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Ngwane Gneisses

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Journal Article
Published: 01 September 2021
South African Journal of Geology (2021) 124 (3): 761–782.
... during igneous zircon crystallization and subsequent compositional alteration. Four rock samples previously dated by SIMS U-Pb using zircon were selected: 3.56 Ga Ngwane Gneiss, 3.55 Ga Theespruit felsic metavolcanic, 3.50 Ga Steynsdorp Gneiss and 2.98 Ga Nhlangano Gneiss. LA-ICP-MS U-Pb zircon ages...
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U-Pb geochronological (common Pb uncorrected) and trace elemental data for ...
Published: 01 September 2021
Figure 6. U-Pb geochronological (common Pb uncorrected) and trace elemental data for 20 ablations of SW06-2 (3.56 Ga Ngwane Gneiss). Colors represent degrees of discordance (%).
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Geological map of the southeastern Kaapvaal craton showing distribution of ...
Published: 01 September 2012
(Commondale greenstone belt), NGB (Nondweni greenstone belt), NG (Ngwane Gneiss). Inset map shows location of the study area and the Kaapvaal craton in southern Africa.
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Cathodoluminescence (CL) images of selected zircons from samples BA06-2 (Th...
Published: 01 September 2021
Figure 2. Cathodoluminescence (CL) images of selected zircons from samples BA06-2 (Theespruit metavolcanic rock), BA06-3 (Steynsdorp Gneiss), SW06-2 (Ngwane Gneiss) and SW05-1 (Nhlangano Gneiss). Some grains show truncated zoning and embayments (e.g. SW06-2, upper right corner). Other
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Modeling of assimilation-fractional crystallization (AFC). Calculations wer...
Published: 13 February 2022
by the two ca. 3.2 Ga AGC granitoids. (b) AFC modeling for volcanic rocks in Th/Yb vs. Nb/Yb space using a harzburgitic 30% depleted mantle (DM) [ 74 ] batch melt and a ca. 3.5 Ga old Ngwane Gneiss (AGC 200) [ 20 ] as end members. The AFC modeling can reproduce most of the samples from our study and from
Journal Article
Published: 12 November 2014
Journal of the Geological Society (2015) 172 (1): 139–152.
... Gneiss Complex are the Ngwane Gneisses, the Dwalile Metamorphic Suite, the Tsawela Gneisses and the Usutu Granodiorite Suite ( Fig. 1 ; see Hunter et al . 1978 , 1984 ; Taylor et al . 2012 ). All components are in parallel tectonic contact owing to strong ductile deformation, so that the original...
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Journal Article
Journal: GSA Bulletin
Published: 01 March 2010
GSA Bulletin (2010) 122 (3-4): 408–429.
... gneiss complex is traditionally subdivided into three major units: the Ngwane gneiss, the Dwalile metamorphic suite, and the Tsawela gneiss ( Hunter, 1970 , 1979 ; Hunter et al., 1978 ; Jackson, 1984 ). The Ngwane gneiss consists of a series of multiply deformed tonalites, granodiorites, amphibolites...
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Journal Article
Published: 01 March 2021
South African Journal of Geology (2021) 124 (1): 37–52.
...., 1990 ), and within components of the Ngwane gneiss of the AGC ( Kroner et al., 1989 ; Zeh et al., 2009 ). Magmatism at ca . 3.45 Ga is recorded in emplacement of the Stolzburg pluton and the Theespruit granite. However, the main TTG intrusions in northern Barberton, the Kaap, Nelshoogte and Stentor...
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Journal Article
Journal: Lithosphere
Publisher: GSW
Published: 13 February 2022
Lithosphere (2022) 2022 (Special 8): 5729877.
... by the two ca. 3.2 Ga AGC granitoids. (b) AFC modeling for volcanic rocks in Th/Yb vs. Nb/Yb space using a harzburgitic 30% depleted mantle (DM) [ 74 ] batch melt and a ca. 3.5 Ga old Ngwane Gneiss (AGC 200) [ 20 ] as end members. The AFC modeling can reproduce most of the samples from our study and from...
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Journal Article
Journal: Geology
Published: 24 July 2023
Geology (2023) 51 (10): 919–923.
... Ga) Formations, Onverwacht Group ( Lowe and Byerly, 2007 ) ( Fig. 1A ). A 3.28 Ga granodiorite was collected from the Ngwane gneiss suite, Ancient Gneiss Complex (AGC) ( Kröner et al., 2019 ). The SGB (2.94–2.82 Ga) komatiite samples were from drill cores of the Hietahrju Ni-Cu-Co-PGE deposit...
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Journal Article
Published: 01 March 2003
South African Journal of Geology (2003) 106 (1): 35–40.
... of the sulfides were entrained to surface and deposited in fluid dynamic traps at the base of lava flows. Again, the lack of exposure prevents a satisfactory evaluation of this model. However, it appears that the oldest crustal fragments in the Kaapvaal craton (the Ngwane gneiss, ~3.64 Ga; Brandl and de Wit...
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Journal Article
Published: 01 December 2017
South African Journal of Geology (2017) 120 (4): 477–498.
... of the Ancient Gneiss Complex, and equated with the Ngwane Gneiss ( Hunter, 1993 ). Wilson (1982) defined it as high-grade semi-pelitic garnetiferous gneisses of likely Palaeo- to Mesoarchaean age. According to Wilson and Jackson (1988) , the Mahamba Gneiss is intimately associated with the Nhlangano Gneiss...
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Journal Article
Journal: Geology
Published: 26 July 2017
Geology (2017) 45 (9): 803–806.
...-magmatic Steynsdorp tonalitic gneisses. All detrital ages are also encompassed by the Ngwane Complex of the AGC. The only known occurrences of very sparse pre–3.6 Ga zircons are as xenocrysts in a granodiorite plug intrusive into the Komati Formation and in the Phophonyane shear zone in the AGC ( Compston...
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Journal Article
Published: 01 January 2013
Journal of the Geological Society (2013) 170 (1): 215–223.
... Onverwacht Group (Kromberg Formation: 3.334 ± 0.006 Ga; Mendon Formation: 3.298 ± 0.006 Ga) and from a granitoid sample (3.323 ± 0.007 Ga) of the Ngwane gneiss of Swaziland ( Byerly et al . 1996 ; Zeh et al . 2011 ). A similar age was also obtained from gneiss xenoliths in the Nelspruit ‘granite’ ( Kamo...
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Journal Article
Published: 01 September 2012
South African Journal of Geology (2012) 115 (3): 369–384.
... and amphibolites of the ca. 3.66 to 3.50 Ga Ngwane gneisses ( Kröner et al., 1989 ); (2) The ca. 3.55 Ga volcano-sedimentary rocks of the Dwalile Suite; (3) The 3.45 to 3.43 Ga Tsawela tonalite in southwest Swaziland ( Jackson, 1984 ; Kröner et al., 1989 ; Kröner and Tegtmeyer, 1994 ); and (4) ca. 3.23 to 3.22...
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Journal Article
Journal: GSA Bulletin
Published: 01 July 2012
GSA Bulletin (2012) 124 (7-8): 1191–1211.
... tectonometamorphic processes in general. The Ancient Gneiss Complex in Swaziland is an orthogneiss-dominated terrane composed of four main lithological units ( Fig. 1 ): finely interlayered and multiply deformed tonalites-trondhjemites-granodiorites (TTGs) of the ca. 3.66–3.50 Ga Ngwane gneiss ( Kröner et al...
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Journal Article
Published: 01 March 2021
South African Journal of Geology (2021) 124 (1): 111–140.
... the younger, but more juvenile TTGs in the region. Interestingly, three xenocrystic ( ca . 3.2 Ga) zircons from the Nelspruit Batholith have similar Hf isotope values to the Ngwane Gneiss in Swaziland, and it is likely that these represent entrained xenocrystic zircons from a source that was different...
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Journal Article
Published: 01 June 2004
South African Journal of Geology (2004) 107 (1-2): 13–32.
..., a better geochronological record of igneous lithologies is available than is the case for sedimentary units. The oldest dates obtained for southern Africa are recorded in detrital zircons from the Ngwane and Dwalile gneisses (Ancient Gneiss Complex) of Swaziland (3702 ± 1 Ma, 3683 ± 10 Ma and 3644...
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Journal Article
Published: 01 September 2012
South African Journal of Geology (2012) 115 (3): 259–282.
... (Commondale greenstone belt), NGB (Nondweni greenstone belt), NG (Ngwane Gneiss). Inset map shows location of the study area and the Kaapvaal craton in southern Africa. ...
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Series: Geological Society, London, Special Publications
Published: 01 January 2010
DOI: 10.1144/SP338.9
EISBN: 9781862395862
... magmatism related to subduction and accretion may not be the best analogue for long-lived greenstone belts such as Barberton in southern Africa, and the Pilbara in West Australia ( Van Kranendonk et al. 2007 ). Fig. 6. ( a ) Banded early Archaean Ngwane gneiss from Ancient Gneiss Complex, Swaziland...
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