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Witkop Formation

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Field photograph of deformed pillow basalt from the <span class="search-highlight">Witkop</span> <span class="search-highlight">Formation</span>. Light...
Published: 01 September 2012
Figure 4 Field photograph of deformed pillow basalt from the Witkop Formation. Light-grey domains represent stretched pillow cores and dark-grey bands represent pillow rims. The dark-grey bands are rich in garnet porphyroblasts.
Journal Article
Published: 01 September 2012
South African Journal of Geology (2012) 115 (3): 259–282.
...Figure 4 Field photograph of deformed pillow basalt from the Witkop Formation. Light-grey domains represent stretched pillow cores and dark-grey bands represent pillow rims. The dark-grey bands are rich in garnet porphyroblasts. ...
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Image
Chondrite-normalized REE plots of pillow cores in comparison with a sample ...
Published: 01 September 2012
Figure 6 Chondrite-normalized REE plots of pillow cores in comparison with a sample of basaltic andesite from the Witkop Formation (filled symbol) as reported in Hofmann and Wilson (2007) .
Image
Geological map of the Nondweni greenstone belt showing the distribution of ...
Published: 01 September 2012
Figure 2 Geological map of the Nondweni greenstone belt showing the distribution of the Magongolozi, Toggekry and Witkop formations and their contact relationship with the intrusive Mvunyana granodiorite (a modified after Wilson and Versfeld, 1994a ).
Image
Outcrop photographs showing the few reported occurrences of Palaeoarchaean ...
Published: 01 March 2021
Formation, Barberton greenstone belt. ( C ) and ( D ) Decimetric domical stromatolites from the ~3.4 Ga Witkop Formation, Nondweni greenstone belt. All stromatolites show a moderate degree of inheritance. (A) from de Wit et al. ( 1982 ); (B) from Lowe and Byerly ( 2018 ); (C and D from Wilson and Versfeld
Image
( a ) The <span class="search-highlight">Witkop</span> III hydrothermal vent complex comprises an outer zone with...
Published: 01 July 2006
Fig. 5.  ( a ) The Witkop III hydrothermal vent complex comprises an outer zone with structurally modified Clarens strata, and an inner zone with abundant sediment breccia. The whole Clarens Formation is exposed in the area, and the Drakensberg Group basalts are seen in the background. Car
Image
( a ) Geological map of the <span class="search-highlight">Witkop</span> III hydrothermal vent complex. Three com...
Published: 01 July 2006
of the Witkop III area, showing sedimentary strata from the Elliot and Clarens formations unaffected by the vent complex formation (left), surface logs of breccias and sandstone (logs A–C), and a log of the borehole. The ‘background log’ is constructed based on exposures between the Elliot Formation (exposed
Journal Article
Published: 01 July 2006
Journal of the Geological Society (2006) 163 (4): 671–682.
...Fig. 5.  ( a ) The Witkop III hydrothermal vent complex comprises an outer zone with structurally modified Clarens strata, and an inner zone with abundant sediment breccia. The whole Clarens Formation is exposed in the area, and the Drakensberg Group basalts are seen in the background. Car...
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Journal Article
Published: 01 March 2007
Journal of the Geological Society (2007) 164 (2): 477–479.
..., particularly concerning two vent complexes known as Witkop II and Witkop III. One of us (B.E.L.) had barely initiated a study of the Stormberg diatremes when he left South Africa to accept a faculty position in Louisiana in 1977, and the project was not continued. However, the Svensen paper reminded us...
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SEM backscatter images from Clarens <span class="search-highlight">Formation</span> sandstone surrounding the Wit...
Published: 01 July 2006
Fig. 8.  SEM backscatter images from Clarens Formation sandstone surrounding the Witkop III complex. ( a ) Possible volcanic material (glass) now altered to chlorite and illite. The texture differs from anything seen in the sediment breccia from the hydrothermal vent complexes. ( b ) Zeolite
Journal Article
Published: 01 June 2019
South African Journal of Geology (2019) 122 (2): 187–220.
... ). A very prominent and thick, medium- to coarse-grained meta-quartz arenite forms the top of this succession in the closure of the Karos anticline (section S4 and localities, 10 and 15 in Figure 4 ). It is defined as the Witkop member of the Skurweberg formation and can be traced over approximately 80...
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Journal Article
Published: 01 September 2006
South African Journal of Geology (2006) 109 (3): 341–352.
.... The currently prevailing ore deposit model for the formation of these pegmatites regards the pegmatite body as the final stage of crystallization of a cooling granitic magma ( Cerny, 1998a ). Recent studies suggest that crystallization of the pegmatite body happens at unexpectedly fast rates during under...
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Journal Article
Published: 01 March 2021
South African Journal of Geology (2021) 124 (1): 225–252.
... Formation, Barberton greenstone belt. ( C ) and ( D ) Decimetric domical stromatolites from the ~3.4 Ga Witkop Formation, Nondweni greenstone belt. All stromatolites show a moderate degree of inheritance. (A) from de Wit et al. ( 1982 ); (B) from Lowe and Byerly ( 2018 ); (C and D from Wilson and Versfeld...
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Journal Article
Published: 01 December 2002
South African Journal of Geology (2002) 105 (4): 381–400.
... provides new lithofacies descriptions and suggests formation boundary positions for the upper Campbellrand Subgroup stratigraphy exposed by the open pit and underground tunnel network at the mine. The Klippan Formation lagoonal facies, the Kogelbeen Formation subtidal facies and the Gamohaan Formation...
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Journal Article
Journal: Elements
Published: 01 June 2010
Elements (2010) 6 (3): 179–182.
... into the atmosphere. When sedimentary rocks are heated by magma, decomposition of organic matter, mineral dehydration (generating H 2 O and CO 2 ), and pore fluid expansion or boiling occur on a timescale of years. The resulting overpressure can lead to hydrofracturing and the formation of breccia pipes...
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Journal Article
Published: 11 July 2022
Journal of Sedimentary Research (2022) 92 (7): 619–634.
... relief ( Allwood et al. 2006 , 2009 ), and the overall characteristics are similar to the shore platform-boulder facies association reported here. A second Archean (3.41 Ga) example is in the Witkop Formation from Nondweni, Kaapvaal Craton, KwaZulu–Natal, South Africa ( Wilson and Versfeld 1994 ; Xie...
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Journal Article
Published: 01 September 2020
South African Journal of Geology (2020) 123 (3): 263–276.
...., 2010 ; Xie et al., 2012 ). In general, greenstone belts consist predominantly of basalt ( Sylvester et al., 1997 ), representing the most likely protolith for the amphibolite, in agreement with its chemical composition. The ca. 3.41 Ga Witkop Formation of the Nondweni greenstone belt is a mafic...
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Journal Article
Published: 01 December 2004
South African Journal of Geology (2004) 107 (4): 559–576.
... greenschists and siliceous oolithic sediments have also been recognised. In the basal portion of the Witkop Formation in the Patsoana area, various quartzite types have been distinguished such as black and white banded varieties, finely-banded greenish and beige varieties as well as massive sulphide-bearing...
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Journal Article
Published: 01 September 2010
South African Journal of Geology (2010) 113 (2): 195–228.
... of England et al., 2002 ). Composite lithoclasts can be transported to the sediment via a number of processes, such as storms, volcanic eruptions, debris flows and intraformational reworking. In the Versterkop and Witkop Members of the Brixton Formation, shale clasts commonly contain small euhedral pyrite...
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Journal Article
Published: 01 December 2005
South African Journal of Geology (2005) 108 (4): 465–492.
... is recorded by clastic fluvial and limnic sedimentary rocks of the Billstein formation with only minor if any felsic pyroclastic activity. Intrusive porphyry dykes constrain a minimum age of 1210 +/− 7 Ma. The second stage (Nückopf, Langberg formations, Kartatsaus member), lasting from at least 1.23 Ga...
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