Vredefort - Hypervelocity Impact Crater

Alternate Names N/A
Coordinates 27° 0' 50" S; 27° 29' 44" E
Notes
  1. ~120 km SSW of Johannesburg, in the Republic of South Africa.
Country South Africa
Region Free State
Date Confirmed 1961
Notes
  1. Confirmed by the presence of shatter cones "in the sedimentary collar of the Vredefort Ring" (Hargraves, 1961).
Buried? No
Notes
  1. The southern area of the core and collar rocks is obscured by younger Karroo Super group sediments (Lilly, 1981).
Drilled? Yes
Notes
  1. Deep drilling below the Karroo System has confirmed the essential circular shape of the concealed portion of the ring; drilling penetrated granite of the central uplift and overturned metasediments of the collar (Borchers, 1961).
Target Type Crystalline
Notes
  1. Archean granite and gneisses and Proterozoic metasediments and volcanics (Manton, 1965).
Sub-Type Gneiss, Metasedimentary, Volcanics, Granite
Apparent Crater Diameter (km) 300 km
Age (Ma) 2023 ± 4
Notes :
  1. 2023 ± 4 Ma determined by U-Pb of shocked zircons in pseudotachylites and granophyre dykes (Kamo et al., 1996).

Method :
  1. U-Pb
Impactor Type Unknown

Advanced Data Fields

Notes

Local Language
N/A
Erosion
7
  1. Erosion as removed all traces of the ejecta rim and crater-fill products, exposing the deformed base (Diez, 1961). Some 8 km of erosion estimated (Therriault et al., 1993).
Final Rim Diameter
Unknown
Apparent Rim Diameter
300 km
  1. Apparent diameter estimate is 250-300 km (Grieve et al., 2008). Structural uplift is corrected for erosion (Hart et al., 1991). Diameter of structural uplift is according to (Therriault et al., 1993) and is a minimum. Estimated diameter (Wilshire, 1971) (Hart et al., 1991) (Therriault et al., 1993).
Rim Reliability Index
3
  1. Central uplift core of Archean granite, ~44 km in diameter, a surrounding collar of upturned and overturned Proterozoic metasedimentary strata and igneous rocks, ~20 km, wide and an outlying concentric syclinorium, ~28 km wide (Wilshire, 1971). The central, structurally uplifted area ~80-90 km in diameter is known as the Vredefort Dome. The structural uplift is ~20-30 km (Grieve et al., 2008).
Crater Morphology
Complex
Central Uplift Diameter
80 km
Central Uplift Height
Unknown
Uplift Reliability Index
3
Structural Uplift
30 km
Thickness of Seds
Unknown
Target Age
Precambrian
Marine
No
Impactor Type
Unknown
Other Shock Metamorphism
Shocked monazite Shock xenotime Shocked zircon
  1. Detrital shocked monazite (Cavosie et al. 2010; Erickson et al. 2013a; Erickson et al., 2016; Cavosie et al. 2018; Fougerouse et al., 2021) Shocked monazite in bedrock (Erickson et al., 2017) Detrital shocked xenotime (Cavosie et al., 2021) Detrital shocked zircon (Cavosie et al. 2010; Erickson et al. 2013a, b; Cavosie et al. 2015; Montalvo et al., 2017; Cavosie et al. 2018) Shocked zircon in bedrock (Moser et al. 2011; Erickson et al., 2017)"
Shatter Cones
Yes
  1. Incomplete shatter cone segments are very common, but complete cones extremely rare (Hargraves, 1961) (Manton, 1965) (Albat, 1988). Shatter cones or evidence of of them were found all around the perimeter of the Vredefort ring (Fig. 1), occuring in most of all quartzite units, in relatively fine-grained alkali granite, in an outcrop of basic schist inclusions in the Archean granite, hornfels, slate, epidiorite and in amygdaloid (Hargraves, 1961, page 2). The smallest (1/4 inch long) of shatter cones occurred in shale of the Government Reef Series (Fig. 2; Manton, 1965), and the largest (four feet long) were in thickly bedded Main-Bird quartzite (Manton, 1965). The average length was between 9 and 18 inches (Manton, 1965). (Nicolaysen and Reimold, 1999) studied shatter cone samples from three locations of Vredefort crater and concluded a later generation of shatter cones, rather than an early generation during the compression stage of shock. Fig 12 (Grieve et al., 2008) shows a map of the outer limits of shatter cones and PDFs in the Vredefort structure, scaled and overlain over a map the same features in the Sudbury impact structure. Shatter cones in quartzite units of the Witwatersrand Supergroup as well as the less exposed shales found in road-cuts in the northwestern part of the collar (Wieland et al., 2006). Rare cones found as far as 65 km north of the centre of the dome (Wieland et al., 2006). The abundance of shatter cones is enhanced in finer-grained rocks, however, the size of shatter cones does not seem to depend on the grain size of the host lithology: cones of both small (tens of cm diameter) and large (80-100 cm) were found in fine-grained shale, and medium and coarse-grained quartzite (Wieland et al., 2006).
Planar Fractures
Yes
  1. (Erickson et al., 2013) identified planar fractures (Fig. 5a) in detrital shocked zircon eroded from the Vredefort dome with orientations {1 1 2}, (0 1 0), (1 0 0) and (0 1 1). Planar fractures in shocked monazite from bedrocks (Erickson et al., 2013).
Planar Deformation Features
Yes
  1. PDF in quartz grains (Carter, 1965) (Grieve et al., 1990) (Leroux et al., 1994). Shocked zircons in breccia (Kamo et al., 1995). Decorated PDFs in shocked detrital quartz (Fig. 4; Erickson et al., 2013). Decorated planar features in quartz (with, 0001) orientation (Carter, 1965) (Leroux et al., 1994).
Diaplectic Glass
Yes
  1. Coesite and stishovite discovered in very thin pseudotachylite veins developed in Witwatersrand quartzites are associated with microcrystalline fibrous quartz which is interpreted as reverted diaplectic silica glass (Martini, 1978).
Coesite
Yes
  1. (Martini, 1978) (Martini, 1991) (Halvorson and McHone, 1992). Coesite occurs in shock veins as square, poorly shaped crystals typically 2 x 2 microns in size, but can be larger (2 x 4) and more rectangular (Spray and Boonsue, 2009). Small (~1µ) grains of coesite present, showing no preferred orientation and appear to be restricted to the immediate vicinity of pseudotachylite veinlets (Carter, 1965). Coesite and stishovite discovered in very thin pseudotachylite veins developed in Witwatersrand quartzites of the collar of the Vredefort Dome (Martini, 1978). Coesite forms angular crystals and rosettes of needles reaching a maximum length of 100 µm (Fig. 1; Martini, 1978).
Stisovite
Yes
  1. (Martini, 1978) (Martini, 1991) (Halvorson and McHone, 1992). Stishovite occurs within, and at the boundaries of SiO2 clasts, forming acicular needles up to 10 microns long and 0.5 micron wide that radiate from clast margins and vein walls (Spray and Boonsue, 2009). Coesite and stishovite discovered in very thin pseudotachylite veins developed in Witwatersrand quartzites of the collar of the Vredefort Dome (Martini, 1978). Stishovite occurs in a similar manner as the coesite discovered but with shorter needles (<10 µm).
Crater Fill
MB
  1. Spherules composed of silicate occur on shatter cone surfaces from the collar of the crater; they are most spherical on shatter cones from shale horizon; diameter of spherules range from 0.1 to 10 microns; (Gay, 1976). Dyke contains granular and spherulitic melt breccia (Fig. 3d; Kamo et al., 1996), pseudotachylite breccia with recrystallized clasts in a fine-grain matrix; the breccia clasts are up to several cm wide in a fine grain, crystalline, mosaic-textured matrix of euhedral to anhedral quartz, feldspar, biotite and pyroxene (Fig. 2(a), Kamo et al., 1996) narrow (<5cm) pseudotachylite veinlets are present. Veins have glassy or microcrystalline matrix and contains a few large annealed grains (Leroux et al., 1994). Pseudotachylitic veins are abundant in the central uplift. Dykes of fine-grained melt rock (Vredefort Granophyre) occur in the parautochthonous rocks of the crater floor (Reimold and Gibson, 2006) (Grieve and Therriault, 2012).
Proximal Ejecta
Unknown
Distal Ejecta
Unknown
Dykes
LB, M, P
Volume of Melt
Unknown
Depth of Melting
Unknown

References

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R S Dietz (1961) Vredefort ring structure; meteorite impact scar?, Journal of Geology 69(5), p. 499-516, University of Chicago Press, Chicago, IL, url

S Carey (1962) Scale of geotectonic phenomena, Journal of the Geological Society of India 3, p. 97-105, Geological Society of India, Bangalore, url

N L Carter (1965) Basal quartz deformation lamellae; a criterion for recognition of impactites, American Journal of Science 263(9), p. 786-806, Kline Geology Laboratory, Yale University, New Haven, CT, url

W H Bucher (1965) The largest so-called meteorite scars in three continents as demonstrably tied to major terrestrial structures, Annals of the New York Academy of Sciences 123, p. 897-903, New York Academy of Sciences, New York, NY, url

R B Hargraves (1970) Paleomagnetic evidence relevant to the origin of the Vredefort ring, Journal of Geology 78(3), p. 253-263, University of Chicago Press, Chicago, IL, url

R C Rhodes (1975) New evidence for impact origin of the Bushveld Complex, South Africa, Geology (Boulder) 3(10), p. 549-554, Geological Society of America (GSA), Boulder, CO, url

N C Gay (1976) Spherules on shatter cone surfaces from the Vredefort Structure, southern, Africa, Science 194(4266), p. 724-725, American Association for the Advancement of Science, Washington, DC

J E J Martini (1978) Coesite and stishovite in the Vredefort Dome, South Africa, Nature (London) 272(5655), p. 715-717, Macmillan Journals, London, url

N C Gay, N R Comins, C Simpson (1978) The composition of spherules and other features on shatter cones surfaces from the Vredefort Structure, South Africa, Earth and Planetary Science Letters 41(3), p. 372-380, Elsevier, Amsterdam, url

P A Lilly, J E J Martini (1979) Coesite and stishovite in the Vredefort, South Africa; discussion and reply, Nature (London) 277(5696), p. 495-496, Macmillan Journals, London

R A F Grieve (1982) The Vredefort Structure still not understood, Nature (London) 295(5851), p. 644-645, Macmillan Journals, London, url

B M French (1983) Bushveld igneous complex, South Africa: absence of shock-metamorphic effects after an extensive search, Lunar and Planetary Science XIV, p. 211-212, url

L O Nicolaysen, W U Reimold (1985) Shock deformation, shatter cones, and pseudotachylite at Vredefort: a review of major unsolved problems and current efforts to resolve them, Lunar and Planetary Science XVI, p. 618-619, url

S C Solomon, E D Duxbury (1987) A test of the longevity of impact-induced faults as preferred sites for later tectonic activity, Journal of Geophysical Research 92(B4), Graham Ryder, Gerald Schubert (ed.), p. E759-E768, American Geophysical Union, Washington, DC, doi:http://dx.doi.org/10.1029/JB092iB04p0E759

W U Reimold (1988) Report on an international workshop on Cryptoexplosions and Catastrophes in the Geological Record, with a Special Focus on the Vredefort Structure, LPI Contributions (673), p. 150-151, In Lunar and Planetary Inst., Global Catastrophes in Earth History: An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality p 150-151 (SEE N89-21287 14-42), url

W U Reimold, M A G Andreoli, R J Hart (1988) Microdeformation in Vredefort rocks; evidence for shock metamorphism, LPI Contributions 673(152-153), url

R A F Grieve, C A Wood, J B Garvin, G McLaughlin, J F McHone (1988) Impact Craters in Africa, Astronaut's Guide to Terrestrial Impact Craters, Richard A. F. Grieve, Charles A Wood, J. B. Garvin, G McLaughlin, J F McHone (ed.), p. 58, url

H M Albat, J J Mayer (1989) Megascopic planar shock fractures in the Vredefort Structure; a potential time marker?, Tectonophysics 162(3-4), p. 265-276, Elsevier, Amsterdam, url

B O Dressler (1990) Shock metamorphic features and their zoning and orientation in the Precambrian rocks of the Manicouagan Structure, Quebec, Canada, Tectonophysics 171(1-4), L O Nicolaysen, W U Reimold (ed.), p. 229-245, Elsevier, Amsterdam, url, doi:10.1016/0040-1951(90)90101-D

W von Engelhardt (1990) Distribution, petrography and shock metamorphism of the ejecta of the Ries Crater in Germany; a review, Tectonophysics 171(1-4), L O Nicolaysen, W U Reimold (ed.), p. 259-273, Elsevier, Amsterdam, url

B M French, R L Nielsen (1990) Vredefort bronzite granophyre; chemical evidence for origin as a meteorite impact melt, Tectonophysics 171(1-4), L O Nicolaysen, W U Reimold (ed.), p. 119-138, Elsevier, Amsterdam, url

L O Nicolaysen (1990) The Vredefort structure: an introduction and a guide to recent literature, Tectonophysics 171(1-4), L O Nicolaysen, W U Reimold (ed.), p. 1-6, Elsevier, Amsterdam, url

R A F Grieve, J M Coderre, P B Robertson, J S Alexopoulos (1990) Microscopic planar deformation features in quartz of the Vredefort Structure; anomalous but still suggestive of an impact origin, Tectonophysics 171(1-4), L O Nicolaysen, W U Reimold (ed.), p. 185-200, Elsevier, Amsterdam, url

O Goltrant, P Cordier, J C Doukhan (1991) Planar deformation features in shocked quartz; a transmission electron microscopy investigation, Earth and Planetary Science Letters 106(1-4), p. 103-115, Elsevier, Amsterdam, url, doi:http://dx.doi.org/10.1016/0012-821X(91)90066-Q

J E J Martini (1991) The nature, distribution and genesis of the coesite and stishovite associated with the pseudotachylite of the Vredefort Dome, South Africa, Earth and Planetary Science Letters 103(1-4), p. 285-300, Elsevier, Amsterdam, url, doi:http://dx.doi.org/10.1016/0012-821X(91)90167-G

R J Hart, M A G Andreoli, W U Reimold, M Tredoux (1991) Aspects of the dynamic and thermal metamorphic history of the Vredefort cryptoexplosion structure: implications for its origin, Tectonophysics 192(3-4), p. 313-331, url, doi:10.1016/0040-1951(91)90106-3

O Goltrant, H Leroux, J C Doukhan, P Cordier (1992) Formation mechanisms of planar deformation features in naturally shocked quartz, Physics of the Earth and Planetary Interiors 74(3-4), p. 219-240, Elsevier, Amsterdam, url

M Trieloff, J Kunz, E K Jessberger, W U Reimold, R H Boer, M C Jackson (1992) Ar-40 to Ar-39 dating of pseudotachylites from the Witwatersrand basin, South Africa, with implications for the formation of the Vredefort Dome, Large Meteorite Impacts and Planetary Evolution, p. 75-77, In Lunar and Planetary Inst., International Conference on Large Meteorite Impacts and Planetary Evolution p 75-77 (SEE N93-10112 01-46), url

W U Reimold (1992) The Vredefort Dome: Review of geology and deformation phenomena and status report on current knowledge and remaining problematics (five years after the cryptoexplosion workshop), International Conference on Large Meteorite Impacts and Planetary Evolution, p. 59-60, In Lunar and Planetary Inst., International Conference on Large Meteorite Impacts and Planetary Evolution p 59-60 (SEE N93-10112 01-46), url

J C White (1992) Electron petrography of silica polymorphs associated with pseudotachylite, Vredefort structure, South Africa, Large Meteorite Impacts and Planetary Evolution, p. 78-79, In Lunar and Planetary Inst., International Conference on Large Meteorite Impacts and Planetary Evolution p 78-79 (SEE N93-10112 01-46), url

L A G Antoine, W U Reimold, W P Colliston (1992) A quasi-Hertzian stress field from an internal source: A possible working model for the Vredefort structure, International Conference on Large Meteorite Impacts and Planetary Evolution, p. 3-4, In Lunar and Planetary Inst., International Conference on Large Meteorite Impacts and Planetary Evolution p 3-4 (SEE N93-10112 01-46), url

A M Therriault, A M Reid, W U Reimold (1993) Origin of the Vredefort structure, South Africa: Impact model, Lunar and Planetary Science XXIV, p. 1421-1422, In Lunar and Planetary Inst., Twenty-Fourth Lunar and Planetary Science Conference. Part 3: N-Z p 1421-1422 (SEE N94-20636 05-91), url

W U Reimold (1993) Further debate on the origin of the Sudbury structure; is it relevant to the Vredefort Dome and the Bushveld Complex?, South African Journal of Science 89(11-12), p. 546-552, South African Association for the Advancement of Science, Johannesburg, url

C Koeberl (1994) African meteorite impact craters: characteristics and geological importance, Journal of African Earth Sciences 18(4), p. 263-295, url, doi:10.1016/0899-5362(94)90068-X

J Rondot (1994) Recognition of eroded astroblemes, Earth-Science Reviews 35(4), p. 331-365, Elsevier, Amsterdam, url, doi:http://dx.doi.org/10.1016/0012-8252(94)90001-9

A M Therriault, R A F Grieve, W U Reimold (1995) How big is Vredefort?, Meteoritics & Planetary Science 30(5), Derek W G Sears (ed.), p. 586-587, Meteoritical Society, Fayetteville, AR, url

S L Kamo, W U Reimold, T E Krogh, W P Colliston (1996) A 2.023 Ga age for the Vredefort impact event and a first report of shock metamorphosed zircons in pseudotachylitic breccias and granophyre, Earth and Planetary Science Letters 144(3-4), p. 369-387, Elsevier, Amsterdam, doi:http://dx.doi.org/10.1016/S0012-821X(96)00180-X

H Henkel, W U Reimold (1996) Integrated geophysical modelling of the Vredefort impact structure, Witwatersrand Basin, South Africa, Lunar and Planetary Science Conference (27), p. 527, url

W U Reimold, R L Gibson (1996) Geology and evolution of the Vredefort impact structure, South Africa, Journal of African Earth Sciences 23(2), p. 125-162, Elsevier, Oxford

E P Turtle, H J Melosh (1996) Finite-element modeling of the Vredefort impact structure with implications for the collapse and modification stage of large crater formation, Lunar and Planetary Science, v. XXVII, p. 1347, url

A M Therriault, R A F Grieve, W U Reimold (1997) Original size of the Vredefort structure; implications for the geological evolution of the Witwatersrand Basin, Meteoritics & Planetary Science 32(1), p. 71-77, Meteoritical Society, Fayetteville, AR, url

E P Turtle, E Pierazzo (1997) Constraints on the size of the Vredefort impact crater from numerical modeling, Lunar and Planetary Science XXVIII, p. 1459, 28th Annual Lunar and Planetary Science Conference, March 17-21, 1997, Houston, TX, p. 1459, url

C Koeberl, S B Shirey (1997) Re-Os isotope systematics as a diagnostic tool for the study of impact craters and distal ejecta, Palaeogeography, Palaeoclimatology, Palaeoecology 132(1-4), Helmut H J Geldsetzer, Michael M Joachimski (ed.), p. 25-46, Elsevier, Amsterdam

M C Brink, F B Waanders, A A Bisschoff (1997) Vredefort; a model for the anatomy of an astrobleme, Tectonophysics 270(1-2), p. 83-114, Elsevier, Amsterdam, url

R L Gibson, W U Reimold, T Wallmach (1997) Origin of pseudotachylite in the lower Witwatersrand Supergroup, Vredefort Dome (South Africa); constraints from metamorphic studies, Tectonophysics 283(1-4), p. 241-262, Elsevier, Amsterdam, url

D E Moser (1997) Dating the shock wave and thermal imprint of the giant Vredefort impact, South Africa, Geology (Boulder) 25(1), p. 7-10, Geological Society of America (GSA), Boulder, CO, url, doi:http://dx.doi.org/10.1130/0091-7613(1997)025<0007:DTSWAT>2.3.CO;2

R L Gibson, R A Armstrong, W U Reimold (1997) The age and thermal evolution of the Vredefort impact structure: A single-grain UPb zircon study, Geochimica et Cosmochimica Acta 61(7), p. 1531-1540, url, doi:10.1016/S0016-7037(97)00013-6

H E Frimmel (1997) Chlorite thermometry in the Witwatersrand Basin: Constraints on the Paleoproterozoic geotherm in the Kaapvaal Craton, South Africa, The Journal of Geology 105(5), url, doi:10.1086/515962

E P Turtle, E Pierazzo (1998) Constraints on the size of the Vredefort impact crater from numerical modeling, Meteoritics & Planetary Science 33(3), p. 483-490, Meteoritical Society, Fayetteville, AR, url

E P Turtle (1998) Finite-element modeling of large impact craters: implications for the size of the Vredefort structure and the formation of multiple ring craters, p. 4178, url

H Henkel, W U Reimold (1998) Integrated geophysical modelling of a giant, complex impact structure; anatomy of the Vredefort Structure, South Africa, Tectonophysics 287(1-4), p. 1-20, Elsevier, Amsterdam

R L Gibson, W U Reimold, G Stevens (1998) Thermal-metamorphic signature of an impact event in the Vredefort dome, South Africa, Geology 26(9), url, doi:10.1130/0091-7613(1998)026<0787:TMSOAI>2.3.CO;2

G Stevens, R A Armstrong, R L Gibson, W U Reimold (1999) Pre- and postimpact metamorphism in the core of the Vredefort Dome; clues to crustal response at a massive meteorite strike, Meteoritics & Planetary Science 34(4, Suppl.), p. 112, Meteoritical Society, Fayetteville, AR, url

L O Nicolaysen, W U Reimold (1999) Vredefort shatter cones revisited, Journal of Geophysical Research 104(B3), p. 4911, url, doi:10.1029/1998JB900068

J Rondot, W U Reimold (1999) About the size of the Vredefort impact crater, Meteoritics & Planetary Science 34(4, Suppl.), p. 98-99, Meteoritical Society, Fayetteville, AR

M C Brink, F B Waanders, A A Bisschoff, W U Reimold (1999) Evolution of the ringed basin around Vredefort, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 19-20, Meteoritical Society, Fayetteville, AR, pdf

C L Hayward, W U Reimold (1999) Fluid movement and gold remobilization triggered by the Vredefort impact, Witwatersrand Basin, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 52, Meteoritical Society, Fayetteville, AR, pdf

R L Gibson, W U Reimold (1999) The significance of the Vredefort Dome for the thermal and structural evolution of the Witwatersrand Basin, South Africa, Mineralogy and Petrology 66(1-3), H E Frimmel (ed.), p. 5-23, Springer-Verlag, Vienna, url

C S Bootsman, W U Reimold, W U Reimold (1999) Some comparative geomorphic aspects of the Morokweng and Vredefort impact structures, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 15, Meteoritical Society, Fayetteville, AR, url

H Henkel, W U Reimold (1999) Geophysical modeling of impact structures, Meteoritics & Planetary Science 34(4, Suppl.), p. 52-53, Meteoritical Society, Fayetteville, AR, url

S Ellis, W U Reimold, W U Reimold (1999) Post-transvaal supergroup age thrusting related to the collapse phase of the Vredefort impact event; examples from the western ring basin area, Meteoritics & Planetary Science 34(4, Suppl.), p. 34, Meteoritical Society, Fayetteville, AR, url

S N Foya, R L Gibson, W U Reimold, W U Reimold (1999) Impact-related hydrothermal alteration of Witwatersrand gold reefs in the Vredefort Dome and Witwatersrand goldfields, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 37-38, Meteoritical Society, Fayetteville, AR, pdf

W P Colliston, H E Praekelt, R van der Merwe, B Stevens, W U Reimold (1999) Recognition of Vredefort-related and pre-Vredefort deformation in the Vredefort impact structure, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 27-28, Meteoritical Society, Fayetteville, AR, url

R L Gibson, W U Reimold (1999) The metamorphic fingerprint of large impact events; the example of the Vredefort Dome, South Africa, Meteoritics & Planetary Science 34(4, Suppl.), p. 42-43, Meteoritical Society, Fayetteville, AR, url

M Tredoux, R J Hart, R W Carlson, S B Shirey (1999) Ultramafic rocks at the center of the Vredefort Structure; further evidence for the crust on edge model, Geology (Boulder) 27(10), p. 923-926, Geological Society of America (GSA), Boulder, CO, url, doi:http://dx.doi.org/10.1130/0091-7613(1999)027<0923:URATCO>2.3.CO;2

M E Phillips, M A Bussell, I McDonald, R J Hart, M A G Andreoli, W U Reimold (1999) A remote-sensing and geological investigation of the Vredefort impact structure (South Africa) using Landsat thematic mapper imagery, Meteoritics & Planetary Science 34(4, Suppl.), p. 92-93, Meteoritical Society, Fayetteville, AR, url

R Grieve, A Therriault (2000) Vredefort, Sudbury, Chicxulub; three of a kind?, Annual Review of Earth and Planetary Sciences 28, p. 305-338, Annual Reviews, Palo Alto, CA, url

M C Brink, F B Waanders, A A Bisschoff, N C Gay (2000) The Foch Thrust-Potchefstroom Fault structural system, Vredefort, South Africa; a model for impact-related tectonic movement over a pre-existing barrier, Journal of African Earth Sciences 30(1), p. 99-117, Pergamon, Oxford, url

R L Gibson, W U Reimold (2000) Deeply exhumed impact structures: A case study of the Vredefort structure, South Africa, Impacts and the Early Earth 91, Iain Gilmour, Christian Koeberl (ed.), p. 249-277, Berlin/Heidelberg: Springer-Verlag, url, doi:10.1007/BFb0027753

R J Hart, S H Connell, M Cloete, L Mare, M Drury, M Tredoux (2000) "Super magnetic" rocks generated by shock metamorphism from the centre of the Vredefort impact structure, South Africa, South African Journal of Geology 103(2), p. 151-155, Bureau for Scientific Publications, Pretoria, url, doi:http://dx.doi.org/10.2113/103.2.151

P S Buchanan, W U Reimold, G J Consolmagno (2001) Impact-related features in lithic clasts from the Vredefort Granophyre, South Africa, Meteoritics & Planetary Science 36(9, Suppl.), p. 31, Meteoritical Society, Fayetteville, AR, url

R L Gibson, W U Reimold, G J Consolmagno (2001) Petrographic evidence for high shock pressures and shock pressure heterogeneity in the Vredefort impact structure, South Africa, Meteoritics & Planetary Science 36(9, Suppl.), p. 65, Meteoritical Society, Fayetteville, AR, pdf

R L Gibson (2002) Impact-induced melting of Archean granulites in the Vredefort Dome, South Africa; I, Anatexis of metapelitic granulites, Journal of Metamorphic Geology 20(1), Geoffrey L Clarke, Michael Brown (ed.), p. 57-70, Blackwell, Oxford, url, doi:http://dx.doi.org/10.1046/j.0263-4929.2001.00358.x

C Koeberl, B Peucker-Ehrenbrink, W U Reimold, A Shukolyukov, G W Lugmair (2002) Comparison of the osmium and chromium isotopic methods for the detection of meteoritic components in impactites; examples from the Morokweng and Vredefort impact structures, South Africa, Special Paper - Geological Society of America 356, Christian Koeberl, Kenneth G MacLeod (ed.), p. 607-617, Geological Society of America (GSA), Boulder, CO, url

P C Buchanan, W U Reimold (2002) Planar deformation features and impact glass in inclusions from the Vredefort Granophyre, South Africa, Meteoritics & Planetary Science 37(6), p. 807-822, Meteoritical Society, Fayetteville, AR, url

W U Reimold, H Leroux, R L Gibson (2002) Shocked and thermally metamorphosed zircon from the Vredefort impact structure, South Africa; transmission electron microscopic study, European Journal of Mineralogy 14(5), p. 859-868, Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller), Stuttgart, url, doi:http://dx.doi.org/10.1127/0935-1221/2002/0014-0859

R Gersonde, A Deutsch, B A Ivanov, F T Kyte (2002) Oceanic impacts; a growing field of fundamental geoscience, Deep-Sea Research. Part II: Topical Studies in Oceanography 49(6), p. 951-957, Pergamon, Oxford, url, doi:http://dx.doi.org/10.1016/S0967-0645(01)00134-5

H Henkel, W U Reimold (2002) Magnetic model of the central uplift of the Vredefort impact structure, South Africa, Journal of Applied Geophysics 51(1), p. 43-62, Elsevier, Amsterdam

D A Kring (2003) Environmental consequences of impact cratering events as a function of ambient conditions on Earth, Astrobiology 3(1), Frank T Kyte (ed.), p. 133-152, Mary Ann Liebert, Larchmont, NY, url

E P Turtle, E Pierazzo, D P O'Brien (2003) Numerical modeling of impact heating and cooling of the Vredefort impact structure, Meteoritics & Planetary Science 38(2), p. 293-303, Meteoritical Society, Fayetteville, AR

L L Perchuk, L V Sazonova, D D Van Rinen, T V Gerya (2003) Ultramylonites and their significance for understanding the history of the Vredefort explosive structure, South Africa, Petrologiya 11(2), p. 128-144, MAIK Nauka/Interperiodika, Moscow, url

R M Flowers, D E Moser, R J Hart (2003) Evolution of the amphibolite-granulite facies transition exposed by the Vredefort impact structure, Kaapvaal Craton, South Africa, Journal of Geology 111(4), p. 455-470, University of Chicago Press, Chicago, IL, url

B O Dressler, W U Reimold (2004) Order or chaos? Origin and mode of emplacement of breccias in floors of large impact structures, Earth-Science Reviews 67(1-2), p. 1-54, Elsevier, Amsterdam, doi:http://dx.doi.org/10.1016/j.earscirev.2004.01.007

R A F Grieve, A M Therriault (2004) Observations at terrestrial impact structures; their utility in constraining crater formation, Meteoritics & Planetary Science 39(2), Elisabetta Pierazzo, Robert Herrick (ed.), p. 199-216, Meteoritical Society, Fayetteville, AR, url

B M French (2004) The importance of being cratered; the new role of meteorite impact as a normal geological process, Meteoritics & Planetary Science 39(2), Elisabetta Pierazzo, Robert Herrick (ed.), p. 169-197, Meteoritical Society, Fayetteville, AR, url

L L Perchuk (2005) Configuration of PT trends as a record of high-temperature polymetamorphism, Doklady Earth Sciences 401(2), p. 311-314, MAIK Nauka/Interperiodika, Moscow, url

A P Jones, K Wünnemann, G D Price (2005) Modeling impact volcanism as a possible origin for the Ontong Java Plateau, Special Paper - Geological Society of America 388, Gillian R Foulger, James H Natland, Dean C Presnall, Don L Anderson (ed.), p. 711-720, Geological Society of America (GSA), Boulder, CO, url, doi:http://dx.doi.org/10.1130/2005.2388(40

L Carporzen, S A Gilder, R Hart (2005) Two distinct Verwey transitions in the shocked rocks from the Vredefort meteorite impact crater, AGU Fall Meeting Abstracts, p. A42, American Geophysical Union, Fall Meeting 2005, abstract #GP13A-0042, url

E P Turtle, E Pierazzo, G S Collins, G R Osinski, H J Melosh, J V Morgan, W U Reimold (2005) Impact structures; what does crater diameter mean?, Special Paper - Geological Society of America 384, Thomas Kenkmann, Friedrich P Hoerz, Alex Deutsch (ed.), p. 1-24, Geological Society of America (GSA), Boulder, CO, pdf

R Hart, L Carporzen, S A Gilder (2005) Paleomagnetism of Vredefort: Plasma, Lightning, or ?, AGU Fall Meeting Abstracts, p. A95, American Geophysical Union, Fall Meeting 2005, abstract #GP33A-0095, url

H R Wenk, I Lonardelli, S C Vogel, J Tullis (2005) Dauphiné twinning as evidence for an impact origin of preferred orientation in quartzite: An example from Vredefort, South Africa, Geology 33(4), p. 273, url, doi:10.1130/G21163.1

D J Dunlop (2005) Magnetic impact craters, Nature (London) 435(7039), p. 156-157, Macmillan Journals, London, url

F B Waanders, L R Tiedt, M C Brink, A A Bisschoff (2005)

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