore Mineralogy and Litho-geochemistry of the Sheba Deposit, Barberton Greenstone Belt, South Africa." Economic and Environmental Geology 54, no. 2 (April 30, 2021): 213–32. http://dx.doi.org/10.9719/eeg.2021.54.2.213.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

O’Connor, Cyril, and Tatiana Alexandrova. "The Geological Occurrence, Mineralogy, and Processing by Flotation of Platinum Group Minerals (PGMs) in South Africa and Russia." Minerals 11, no. 1 (January 7, 2021): 54. http://dx.doi.org/10.3390/min11010054.

Full text

Abstract:

Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.

APA, Harvard, Vancouver, ISO, and other styles

20

O’Connor, Cyril, and Tatiana Alexandrova. "The Geological Occurrence, Mineralogy, and Processing by Flotation of Platinum Group Minerals (PGMs) in South Africa and Russia." Minerals 11, no. 1 (January 7, 2021): 54. http://dx.doi.org/10.3390/min11010054.

Full text

Abstract:

Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.

APA, Harvard, Vancouver, ISO, and other styles

21

Graupner, Torsten, Caroline Mühlbach, Ulrich Schwarz-Schampera, Friedhelm Henjes-Kunst, Frank Melcher, and Hennie Terblanche. "Mineralogy of high-field-strength elements (Y, Nb, REE) in the world-class Vergenoeg fluorite deposit, South Africa." Ore Geology Reviews 64 (January 2015): 583–601. http://dx.doi.org/10.1016/j.oregeorev.2014.02.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Bühmann, C., and W. F. A. Kirsten. "The mineralogy of five weathering profiles developed from Archaean granite in the eastern Transvaal, Republic of South Africa." South African Journal of Plant and Soil 8, no. 3 (January 1991): 146–52. http://dx.doi.org/10.1080/02571862.1991.10634823.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Waters, D. J., and J. M. Moore. "Kornerupine in Mg-Al-rich gneisses from Namaqualand, South Africa: mineralogy and evidence for late-metamorphic fluid activity." Contributions to Mineralogy and Petrology 91, no. 4 (December 1985): 369–82. http://dx.doi.org/10.1007/bf00374693.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Grandstaff, D. E., M. J. Edelman, R. W. Foster, E. Zbinden, and M. M. Kimberley. "Chemistry and mineralogy of Precambrian paleosols at the base of the Dominion and Pongola Groups (Transvaal, South Africa)." Precambrian Research 32, no. 2-3 (July 1986): 97–131. http://dx.doi.org/10.1016/0301-9268(86)90003-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Klemd, R., and J. M. Barton. "Mineralogy and geochemistry of the hydrothermally altered archaean granodioritic rocks of the ventersdorp dome, Western Transvaal, South Africa." Mineralogy and Petrology 38, no. 3 (May 1988): 151–60. http://dx.doi.org/10.1007/bf01164698.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Oyebanjo, O. O., G. E. Ekosse, and J. O. Odiyo. "Mineralogy and geochemistry of clay fractions in soils developed from different parent rocks in Limpopo Province, South Africa." Heliyon 7, no. 7 (July 2021): e07664. http://dx.doi.org/10.1016/j.heliyon.2021.e07664.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Wronkiewicz, David J., and Kent C. Condie. "Geochemistry and mineralogy of sediments from the Ventersdorp and Transvaal Supergroups, South Africa: Cratonic evolution during the early Proterozoic." Geochimica et Cosmochimica Acta 54, no. 2 (February 1990): 343–54. http://dx.doi.org/10.1016/0016-7037(90)90323-d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Koeberl, Christian, Wolf Uwe Reimold, and Rudolf H. Boer. "Geochemistry and mineralogy of Early Archean spherule beds, Barberton Mountain Land, South Africa: evidence for origin by impact doubtful." Earth and Planetary Science Letters 119, no. 3 (September 1993): 441–52. http://dx.doi.org/10.1016/0012-821x(93)90152-y.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Maya, M., M. Sutton, H. Tutu, and I. Weiersbye. "Mineralogy and heavy metal content of secondary mineral salts: A case study from the Witwatersrand Gold Basin, South Africa." South African Journal of Geomatics 4, no. 2 (June 26, 2015): 161. http://dx.doi.org/10.4314/sajg.v4i2.8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Nkosi, Nomqhele Z., Musa S. D. Manzi, Gillian R. Drennan, and Halil Yilmaz. "Experimental measurements of seismic velocities on core samples and their dependence on mineralogy and stress; Witwatersrand Basin (South Africa)." Studia Geophysica et Geodaetica 61, no. 1 (November 24, 2016): 115–44. http://dx.doi.org/10.1007/s11200-016-0804-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Stalder, M., and A. Rozendaal. "Graftonite in phosphatic iron formations associated with the mid-Proterozoic Gamsberg Zn-Pb deposit, Namaqua Province, South Africa." Mineralogical Magazine 66, no. 6 (December 2002): 915–27. http://dx.doi.org/10.1180/0026461026660067.

Full text

Abstract:

Abstract Granular aggregates of fine-grained graftonite (Fe,Mn,Ca)3(PO4)2 and intergrown wolfeite (Fe,Mn)2(PO4)(OH) occur in amphibolite-facies metamorphosed iron formations associated with the Gamsberg Zn-Pb deposit, South Africa. To date, these minerals were believed to have limited parageneses, being essentially restricted to granitic pegmatites and iron meteorites. This paper is the first report of the occurrence of graftonite and wolfeite in a regionally metamorphosed, iron formation-hosted setting. The aggregates are found together with Mn- and Pb-rich apatite and calcian pyromorphite in a pristine unit of almost pure chemical precipitates, the origin of which is intimately linked to the base-metal mineralizing process. Evidence from Gamsberg supports previous studies conducted on pegmatite-hosted graftonites that a simple host rock mineralogy and geochemical prerequisites, such as high activities of Fe, Mn, Ca and a deficiency in F, exert a dominant control on the stabilization of these minerals. However, in a marine sedimentary environment, significant concentrations of phosphorus have to be precipitated to prevent stabilization of all the phosphorus as fluorapatite. The paucity of graftonite in such settings suggests that the combination of these requirements is only rarely achieved.

APA, Harvard, Vancouver, ISO, and other styles

32

Jordaan, Gerrit J., and Wynand J. vdM Steyn. "Nanotechnology Incorporation into Road Pavement Design Based on Scientific Principles of Materials Chemistry and Engineering Physics Using New-Age (Nano) Modified Emulsion (NME) Stabilisation/Enhancement of Granular Materials." Applied Sciences 11, no. 18 (September 14, 2021): 8525. http://dx.doi.org/10.3390/app11188525.

Full text

Abstract:

The use of naturally available materials not conforming to traditional specifications or standards in the base and sub-base layers of road pavement structures and stabilised with New-age (Nano) Modified Emulsions (NME) have been tested, implemented and successfully verified through Accelerated Pavement Testing (APT) in South Africa. This was made possible through the development and use of a materials design procedure addressing fundamental principles and based on scientific concepts which are universally applicable. The understanding and incorporation of the chemical interactions between the mineralogy of the materials and an NME stabilising agent (compatibility between the chemistry of the reactive agents and material mineralogy) into the design approach is key to achieving the required engineering properties. The evaluation of the stabilised materials is performed using tests indicative of the basic engineering properties (physics) of compressive strengths, tensile strengths and durability. This article describes the basic materials design approach that was developed to ensure that organofunctional nano-silane modified emulsions can successfully be used for pavement layer construction utilising naturally available materials at a low risk. The enablement of the use of naturally available materials in all pavement layers can have a considerable impact on the unit cost and lifecycle costs of road transportation infrastructure.

APA, Harvard, Vancouver, ISO, and other styles

33

Mielke, Christian, Nina Boesche, Christian Rogass, Hermann Kaufmann, Christoph Gauert, and Maarten de Wit. "Spaceborne Mine Waste Mineralogy Monitoring in South Africa, Applications for Modern Push-Broom Missions: Hyperion/OLI and EnMAP/Sentinel-2." Remote Sensing 6, no. 8 (July 25, 2014): 6790–816. http://dx.doi.org/10.3390/rs6086790.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Philander, C., and A. Rozendaal. "A process mineralogy approach to geometallurgical model refinement for the Namakwa Sands heavy minerals operations, west coast of South Africa." Minerals Engineering 65 (October 2014): 9–16. http://dx.doi.org/10.1016/j.mineng.2014.04.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Ayodele, Irewole, Chiara Cavalleri, Adeleke Orimolade, and Babafemi Falaye. "Advances in Elemental Spectroscopy Logging: A Cased Hole Application Offshore West Africa." Journal of Geography and Geology 9, no. 4 (November 30, 2017): 63. http://dx.doi.org/10.5539/jgg.v9n4p63.

Full text

Abstract:

Rising costs for exploration and developments and more stringent need to secure any additional drop of oil have put operators’ margins under increasing pressure. Coupled with the recent oil price decline, this call for efficiency and diligence to be the main drivers for any formation evaluation and planning for development and production. The reservoirs in Western offshore Africa are so diverse in the settings that two reservoirs hardly show any correlation. The complexity associated with the Rifting of African plate from South American plate has introduced significant geological challenges, adding to even bigger challenges in Petrophysical analysis. The mineralogy is complex; clay characterization is often unsolved. The formation waters are fresh with variable salinity and there is occurrence of thin shale laminations and grain size variations contributing to low resistivity low contrast pay generation. Advanced and fit-to-purpose logging technologies and computational methods are needed for rock quality and potential. Moreover, in some cases the accessibility of the target reservoir is difficult and risky, so that formation evaluation must be performed behind casing.The high definition spectroscopy tool is the latest development in wireline spectroscopy measurements. Its technological advances revolutionize the neutron-induced gamma ray methodology to support robust lithology and saturation interpretation in formations with complex mineralogy and fluid content. The ability to determine both the matrix mineral composition and total organic carbon (TOC) are instrumental to the geoscientist, the petrophysicist, the reservoir engineer, and the completion engineer. In the region, the use of high definition spectroscopy measurement has been pioneered while pursuing better understanding of rock composition and more accurate reservoir models in complex lithology and fresh formation waters with low resistivity contrast. The results are beneficial at the various stages of a field development and provide critical input to the petrophysical reserves estimate.In the example described in this paper, the new technology has proven to be critical to evaluate a complex reservoir system independent of the water salinity and resistivity offshore Gulf of Guinea, even with logging behind casing. A comprehensive set of quality outputs is made available for accurate reservoir quality; the logs data processing is performed within the critical-hours after logging to enable informed decision making.

APA, Harvard, Vancouver, ISO, and other styles

36

Andersson, P. O. D., and R. H. Worden. "Stratigraphic variations in mudstone mineral assemblages from a submarine fan-complex: Karoo Basin, South Africa." Clay Minerals 41, no. 4 (December 2006): 839–52. http://dx.doi.org/10.1180/0009855064140223.

Full text

Abstract:

AbstractDespite the high-grade diagenesis experienced by the Skoorsteenberg Formation mudstones, Tanqua Karoo basin, South Africa, geochemical data have been interpreted to reveal primary mineralogy and so help understand provenance evolution. The geochemical signatures show systematic variations related to stratigraphy. The main changes in mudstones from the lower to the upper part of the section include: (1) an increase in the feldspar content of the primary sediment and a decrease in the content of Al-rich clay (probably dioctahedral smectite); (2) a decrease in the degree of chemical weathering of the sediment, representing a change to a dryer and/or cooler climate; (3) an increase in TiO2/Al2O3 representing increasing mafic sources; (4) an increase in CaO/(K2O+CaO) also possibly representing increasing mafic sources. Mass flux and differential diagenesis are unlikely to be responsible for the depth-related changes since the rocks have undergone the same degree of high-grade diagenesis and the mudstones are interrupted by other lithologies, so disturbing any sort of diffusion gradient. These variations could plausibly be the result of one or more of differential weathering, evolving provenance characteristics or variable hydrodynamic fractionation of the sediment. The ratio of Zr/Y, a possible indicator of hydrodynamic fractionation, increases only slightly and irregularly up-section. There is no relationship between the silica content, representative of the quartz-silt content of the sediment, and TiO2/Al2O3 showing that the amount of quartz, and so the degree of hydrodynamic fractionation, has not controlled mudstone geochemistry. The stratigraphic increase in feldspar content, the decrease in Al-rich clay content and increase of both TiO2/Al2O3 and CaO/(K2O+CaO) must be due to a combination of marginally evolving provenance characteristics (more mafic and felsic rocks exposed to weathering with time) and changes in the degree of rock weathering (less chemical weathering with time).

APA, Harvard, Vancouver, ISO, and other styles

37

Cabri, L. J., A. M. McDonald, C. J. Stanley, N. S. Rudashevsky, G. Poirier, H. R. Wilhelmij, W. Zhe, and V. N. Rudashevsky. "Palladosilicide, Pd2Si, a new mineral from the Kapalagulu Intrusion, Western Tanzania and the Bushveld Complex, South Africa." Mineralogical Magazine 79, no. 2 (April 2015): 295–307. http://dx.doi.org/10.1180/minmag.2015.079.2.08.

Full text

Abstract:

AbstractPalladosilicide, Pd2Si, is a new mineral (IMA 2014-080) discovered in chromite-rich samples from the Kapalagulu intrusion, western Tanzania (30°03′51′′E 5°53′16′′S and 30°05′37′′E 5°54′26′′S) and from the UG-2 chromitite, Bushveld complex, South Africa. A total of 13 grains of palladosilicide, ranging in size from 0.7 to 39.1 μm (equivalent circle diameters), were found. Synthetic Pd2Si is hexagonal, space group P62m, with a = 6.496(5), c = 3.433(4) Å, V = 125.5(1) Å3, c:a = 0.529 with Z = 3. The strongest lines calculated from the powder pattern (Anderko and Schubert, 1953) are [d in Å (I) (hkl)] 2.3658 100 (111); 2.1263 37 (120); 2.1808 34 (021); 3.240 20 (110); 1.8752 19 (030); 1.7265 12 (002); 1.3403 11 (122); 1.2089 10 (231). The calculated density for three analyses varies from 9.562 to 9.753 g cm–3. Palladosilicide is considered to be equivalent to synthetic Pd2Si based on results from electron backscattered diffraction analyses. Reflectance data in air for the four Commission on Ore Mineralogy wavelengths are [λ nm, R1 (%) R2 (%)] 470 49.6 52.7; 546 51.2 53.8; 589 51.6 53.7; 650 51.7 53.3 and the mineral is bright creamy white against chromite, weakly bireflectant and displays no discernible pleochroism or twinning. It is weakly anisotropic, has weak extinction and rotation tints in shades of blue and olive green. Electron probe microanalyses of palladosilicide yield a simplified formula of Pd2Si.

APA, Harvard, Vancouver, ISO, and other styles

38

Kawohl, Alexander, and Hartwig E. Frimmel. "Isoferroplatinum-pyrrhotite-troilite intergrowth as evidence of desulfurization in the Merensky Reef at Rustenburg (western Bushveld Complex, South Africa)." Mineralogical Magazine 80, no. 6 (October 2016): 1041–53. http://dx.doi.org/10.1180/minmag.2016.080.055.

Full text

Abstract:

AbstractPetrographic and mineralogical studies of samples of the Normal (or undisturbed) Merensky Reef from Frank Shaft No.1 at Rustenburg Platinum Mine revealed the presence of a Pt-Fe-alloy, probably isoferroplatinum (58 vol.% of total precious metal minerals), arsenides (21 vol.%), bismuthotellurides (10 vol.%), electrum (9 vol.%) and platinum group element- (PGE-) sulfides and stannides (2 vol.%), associated predominantly with base-metal- and iron-sulfides. A Pt-Fe-alloy-dominated facies has been known for considerable time from potholes and discordant bodies and has been attributed to fluid activity with high fO2and low fS2. Our petrographic results indicate that the normal thin reef has also undergone hydrothermal alteration. For the first time, the rare mineral troilite (stoichiometric FeS) was found as intergrowths with masses of Pt-Fe-alloy, together with Fe-rich pyrrhotite, secondary hydrous silicates, magnetite and calcite. The observed mineral assemblage and texture is interpreted as the product of partial desulfurization, caused by migrating S-undersaturated fluids, which led to the exsolution of Pt-Fe-alloy from pyrrhotite (Fex–1S) with the latter approaching a stoichiometric composition. Overall our new observations provide convincing support for the importance of metasomatism in the secondary modification of ore mineralogy and textures even in the undisturbed Merensky Reef.

APA, Harvard, Vancouver, ISO, and other styles

39

Poujol, M., J. Jaguin, J.-F. Moyen, P. Boulvais, and J.-L. Paquette. "Archaean S-Type granites: petrology, geochemistry and geochronology of the Lekkersmaak and Willie plutons, Kaapvaal Craton, South Africa." South African Journal of Geology 124, no. 1 (March 1, 2021): 87–110. http://dx.doi.org/10.25131/sajg.124.0004.

Full text

Abstract:

Abstract S-type granites correspond to reworking of pre-existing continental material and form by partial melting of (meta)sediments. Early-to-mid Archaean S-type granites are rare and are more frequently found, usually as relatively small intrusions, during the Neoarchaean and the Archaean-Proterozoic transition. In the context of Archaean geology, their paucity is therefore significant, in that it matches the uncommon nature of processes during this period. In this study, we focus on the Late Mesoarchaean Willie pluton and Neoarchaean Lekkersmaak pluton, which crop out to the south of the Murchison Greenstone Belt in the Northern Kaapvaal Craton, South Africa. These intrusions represent the oldest S-type plutons known so far in the region. We constrain their petrogenesis by documenting their petrology, mineralogy (mineral composition), geochemistry (major and trace elements, Sr, Nd and O isotopes) and zircon U-Pb geochronology. The large Lekkersmaak and smaller Willie plutons represent two granites sharing many geochemical characteristics; they are both peraluminous, Ms-bearing S-type granites although they are more sodic and less potassic than typical S-type granites. The Willie granite was emplaced 2 816 ± 9 Ma ago while the Lekkersmaak yielded an emplacement age of 2 771 ± 2 Ma. Therefore, S-Type magmatism in the area occurred twice at 2.82 Ga and then 40 Myr later at 2.77 Ga, involving comparable immature metasedimentary sources and conditions of partial melting. Finally, a sample from the Lekkersmaak pluton devoid of S-type features as it is muscovite-free and aluminum poor was emplaced 2 734 ± 11 Ma ago. This confirms the episodic nature of magmatic activity south of the Murchison Greenstone Belt.

APA, Harvard, Vancouver, ISO, and other styles

40

Pharoe, Benedict Kinshasa, Alexander Nikolaevich Evdokimov, Irina Mikhailovna Gembitskaya, and Yakov Yurievich Bushuyev. "Mineralogy, geochemistry and genesis of the post-Gondwana supergene manganese deposit of the Carletonville-Ventersdorp area, North West Province, South Africa." Ore Geology Reviews 120 (May 2020): 103372. http://dx.doi.org/10.1016/j.oregeorev.2020.103372.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Taylor, Lawrence A., and Clive R. Neal. "Eclogites with Oceanic Crustal and Mantle Signatures from the Bellsbank Kimberlite, South Africa, Part I: Mineralogy, Petrography, and Whole Rock Chemistry." Journal of Geology 97, no. 5 (September 1989): 551–67. http://dx.doi.org/10.1086/629334.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Tibane, L. V., H. Pöllmann, F. L. Ndongani, B. Landman, and W. Altermann. "Evaluation of the lithofacies, petrography, mineralogy, and geochemistry of the onshore Cretaceous Zululand Basin in South Africa for geological CO2 storage." International Journal of Greenhouse Gas Control 109 (July 2021): 103364. http://dx.doi.org/10.1016/j.ijggc.2021.103364.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Smith, J. W., D. A. Holwell, and I. McDonald. "The mineralogy and petrology of platinum-group element-bearing sulphide mineralisation within the Grasvally Norite–Pyroxenite–Anorthosite (GNPA) member, south of Mokopane, northern Bushveld Complex, South Africa." Applied Earth Science 120, no. 4 (December 2011): 158–74. http://dx.doi.org/10.1179/1743275812y.0000000014.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Vymazalová, Anna, Federica Zaccarini, Giorgio Garuti, František Laufek, Daniela Mauro, Chris J. Stanley, and Cristian Biagioni. "Bowlesite, PtSnS, a new platinum group mineral (PGM) from the Merensky Reef of the Bushveld Complex, South Africa." Mineralogical Magazine 84, no. 3 (April 29, 2020): 468–76. http://dx.doi.org/10.1180/mgm.2020.32.

Full text

Abstract:

AbstractBowlesite is a new mineral discovered in the Merensky Reef of the Rustenburg Platinum Mine, Bushveld complex, South Africa. Bowlesite forms tiny grains (maximum dimension 20 μm). It is associated with sulfides including chalcopyrite, pyrrhotite and pentlandite, in contact with silicates including plagioclase, pyroxene- and minor serpentine-subgroup and amphibole-supergroup minerals. Bowlesite is brittle and has a metallic lustre. In plane-polarised light, bowlesite has a light bluish grey colour. It shows weak bireflectance, no pleochroism and has weak anisotropism. Internal reflections were not observed. Reflectance values of bowlesite in air (R1, R2 in %) are: 50.3–51.4 at 470 nm, 48.5–48.9 at 546 nm, 47.9–48.6 at 589 nm and 47.8–48.7 at 650 nm. Ten spot analyses of bowlesite give the average composition: Pt 56.85, Pd 0.02, Sn 34.03 and S 9.15, total 100.05 wt.%, corresponding to the empirical formula (Pt1.001Pd0.001)Σ1.002Sn0.997S1.001, based on 3 atoms per formula unit. The simplified formula is PtSnS. Due to the small size of bowlesite, the crystal structure was solved and refined from the powder X-ray-diffraction data of synthetic PtSnS. The calculated density is 10.06 g⋅cm–3. The mineral is orthorhombic, space group: Pca21 (#29) with a = 6.11511(10), b = 6.12383(10), c = 6.09667(11) Å, V = 228.31(1) Å3 and Z = 4. Bowlesite is isotypic with cobaltite, CoAsS. The origin of bowlesite is probably related to low-T exsolution of Pt–Sn phases from high-T sulfides crystallised from the sulfide melt. The mineral honours Dr. John Bowles (Manchester University, UK) for his contributions to ore mineralogy and mineral deposits related to mafic–ultramafic rocks.

APA, Harvard, Vancouver, ISO, and other styles

45

Walgenwitz, F., M. Pagel, G. Giroir, E. Merino, and D. Nahon. "Diagenesis of Cretaceous sandstone reservoirs of the South Gabon rift basin, West Africa; mineralogy, mass transfer, and thermal evolution; discussion and reply." Journal of Sedimentary Research 60, no. 3 (May 1, 1990): 471–80. http://dx.doi.org/10.1306/212f91c4-2b24-11d7-8648000102c1865d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Okereafor, Uchenna, Mamookho Makhatha, Lukhanyo Mekuto, and Vuyo Mavumengwana. "Gold Mine Tailings: A Potential Source of Silica Sand for Glass Making." Minerals 10, no. 5 (May 16, 2020): 448. http://dx.doi.org/10.3390/min10050448.

Full text

Abstract:

Mining of minerals such as gold, copper, and platinum has been one of several activities sustaining the economy of South Africa. However, the mining sector has contributed significantly to environmental contamination through the improper disposal of mine tailings which covers vast areas of land. Therefore, this study utilised a vitrification process to manufacture glass from gold mine tailings. X-ray fluorescence was used to determine the chemical composition of the tailings while X-ray diffraction was adopted for the mineralogy. The tailings were of granitic composition enriched in potentially toxic elements such as copper, cadmium, zinc, lead, arsenic, and chromium. A representative sample of gold mine wastes of sandy grain size was used in making the glass. Based on composition, the glass was formulated by adding an average 10.0 mass% of CaCO3 and 5.0 mass% of Na2CO3 to 35.0 mass% of SiO2, which resulted in the production of a green-coloured glass.

APA, Harvard, Vancouver, ISO, and other styles

47

van der Merwe, Frits, Fanus Viljoen, and Mike Knoper. "The mineralogy and mineral associations of platinum group elements and gold in the Platreef at Zwartfontein, Akanani Project, Northern Bushveld Complex, South Africa." Mineralogy and Petrology 106, no. 1-2 (August 1, 2012): 25–38. http://dx.doi.org/10.1007/s00710-012-0225-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Ozdemir, Seda, Toni Schulz, Christian Koeberl, Wolf Uwe Reimold, Tanja Mohr-Westheide, Desiree Hoehnel, and Ralf Thomas Schmitt. "Early Archean spherule layers from the Barberton Greenstone Belt, South Africa: Mineralogy and geochemistry of the spherule beds in the CT3 drill core." Meteoritics & Planetary Science 52, no. 12 (November 27, 2017): 2586–631. http://dx.doi.org/10.1111/maps.12998.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Büttner, S. H., S. Sherlock, L. Fryer, J. Lodge, T. Diale, R. Kazondunge, and P. Macey. "Controls of host rock mineralogy and H2O content on the nature of pseudotachylyte melts: Evidence from Pan-African faulting in the foreland of the Gariep Belt, South Africa." Tectonophysics 608 (November 2013): 552–75. http://dx.doi.org/10.1016/j.tecto.2013.08.024.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

van den Kerkhof, Alfons M., Graciela M. Sosa, Thomas Oberthür, Frank Melcher, Tobias Fusswinkel, Andreas Kronz, Klaus Simon, and István Dunkl. "The hydrothermal Waterberg platinum deposit, Mookgophong (Naboomspruit), South Africa. Part II: Quartz chemistry, fluid inclusions and geochronology." Mineralogical Magazine 82, no. 3 (April 12, 2018): 751–78. http://dx.doi.org/10.1180/mgm.2018.80.

Full text

Abstract:

AbstractThe historic Waterberg platinum deposit, ~15 km WNW of Mookgophong (formerly Naboomspruit), Limpopo Province, South Africa, is a rare fault-bound hydrothermal vein-type quartz-hematite-platinum-group mineralization. As a continuation of the geochemistry and ore mineralogy studies (Part I, Oberthür et al., 2018), this paper concentrates on the ore-bearing quartz and on the age constraints of ore formation. The state-of-the-art methods used include cathodoluminescence microscopy, electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of trace elements, stable isotope (δ18O) analysis and fluid-inclusion studies. U-Pb and (U-Th)/He radiometric age determination gave ages of 900–1075 Ma suggesting platinum-group element (PGE) mineralization as a result of upwelling fluids with connection to the Bushveld complex during Kibaran tectonic movements along the Thabazimbi–Murchison Lineament. Felsic fragments containing Qtz-1 were cemented by different quartz generations (Qtz-2 to Qtz-4) and enable the characterization of the changing physicochemical parameters during multistage mineralization and cooling. The PGE minerals are associated with the earliest hydrothermal stage represented by botryoidal radial-fibrous quartz aggregates (Qtz-2a) which formed on brecciated felsite. The other quartz types are essentially barren. Cathodoluminescence studies of quartz indicate very high Al, Fe and K concentrations as confirmed by EPMA and LA-ICP-MS, whereas Ti is always very low. The varying Al concentrations in the quartz mainly indicate pH fluctuations, the high Fe3+ points at high oxygen fugacity. Micro-inclusions of iron oxide are associated with Pt ore (Fe, Pt, Pd, Au, W, Sb, As), rutile, kaolinite and muscovite. The hydrothermal activity must have been characterized by low saline (<10 wt%) H2O–NaCl solutions. These fluids mixed with original high-saline NaCl ± CaCl2 ± CO2 brines in the brecciated felsite (Qtz-1). According to the quartz-hematite geothermometer the ore depositional temperatures were ~370–330°C (Qtz-2a), whereas the successive quartz veins formed during cooling towards ~295°C. The transport of PGE must have been facilitated by strongly oxidizing chloride complexes of relatively low salinity and moderate acidity.

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!