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Vredefort Granophyre

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Journal Article
Published: 01 December 2018
South African Journal of Geology (2018) 121 (4): 383–402.
...E. Kovaleva; M.S. Huber; F. Zaccarini Abstract Vredefort Granophyre dykes are generally considered to be a part of impact melt, which intruded downward from the melt sheet of the Vredefort impact structure (South Africa). This work reports enigmatic textural inhomogeneities found within the Daskop...
FIGURES | View All (12)
Journal Article
Journal: Geology
Published: 01 October 1996
Geology (1996) 24 (10): 913–916.
...Christian Koeberl; Wolf Uwe Reimold; Steven B. Shirey Abstract The origin of granophyric rock dikes (the Vredefort Granophyre) at the 2 Ga Vredefort structure in South Africa has been controversial. They have been interpreted as either impact melt or igneous intrusions. Most Vredefort Granophyre...
Journal Article
Journal: Geology
Published: 22 May 2019
Geology (2019) 47 (8): 691–694.
...Elizaveta Kovaleva; Dmitry A. Zamyatin; Gerlinde Habler Abstract The Vredefort impact structure, South Africa, is a 2.02 Ga deeply eroded meteorite scar that provides an opportunity to study large impact craters at their lower stratigraphic levels. A series of anomalous granophyre dikes in the core...
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Journal Article
Published: 01 March 2019
South African Journal of Geology (2019) 122 (1): 105–108.
... Society of South Africa 2019 Geological Society of South Africa The work by Kovaleva et al. (2018) deals with a narrow vein of pseudotachylitic breccia in a single granitic clast in a dike of Vredefort impact melt rock, the Vredefort Granophyre, on farm Daskop 1103. There are a number of issues...
FIGURES
Journal Article
Published: 01 March 2019
South African Journal of Geology (2019) 122 (1): 109–115.
... quarries), and in the yellow shade (Kopjeskraal, Eldorado and Rensburgsdrift farms). The clast on which our paper is centred comes from a well-known outcrop of the Vredefort granophyre on the farm Daskop, about 10 km southeast of the town of Parys ( Figure 1 ). This area is frequently visited...
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Journal Article
Published: 01 March 2018
South African Journal of Geology (2018) 121 (1): 51–68.
...E. Kovaleva; M.S. Huber; F. Roelofse; M. Tredoux; H. Praekelt Abstract A small, meta-granitic clast with a crosscutting microcrystalline vein was found enclosed within the Vredefort Granophyre. Semi-quantitative chemical analyses of the granophyre, granitic clast, and the vein were obtained in situ...
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Journal Article
Published: 01 June 1997
South African Journal of Geology (1997) 100 (2): 115–122.
...A. M. Therriault; W. U. Reimold; A. M. Reid Abstract The Vredefort impact structure contains a suite of granophyric dykes, referred to as the Vredefort Granophyre, occurring within and at the edge of the Archaean basement core. New whole-rock chemical analyses, together with previous data...
Series: GSA Special Papers
Published: 02 August 2021
DOI: 10.1130/2021.2550(09)
EISBN: 9780813795508
... (HSEs), Re-Os isotope data, as well as the first Se isotope and Se-Te elemental systematics are presented for the felsic and mafic varieties of Vredefort impact melt rock known as “Vredefort Granophyre.” In addition to the long-recognized “normal” (i.e., felsic, >66 wt% SiO 2 ) granophyre variety...
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Series: GSA Special Papers
Published: 02 August 2021
DOI: 10.1130/2021.2550(10)
EISBN: 9780813795508
...ABSTRACT ABSTRACT The Vredefort granophyre dikes have long been recognized as being derived from the now-eroded Vredefort melt sheet. One dike, in particular, the Daskop granophyre dike, is notable for a high abundance of lithic clasts derived from various stratigraphic levels. In this study...
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Journal Article
Published: 01 June 2013
South African Journal of Geology (2013) 116 (1): 101–118.
...C. HARRIS; D.S. FOURIE; A. FAGERENG Abstract We have determined the major element composition, δ 18 O and δD values, and water content of impact-related granophyre, and pseudotachylite, from various Vredefort Dome localities, aiming to constrain the mechanism of melt formation and the relationship...
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Journal Article
Published: 01 September 2016
South African Journal of Geology (2016) 119 (3): 453–472.
... of locally occurring granitoids and amphibolite. Harmonic least-squares mixing (HMX) calculations also do not indicate that additional components, such as a Vredefort Granophyre-like impact melt intrusive phase, contributed to the formation of these PTB. Absence of evidence (such as significant displacements...
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Image
Platinum group element (PGE) abundances of drill core samples. Filled circl...
Published: 01 May 2014
Figure 2. Platinum group element (PGE) abundances of drill core samples. Filled circles represent measured spherule-rich samples, open circles represent magmatic samples, and stars represent Vredefort granophyre. Linear regression of spherule-rich samples is plotted (m—slope of linear regression
Image
Plots of δ 18 O versus SiO 2 , Fe 2 O 3 , CaO and total alkalies for host-r...
Published: 01 June 2013
Figure 6 Plots of δ 18 O versus SiO 2 , Fe 2 O 3 , CaO and total alkalies for host-rock and pseudotachylite, and Vredefort Granophyre samples.
Image
Selected major element oxides and LOI versus SiO 2  for pseudotachylites, h...
Published: 01 June 2013
Figure 4 Selected major element oxides and LOI versus SiO 2 for pseudotachylites, host rocks, and Vredefort Granophyre (this work). For comparison, pseudotachylite, and host data from Lieger et al. (2011) are also plotted.
Journal Article
Journal: Geology
Published: 01 August 2019
Geology (2019) 47 (8): 799–800.
... granophyre, an unusual melt rock that occurs as a series of vertical dikes ( Therriault et al., 1996 ). Meteoritic Os uniquely identifies it as a product of impact melting ( Koeberl et al., 1996 ); however, the origin of the granophyre is controversial in the context of the formation of the Vredefort...
Image
Photographs of pseudotachylite bodies at ( a ) Leeukop – the height of the ...
Published: 01 June 2013
Figure 2 Photographs of pseudotachylite bodies at ( a ) Leeukop – the height of the outcrop is ~10 m, ( b ) Lesutoskraal – the width of the outcrop is ~1.8 m. Photomicrographs of the Vredefort granophyre (VC75) in ( c ) plane polarised light (PPL), and ( d ) crossed polars. Photograph of sample
Journal Article
Published: 01 December 2018
South African Journal of Geology (2018) 121 (4): 337–338.
... Supergroup, the first in the Bothaville area, and the second to the west near Leeudoringstad. The next two papers present new interpretations on the formation of two types of long-enigmatic melts that were produced by the Vredefort impact, the “Vredefort Granophyre” and pseudotachylite. The first...
Journal Article
Journal: Geology
Published: 01 May 2014
Geology (2014) 42 (5): 375–378.
...Figure 2. Platinum group element (PGE) abundances of drill core samples. Filled circles represent measured spherule-rich samples, open circles represent magmatic samples, and stars represent Vredefort granophyre. Linear regression of spherule-rich samples is plotted (m—slope of linear regression...
FIGURES
Journal Article
Published: 01 June 2012
South African Journal of Geology (2012) 115 (2): 251–255.
... in Vredefort Granophyre (impact melt rock), as reviewed e.g. by Gibson and Reimold (2008) . Mambane et al. (2011) set out to study ”…the spatial and temporal relationships between pseudotachylite veins and breccia systems… to constrain the relative chronology of crosscutting shock events” (p. 110 bottom...
Image
False-color Landsat Thermal Mapper satellite image of the <span class="search-highlight">Vredefort</span> Dome an...
Published: 01 March 2007
) . It is obviously not known what geometry the collapsed central uplift of the Vredefort impact structure would have had, but it can be assumed on the basis of the presence of the Granophyre dikes (compare Figures 12c and d) that the central peak was covered at least in part by impact melt. In comparison