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![Simplified geological map of southern Africa, with the Grunehogna Craton (Dronning Maud Land, Antarctica) in pre-drift position. Outcrop of cover sequences mainly after South African Committee for Stratigraphy (1980). Late Palaeozoic-early Mesoproterozoic cover sequences of the Karoo and Kalahari basins have been given a semi-transparent signature to show the major features of the underlying, Precambrian crust. Abbreviations: KVC: Kaapvaal Craton, ZC: Zimbabwe Craton, CG: Grunehogna Craton, CoC: Congo Craton, Rh: Rehoboth province, NNB: Namaqua-Natal Belt. Terranes in the Namaqua Sector of the Namaqua-Natal Belt: Kh: Kheis Province, Ka: Kaaien Domain, Kk: Kakamas Domain, R: Richtersveld Subprovince, B: Bushmanland Subprovince, A: Areachap Domain. In the legend: Gr: Group, Spgr / spgr: Supergroup.]()
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![Napier and Grunehogna cratons (Antarctica) on the Moho map.]()
![Western Dronning Maud Land shown in the context of the East African–Antarctic Orogen in a Gondwana supercontinent configuration (modified after Jacobs et al. 1993, 1998, 2003, Jacobs et al. 2008a,b). (a) Major Pan-African crustal reworking of the entire Maud Belt and Kaapvaal–Grunehogna Craton margin with the Pencksökket–Jutulstraumen Discontinuity representing a major Pan-African thrust on the southeastern edge of the Kaapvaal–Grunehogna Craton margin. (b) Preferred P–T–t path for southeastern Kaapvaal–Grunehogna Craton margin including the western Maud Belt (western H.U. Sverdrupfjella) shown in red, compared with P–T constraints in the eastern H.U. Sverdrupjella of Board et al. (2005). SR, Shackleton Range (Shackelton 1996); HF, Heimefrontfjella; SF, Sverdrupfjella; KW, Kirwenveggen; GF, Gjelsvikfjella; CDML, central Dronning Maud Land; SL, Sri Lanka; NNP, Namaqua–Natal Province or Belt; FMA, Foster Magnetic Anomaly; PJD, Pencksökket–Jutulstraumen Discontinuity, GC, Grunehogna Craton. LHB = Lutzow-Holm Block, YB = Yamato-Belgica Block, SD = Sør Rondane, HSZ = Heimefront Shear Zone, C = Coats Land, FM = Falkland Islands Microplate.]()
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![A new geodynamic tectonothermal model depicting the crustal evolution of western Dronning Maud Land. It is proposed herein that the western part of the Maud Belt initially formed part of the Archaean Kaapvaal–Grunehogna Craton (KGC) margin, prior to major Grenville-aged and Pan-African age high-grade tectonothermal metamorphism. It is shown that during Gondwana assembly, the entire southeasternmost Kaapvaal–Grunehogna Craton margin represented by the western H.U. Sverdrupfjella at Straumsvola experienced major tectonothermal reworking at upper amphibolite-facies conditions. Tectonic juxtaposition of the eastern H.U. Sverdrupjella (EHUS) crustal segment onto the western H.U. Sverdrupfjella (WHUS; craton margin) occurred during late Pan-African times (c. 500 Ma), during diachronous east–west Pan-African accretion and tectonism. Earliest peak metamorphic conditions at c. 565 ± 11 Ma in the eastern H.U. Sverdrupjella crustal segment predated peak upper amphibolite-facies metamorphism in the easternmost Kaapvaal–Grunehogna Craton margin (i.e. western H.U. Sverdrupfjella) recorded at c. 500 Ma. This more complex Pan-African model for western Dronning Maud Land is in sharp contrast to previously suggested crustal evolution models proposing a Namaqua–Natal–Maud Belt juvenile volcanic arc that experienced only late Mesoproterozoic granulite-facies metamorphism in the western Maud Belt (see Jacobs et al. 1993, 1996, 2003, 2008a,b; Grantham et al. 1995; Groenewald et al. 1995). PJD, Pencksökket–Jutulstraumen Discontinuity. OC = Other craton, EAC = East Antarctic Craton.]()
![Location map of rock outcrops in western Dronning Maud Land (Antarctica) from Vestfjella to H.U. Svedrupfjella, including the location of the Jutustraumen and Pencksökket subglacial troughs. The lower right inset is a pre-break-up Gondwana reconstruction of Africa and Antarctica showing the extent of the Kaapvaal-Grunehogna craton and the outcrop of Early-Middle Jurassic age Karoo igneous rocks (after Luttinen and Furnes, 2000). ODS, Okavango dyke swarm; SRBF, Sabi River Basalt Formation; RRDS, Rooi Rand dyke swarm (after Riley et al., 2005). The region of western Dronning Muad Land shown is situated on the boundary between the Grunehogna craton and the Maud Province in the reconstruction.]()
![(a) Simplified geological map of southern Africa, with the Grunehogna Craton (Dronning Maud Land, Antarctica) in pre-drift position. Outcrop of cover sequences mainly after South African Committee for Stratigraphy (1980) with additional data from Schlüter (2006). Late Palaeozoic - Mesozoic deposits of the Karoo Supergroup have been given a semi-transparent signature to show the major features of the underlying Precambrian crust. Abbreviations: KVC=Kaapvaal Craton, ZC=Zimbabwe Craton, CG=Grunehogna Craton, CoC=Congo Craton, Rh=Rehoboth province, NNB=Namaqua-Natal Belt. T=Transvaal Basin, GW=Griqualand-West Basin, W=Waterberg and Nylstroom basins. O (outlined by dotted line)= Okwa Block or Terrane (Oriolo and Becker, 2018). OBC=Okwa Basement Complex, OGr=Okwa Group. B and R=Bushmanland and Richtersveld subprovinces of the Namaqua-Natal Belt. The limit of Archaean and Palaeoproterozoic crust corresponds to the extent of the Kalahari Craton at mid-Proterozoic time proposed by Jacobs et al. (2008). In the legend: Gr.=Group, SGr.=Supergroup. The position of sample DF06-40 is from Foster et al. (2015). The position of Figure 1b is indicated.(b) Simplified outcrop map of part of the Okwa Valley from Aldiss (1988). Formation names are as in Ramokate et al. (2000). The inset in the upper left part of the figure is a magnification of the locality that was sampled, with orientation of bedding planes according to Aldiss (1988).]()
![Location of the study area in a Gondwana reconstruction after Lawver and Scotese (1987), Grunow et al. (1996), Shackleton (1996), and Jacobs et al. (1998) with major Pan-African belts indicated. African geology after Hartnady et al. (1985) and Porada (1989). Heimefrontfjella is part of an extensive, several-thousand-kilometer-long, ca. 1.1-Ga mobile belt that rims the Zimbabwe-Kaapvaal-Grunehogna craton. Heimefrontfjella marks the western boundary of intense Pan-African (at ca. 500 Ma) tectono-thermal reworking. Possible Pan-African suture zones after (1) Shackleton (1996) and (2) Grunow et al. (1996). CDML, central Dronning Maud Land; C, Coats Land; E, Ellsworth Mountains; FCB, Filchner Crustal Block; FM, Falkland Microplate; G, Grunehogna craton; H, Haag Nunataks; K, Kirwanveggen; LH, Lützow Holm Bay; MB, Mwembeshi Shear Zone; Na-Na, Namaqua-Natal Belt; PB, Prydz Bay; R, Richtersveld craton; M, Madagascar; Moz, Mozambique Belt; S, Sverdrupfjella; Sa, Saldania Belt; SL, Sri Lanka; Sø, Sør Rondane; SR, Shackleton Range; WDML, western Dronning Maud Land; Z, Zambezi Belt.]()
![40Ar/39Ar hornblende ice-rafted debris maps of East Antarctica with pie charts showing the distribution of thermochronologic ages by site location along with known onshore ages (modified from Pierce et al., 2014). The color scale corresponds to 100 m.y. increments of time. GC—Grunehogna craton, G—Gjelsvikfjella, H—Haag Nunatak, HU—H.U. Sverdrupfjella, K—Kirwanveggan.]()
![Tectonic schematic interpretation of the relationships between the Grunehogna Craton, the Maud Belt and the EAO Namuno-nappe structure. Single-headed blue arrows reflect senses of shear between different blocks related to D1. Double-headed red arrows reflect inferred senses of shear between different blocks related to D2/3. The types of structures observed with inferred deformational age are shown, as well as relative schematic location in the section of geographic localities reported in the text.]()
![Tectonic map of western Dronning Maud Land (modified after Board et al. 2005) showing an inferred (this study) major Pan-African thrust between the Grunehogna Craton and the Maud Belt. Sample localities at Nashornkalvane South (072°19.06S, 001°57.46W) and the outcrop near Straumsvola (072°09.775, 000°14.52W) are shown (map of Straumsvola nunatak in the inset is after Harris & Grantham 1993). HSZ, Heimefront Shear Zone; PJD, Pencksökket–Jutulstraumen Discontinuity.]()
![(a) Simplified map showing the best estimate of true distance between the westernmost Maud Belt and easternmost Grunehogna Craton margin (red arrow). The light green and orange shaded areas mark estimates of the inferred subglacial geology of the Grunhogna Craton and the Maud Belt, respectively, on map. (b) The inferred or reconstructed subglacial bedrock topography across the Pencksökket–Jutulstraumen Discontinuity along the red arrow in (a) using the seismic data of Näslund (1998) and Melvold & Rolstad (2000) and the new petrological data presented in the current study. Using the inferred subglacial metamorphic and structural geology, it is proposed herein that the Pencksökket–Jutulstraumen Discontinuity represents a major Pan-African thrust zone, which was reactivated by normal faulting to form a graben during Gondwana break-up. JPFZ = Jutulstraumen-Pencksokket Fault Zone.]()
![Summary diagram showing P–T constraints on metamorphic conditions at Nashornkalvane (eastern Grunehogna Craton) and Straumsvola (W.H.U.S., western H.U. Sverdrupfjella; western Maud Belt) compared with those from eastern Maud Belt (eastern H.U. Sverdrupfjella; Board et al. 2005). A metamorphic hiatus of T = 350–400°C and P c. 0.6 GPa across the Jutulstraumen glacier should be noted. Granulite-facies conditions are derived from mafic boudins after Groenewald & Hunter (1991) and Groenewald et al. (1995). Aluminosilicate triple point is after Bohlen et al. (1991). Reactions (13), (14) and (15) are from Pattison (2003) calculated on the basis of a pargasite composition with XMg = 0.5. Reaction (16) is the approximate position of the wet tonalite solidus (Piwinskii 1968; Johannes 1978; Wyllie & Wolf 1993).]()
![Geological map of the Sistefjell group of nunataks. The shape of the Sistefjell syenite is interpreted from aeromagnetic data (Corner 1994). The margin of the Sistefjell quartz syenite is only observed on the south side of Sistenup, and the outline of the complex is schematic, although there are some geological reasons for drawing the margin close to the south side of Sistefjell (see text). The inset map shows their position in western Dronning Maud Land. The Jutulstraumen-Pencksokket glaciers separate the Grunehogna Craton in the west from the Maud Belt. Note that H.U. Sverdrupfjella refers to the mountain range to the west of the Jutulstraumen Glacier; the Sverdrupfjella Group comprises rocks from both the H.U. Sverdrupfjella and the Kirwanveggen mountain range to the east of the Jutulstraumen. The lower diagram shows the field relations of dykes and sills, which intrude the syenite as, exposed in the north face of Sistefjell directly below the summit.]()
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![Figure 11.]()
![Figure 9.]()
![(a) Simplified map of eastern South Africa showing the main geological provinces and the localities sampled for this study. JJV-AF5, JJV-AF6 and JJV-AF7 are samples of the Karoo Vryheid Formation from Veevers & Saeed (2007); in subsequent diagrams, detrital zircons from these samples have been pooled and identified as ‘VRY’. The inset shows the outline of South Africa with the present-day outcrop area of the Karoo Supergroup (shaded) and the drainage basin of the Orange River with its Vaal tributary (limited by dashed line). The Orange River drains into the Atlantic Ocean at the South Africa–Namibia border in the extreme left of the inset map. (b) Pre-breakup western Gondwana (Jacobs et al. 2003; Torsvik & Cocks 2011, and references therein). The Archaean Kaapvaal Craton (KC) extends into Antarctica as the Grunehogna Craton, and is surrounded by Proterozoic and Phanerozoic mobile belts: Namaqua–Natal Belt (NNB, Mesoproterozoic), East African orogen (EAO, Neoproterozoic) and Cape Fold Belt (CFB, Phanerozoic), which is part of the larger Gondwanide Orogen (e.g. Milani & De Wit 2008). The maximum outline of late Palaeozoic (Carboniferous–Permian) sedimentary basins (from Smith et al. 1993) is indicated by a bold dashed line. Microplates: F, Falkland Plateau; EW, Ellsworth–Whitmore Mountains (part of present-day West Antarctica); AP, Antarctic Peninsula; P, Patagonia. (c) Schematic profiles of present-day geology of eastern South Africa. Not to scale in either vertical or horizontal direction. The main profile illustrates general features of geology in an east–west section from Lesotho to Richards Bay, the lower section is a generalized section perpendicular to the coast at Durban, and the upper profile illustrates basement–cover relationships in any of several basement windows at the southern margin of the Kaapvaal Craton.]()
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Simplified geological map of southern Africa, with the Grunehogna Craton (D... Available to Purchase
in Detrital zircon in sandstones from the Palaeoproterozoic Waterberg and Nylstroom basins, South Africa: Provenance and recycling
> South African Journal of Geology
Published: 01 March 2019
Figure 1. Simplified geological map of southern Africa, with the Grunehogna Craton (Dronning Maud Land, Antarctica) in pre-drift position. Outcrop of cover sequences mainly after South African Committee for Stratigraphy (1980). Late Palaeozoic-early Mesoproterozoic cover sequences of the Karoo
Journal Article
Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica Available to Purchase
Journal: Journal of the Geological Society
Publisher: Geological Society of London
Published: 21 May 2015
Journal of the Geological Society (2015) 172 (4): 499–518.
...Eugene G. Grosch; Hartwig E. Frimmel; Tamer Abu-Alam; Jan Košler Abstract A petrological and metamorphic comparison of Mesoproterozoic metabasic rocks was conducted on the eastern margin of the Archaean Kaapvaal–Grunehogna Craton and the adjacent westernmost Maud Belt (western H.U. Sverdrupfjella...
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Napier and Grunehogna cratons (Antarctica) on the Moho map. Available to Purchase
in Crustal structure and properties of Archean cratons of Gondwanaland: similarity and difference
> Russian Geology and Geophysics
Published: 01 May 2018
Fig. 7. Napier and Grunehogna cratons (Antarctica) on the Moho map.
Image
Western Dronning Maud Land shown in the context of the East African–Antarct... Available to Purchase
in Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica
> Journal of the Geological Society
Published: 21 May 2015
and Kaapvaal–Grunehogna Craton margin with the Pencksökket–Jutulstraumen Discontinuity representing a major Pan-African thrust on the southeastern edge of the Kaapvaal–Grunehogna Craton margin. ( b ) Preferred P – T – t path for southeastern Kaapvaal–Grunehogna Craton margin including the western Maud Belt
Journal Article
Geochemistry and tectonic setting of mafic rocks in western Dronning Maud Land, East Antarctica: implications for the geodynamic evolution of the Proterozoic Maud Belt Available to Purchase
Journal: Journal of the Geological Society
Publisher: Geological Society of London
Published: 01 March 2007
Journal of the Geological Society (2007) 164 (2): 465–475.
..., was on the southeastern margin of the Kaapvaal–Grunehogna Craton. The protoliths of Group 2 amphibolites are attributed to the 1110 Ma Borgmassivet–Umkondo thermal event on the basis of comparable Nd model ages and trace element distributions. Group 3 amphibolite protoliths are characterized by mid-ocean ridge basalt...
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Journal Article
Detrital zircon U–Pb ages of the Palaeozoic Natal Group and Msikaba Formation, Kwazulu-Natal, South Africa: provenance areas in context of Gondwana Available to Purchase
Journal: Geological Magazine
Publisher: Cambridge University Press
Published: 07 August 2015
Geological Magazine (2016) 153 (3): 460–486.
... of detritus. The Namaqua–Natal Metamorphic Complex is suggested as a possible source of minor late Mesoproterozoic-aged detritus. Minor populations of Archean and Palaeoproterozoic zircons were likely sourced from the Kaapvaal and Grunehogna Cratons. Post-orogenic Cambrian – Lower Ordovician granitoids...
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A new geodynamic tectonothermal model depicting the crustal evolution of we... Available to Purchase
in Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica
> Journal of the Geological Society
Published: 21 May 2015
Fig. 11. A new geodynamic tectonothermal model depicting the crustal evolution of western Dronning Maud Land. It is proposed herein that the western part of the Maud Belt initially formed part of the Archaean Kaapvaal–Grunehogna Craton (KGC) margin, prior to major Grenville-aged and Pan-African
Image
Location map of rock outcrops in western Dronning Maud Land (Antarctica) fr... Available to Purchase
in The geochemistry of Middle Jurassic dykes associated with the Straumsvola-Tvora alkaline plutons, Dronning Maud Land, Antarctica and their association with the Karoo large igneous province
> Mineralogical Magazine
Published: 01 April 2009
showing the extent of the Kaapvaal-Grunehogna craton and the outcrop of Early-Middle Jurassic age Karoo igneous rocks (after Luttinen and Furnes, 2000 ). ODS, Okavango dyke swarm; SRBF, Sabi River Basalt Formation; RRDS, Rooi Rand dyke swarm (after Riley et al ., 2005 ). The region of western Dronning
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( a ) Simplified geological map of southern Africa, with the Grunehogna C... Available to Purchase
in Enigmatic provenance signature of sandstone from the Okwa Group, Botswana
> South African Journal of Geology
Published: 01 September 2020
Figure 1. ( a ) Simplified geological map of southern Africa, with the Grunehogna Craton (Dronning Maud Land, Antarctica) in pre-drift position. Outcrop of cover sequences mainly after South African Committee for Stratigraphy (1980) with additional data from Schlüter ( 2006 ). Late Palaeozoic
Image
Location of the study area in a Gondwana reconstruction after Lawver and Sc... Available to Purchase
in Grenville-Age versus Pan-African Magnetic Anomaly Imprints in Western Dronning Maud Land, East Antarctica
> The Journal of Geology
Published: 01 January 2001
is part of an extensive, several-thousand-kilometer-long, ca. 1.1-Ga mobile belt that rims the Zimbabwe-Kaapvaal-Grunehogna craton. Heimefrontfjella marks the western boundary of intense Pan-African (at ca. 500 Ma) tectono-thermal reworking. Possible Pan-African suture zones after ( 1 ) Shackleton ( 1996
Image
40 Ar/ 39 Ar hornblende ice-rafted debris maps of East Antarctica with pie ... Open Access
Published: 01 July 2020
—Grunehogna craton, G—Gjelsvikfjella, H—Haag Nunatak, HU—H.U. Sverdrupfjella, K—Kirwanveggan.
Image
Tectonic schematic interpretation of the relationships between the Grunehog... Available to Purchase
in The structural evolution of the Straumsnutane and western Sverdrupfjella areas, western Dronning Maud Land, Antarctica: implications for the amalgamation of Gondwana
> Geological Magazine
Published: 10 February 2020
Fig. 16. Tectonic schematic interpretation of the relationships between the Grunehogna Craton, the Maud Belt and the EAO Namuno-nappe structure. Single-headed blue arrows reflect senses of shear between different blocks related to D 1 . Double-headed red arrows reflect inferred senses of shear
Image
Tectonic map of western Dronning Maud Land (modified after Board et al . ... Available to Purchase
in Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica
> Journal of the Geological Society
Published: 21 May 2015
Fig. 1. Tectonic map of western Dronning Maud Land (modified after Board et al . 2005 ) showing an inferred (this study) major Pan-African thrust between the Grunehogna Craton and the Maud Belt. Sample localities at Nashornkalvane South (072°19.06S, 001°57.46W) and the outcrop near Straumsvola
Image
( a ) Simplified map showing the best estimate of true distance between the... Available to Purchase
in Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica
> Journal of the Geological Society
Published: 21 May 2015
Fig. 10. ( a ) Simplified map showing the best estimate of true distance between the westernmost Maud Belt and easternmost Grunehogna Craton margin (red arrow). The light green and orange shaded areas mark estimates of the inferred subglacial geology of the Grunhogna Craton and the Maud Belt
Image
Summary diagram showing P – T constraints on metamorphic conditions at Na... Available to Purchase
in Metamorphic and age constraints on crustal reworking in the western H.U. Sverdrupfjella: implications for the evolution of western Dronning Maud Land, Antarctica
> Journal of the Geological Society
Published: 21 May 2015
Fig. 9. Summary diagram showing P – T constraints on metamorphic conditions at Nashornkalvane (eastern Grunehogna Craton) and Straumsvola (W.H.U.S., western H.U. Sverdrupfjella; western Maud Belt) compared with those from eastern Maud Belt (eastern H.U. Sverdrupfjella; Board et al . 2005
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Geological map of the Sistefjell group of nunataks. The shape of the Sistef... Available to Purchase
in Petrogenesis of the Mesozoic Sistefjell syenite intrusion, Dronning Maud Land, Antarctica and surrounding low-δ 18 O lavas
> South African Journal of Geology
Published: 01 September 2002
, although there are some geological reasons for drawing the margin close to the south side of Sistefjell (see text). The inset map shows their position in western Dronning Maud Land. The Jutulstraumen-Pencksokket glaciers separate the Grunehogna Craton in the west from the Maud Belt. Note that H.U
Book Chapter
The Mutare–Fingeren dyke swarm: the enigma of the Kalahari Craton's exit from supercontinent Rodinia Open Access
Series: Geological Society, London, Special Publications
Publisher: Geological Society of London
Published: 03 January 2024
DOI: 10.1144/SP537-2022-206
EISBN: 9781786205032
... ; Rapela et al. 2016 ; Hodgin et al. 2021 ). Kalahari is also usually reconstructed with the Grunehogna Craton and the Meso- to Neoproterozoic segments of the Maud Belt. The Grunehogna Craton, together with the Meso- to Neoproterozoic Maud Belt, has long been considered either as a fragment...
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Proposed depositional model for the Natal Group and Msikaba Formation. (a) ... Available to Purchase
in Detrital zircon U–Pb ages of the Palaeozoic Natal Group and Msikaba Formation, Kwazulu-Natal, South Africa: provenance areas in context of Gondwana
> Geological Magazine
Published: 07 August 2015
are
derived, in part, from the Kaapvaal and Grunehogna cratons and deposited in a
NE–SW-aligned depositional trough. (b) Deposition of the upper Durban and
Mariannhill formations during Ordovician – Early Devonian time. Cratons rapidly
become covered
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Geochronological reconstruction of the geology of east Gondwana at the time... Available to Purchase
in Detrital zircon U–Pb ages of the Palaeozoic Natal Group and Msikaba Formation, Kwazulu-Natal, South Africa: provenance areas in context of Gondwana
> Geological Magazine
Published: 07 August 2015
Dellgado Nappes; CMC – Cape Meredith Complex; CSG –
Cape Supergroup; DC – Dharwar Craton; EAC – East Antarctica Craton; EG – Eastern
Granulites; GC – Grunehogna Craton; GF – Gjelsvikfjella; HC – Highland Complex; HF –
Heimefrontfjella; I – Itremo (Madagascar
Image
( a ) Simplified map of eastern South Africa showing the main geological pr... Available to Purchase
in U–Pb and Lu–Hf zircon data in young sediments reflect sedimentary recycling in eastern South Africa
> Journal of the Geological Society
Published: 27 October 2015
at the South Africa–Namibia border in the extreme left of the inset map. ( b ) Pre-breakup western Gondwana ( Jacobs et al . 2003 ; Torsvik & Cocks 2011 , and references therein). The Archaean Kaapvaal Craton (KC) extends into Antarctica as the Grunehogna Craton, and is surrounded by Proterozoic
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