| | Report (chapter) | on July 30, 2015 Chapter 15 The Witvlei Group of East-Central Namibia A. R. PRAVE1*, K.-H. HOFFMANN2,... UK 2 Geological Survey of Namibia, 1 Aviation Road, Windhoek, Namibia 3 Scottish Universities Environmental...Abstract: The Witvlei Group is preserved in two regional synclinoria in the Gobabis-Witvlei area of east-central...east-central Namibia and as isolated outcrops 90 km SW of Rehoboth, itself some 200 km south of that area...Group. No direct age constrains exist for the Witvlei Group, but it post-dates c. 800 Ma rift-related | | | Journal (article/letter/editorial) | organic carbon from upper Proterozoic successions in Namibia: stratigraphic variation and the effects of diagenesis...organic carbon from upper Proterozoic successions in Namibia: stratigraphic variation and the effects of diagenesis...Proterozoic Damara Supergroup of Namibia, including the Nama, Witvlei, and Gariep groups on the Kalahari...immediately following three separate glacial episodes in Namibia. The correspondence between ice ages and negative...from the upper Proterozoic Damara Supergroup of Namibia. Insofar as carbon isotope signatures have proven | | | Journal (article/letter/editorial) | Samples from three Late Proterozoic basins in Namibia, Svalbard and East Greenland, and Australia were...ages in CONWAYMORRIS, 1989). Nama and Witvlei Groups, Namibia The Vendian to Early Cambrian Nama and...marine transgression over the Kalahari Craton in Namibia (KAUFMANet al., 199I ). Carbonates of the Nama...of laminated or massive calcite microspar with minor amount of sparry calcite. In contrast, Witviei Group...ss17 SHS4 SH49 KM092 KO137 KOMO KM05 KM3 KM111 D. Witvlei 203 393 159 188 X:Z 0.055 0.847 0.053 0.127 iii | | | Journal (article/letter/editorial) | equivalents in East Greenland, the Witvlei and Nama groups in Namibia and South Africa, and the upper Windermere...interpreted as lacustrine [10]. 2.2 Nama and Witvlei Groups, Namibia and South Africa The stratigraphy, sedimentology...paleontology and age of the Vendian Nama and Witvlei groups in Namibia have been the focus of several recent...information can be found there. In brief, the Witvlei Group and Kuibis and Schwarzrand subgroups of the...of the Witvlei Group [15]. Germs [13] indicated that an unconformity also separates the Witvlei and Nama | | | Journal (issue) | OcronER2011 The Kalahari Copperbelt in Central Namibia: Controls on Copper Mineralization Kenneth J. Ma/dent...central Namibia lo northern Botswana (Figure I; Borg, 1988; Borg and Moiden, 1989). In centml Namibia, copper...controlled sites lotc in the deformation histmy of the region. The conclusion of the prcscnl review is that economically...~tretches discontinuously for 800 km from central Namibia to northern Botswana (Borg and Maiden, 1989). Copper...sector of the belt, particularly arow1d Klein Aub, Witvlei, and Dorclabis, for many years (see, for example | | KAMPUNZU, A. B., AKANYANG, P., MAPEO, R. B. M., MODIE, B. N., WENDORFF, M. (1998) Geochemistry and tectonic significance of the Mesoproterozoic
Kgwebe metavolcanic rocks in northwest Botswana: implications
for the evolution of the Kibaran Namaqua-Natal Belt. Geological Magazine, 135 (5) 669-683 doi:10.1017/s001675689800123x | Journal (article/letter/editorial) | the Neoproterozoic (Pan-African) Damara belt in Namibia and Ghanzi-Chobe belt in Botswana (Fig. 1). The...southern and central Africa includes the Damaran (Namibia), Ghanzi-Chobe (Botswana), Lufilian Arc (Democratic...Mamuno in the southwest. In Namibia, its correlatives occur in the Witvlei and Klein Aub districts (Fig...Mesoproterozoic metavolcanic rocks in Botswana, Namibia and South Africa, and the distribution of main...sediments can be inferred from studies in the Witvlei area in Namibia. The Damara siliciclastic sequence is the | | | Journal (article/letter/editorial) | carbonate phases, such as aragonite or magnesian calcite, may experience alteration of the original bl3C...bl3C signature during stabilization as low-Mg calcite. Some of the myriad post-deposi tional processes...enriched during the formation of late-stage ferroan calcite cements (Al-Aasm & Veizer 1986; see also Gao &...Brasier et aI1990), Iran (Brasier et aI1990), Namibia (Kaufman et a1 1991, Derby et al 1992), South Australia...Anti-Atlas Mtns., Morocco; D Himalayas, India; G = Namibia; E = Meishucun, China; H = = B = Greenland/Spitsbergen; | | | Journal (article/letter/editorial) | Florida] at 17:04 31 May 2016 867 The Rocky Cape region of northwest Tasmania consists of thick, essentially...pore space occluded by coarse clear dolomite or calcite spar. These cement-rich rocks were generally not...ooids 0.5-1 mm in diameter in an abundant sparry calcite cement. Ooids are uncompacted suggesting early...habit. Minor late, pore-filling coarse-grained calcite spar is present in some samples. About half the...preservation and low Sr content suggest an original calcite mineralogy, in contrast to the limestone from the | | | Journal (article/letter/editorial) | centralAfricancopper thenortheastern extension Aub, Namibia,wherean orebodyof 7 Mt at a gradeof 2 beltinZa...subeconomiccratonicbranch,whichis up to 400 km widein Namibia, copperoccurrence with 1.5 to 2 percentCu is locatedat...a width of 180 to 240 km into Botswana,as Witvlei, Namibia (Anhaeusserand Button, 1973; Ruxtonand canbe...southwestern part of the sures of basementrocks in Namibia, but in northwestern Ghanzi-Chobe beltby Lithedand(1982)...Botswana, theonlyrecordisfromtheOkwaValleyat a dis- Namibia(Hegenberger andSeeger, 1980;Killick,1983).This | | | Book | REPUBLIC OF NAMIBIA - MINISTRY OF MINES AND ENERGY GEOLOGICAL SURVEY THE MINERAL RESOURCES OF NAMIBIA FIRST...ENERGY Of the several hundred minerals present in Namibia, around sixty have been exploited. some, such as...base metals and industrial minerals have helped Namibia rank amongst the top five mining countries in Africa...terms of production and reserves. In this context, Namibia is a major producer of copper, lead, zinc, cadmium...unpublished. It is evident that mineral exploration in Namibia, as elsewhere. has changed from serendipitous discoveries | | | Report (chapter) | and FeâMn deposits (e.g. SW Brazil, NW Canada, Namibia). Glacial associated chemical sediments provide...(Numees Formation, Port Nolloth Group), Gariep Belt, Namibia and South Africa. Haematite- and magnetite âjaspilite...NEOPROTEROZOIC GLACIATION correlative Ghaub diamictite in Namibia has an indistinguishable 238 U â 206Pb (IDTIMS)...the Otavi platform (Congo palaeocontinent) of Namibia, for example, the Keilberg cap dolostone is 6â...palaeobathymetric zones of the Otavi platform, northern Namibia (Hoffman et al. 2007). The datum for platform columns | | Milani, Lorenzo, Kinnaird, Judith A., Lehmann, JĂ©rĂ©mie, Naydenov, Kalin V., Saalmann, Kerstin, Frei, Dirk, Gerdes, Axel (2015) Role of crustal contribution in the early stage of the Damara Orogen, Namibia: New constraints from combined UâPb and LuâHf isotopes from the Goas Magmatic Complex. Gondwana Research, 28 (3) 961-986 doi:10.1016/j.gr.2014.08.007 | Journal (article/letter/editorial) | contribution in the early stage of the Damara Orogen, Namibia: New constraints from combined UâPb and LuâHf isotopes...sources. The Goas Magmatic Complex in Central Namibia consists of a suite of variably metamorphosed gabbros...Windhoek geological maps, Geological Survey of Namibia). 964 L. Milani et al. / Gondwana Research 28...detrital zircon dataset of 462 ages from Central Namibia. The summary plot is reproduced in a probability...Gondwana Research 28 (2015) 961â986 northern Namibia (Lobo-Guerrero Sanz, 2005), at Navachab Mine, in | | | Report (issue) | Alteration Green, white, or gray rocks rich in Fe-calcite and chlorite result from reaction of reducing fluids...drainage caused by oxidizing pyrite must be avoided. Calcite is present in 20 deposits in the database and may...may be present in many more. The presence of calcite mitigates against the development of acid mine drainage...enables solution of carbonates and replacement of calcite cement by native copper. Sulfide in the form of...UZBN VNZL YUGO ZIMB ZIRE ZMBA 11 COUNTRY Mexico Namibia Nigeria Norway Peru Pakistan Poland Philippines | | | Report (volume) | Otavi carbonate platform and foreslope, northern Namibia: evidence for large base-level and glacioeustatic...HEGENBERGER, W. & FALLICK, A. E. The Witvlei Group of East-Central Namibia 211 FRIMMEL, H. E. The Chameis...Chameis Gate Member, Chameis Group, Marmora Terrane, Namibia 217 FRIMMEL, H. E. The Kaigas and Numees formations...formations, Port Nolloth Group, in South Africa and Namibia 223 FRIMMEL, H. E. The Karoetjes Kop and Bloupoort... Neoproterozoic glacial records in the Yangtze Region, China 357 ZHU, M. & WANG, H. Neoproterozoic | | | Journal (article/letter/editorial) | 374 J. E. LEE AND D. A. GLENISTER feldspar, calcite,and accessory minerals: titanire, virtuallyno Cu...shallowOther constituentsof the matrix are sulfides,calcite, water conditions. The iron-copper sulfides and...have been recordedin the per mineralization of Witvlei, South West Africa, Hanging wall reef, where galenais...mineragraphic study of the copper-bearingformations in the Witvlei area, South West Africa: Geol. Soc. stratigraphically | | | Book | (mantovani@usp.br) R.McG. Miller PO Box 11222, Windhoek, Namibia (rmmiller@mweb.com.na) A. Misi Centro de Pesquisa...2004 in SaÌo Paulo (Brazil), 2005 in Windhoek (Namibia), 2006 in Punta del Este (Uruguay), 2007 in Stellenbosch...and Numees (Frimmel et al., 2002) formations of Namibia and the Jacadigo Group and Puga Formation of the...thermally subsiding basins, such as in northern Namibia, South Australia and northwestern Canada. The so-called...problematic fossil Otavia in middle Cryogenian rocks in Namibia as a sponge (Brain et al., 2001, 2003, 2008) and | | | Journal (article/letter/editorial) | a regionalscaleinclude,in spatialorder, pyrite-calcite,chalcopyriteankerite,andthe lavender(hematitic)zone...developed betweenthechalcopyrite-ankerite andpyrite-calcite regionalzones.Mineralzones at the depositare, from...northwestto southeast: pyrite-calcite,galena-calcite, chalcopyritecalcite,bornitc-calcite, chalcocite-chlorite...boundariesparallelto the sulfide-mineral zoneboundaries.Bornitc-calcite andchalcocite-chlorite zonesformore gradesin certain...similar,some pyrite-calcite-zone mineralswere probablyreplacedby galena-calcite-zone minerals,which | | | Journal (article/letter/editorial) | boundary in Oman, India, China, Australia, and Namibia, supporting the view that the oxygenation event...punctuated by grey limestones characterized by calcite pseudomorphs of small aragonite crystal fans that...Johnnie Formation with âŒ30% isopachous and sparry calcite cement; (C) pink to orange carbonate of the Rainstorm...ooids (not including the surrounding cement), calcite fans and micrite, considered the least altered...thicker sections found elsewhere in the Death Valley region (Corsetti and Kaufman, 2003). In contrast, the | | Sato, Hisatoshi, Tahata, Miyuki, Sawaki, Yusuke, Maruyama, Shigenori, Yoshida, Naohiro, Shu, Degan, Han, Jian, Li, Yong, Komiya, Tsuyoshi (2016) A high-resolution chemostratigraphy of post-Marinoan Cap Carbonate using drill core samples in the Three Gorges area, South China. Geoscience Frontiers, 7 (4) 663-671 doi:10.1016/j.gsf.2015.07.008 | Journal (article/letter/editorial) | (Narbonne et al., 1994; Kaufman et al., 1997), Namibia (summarized by Hoffman et al., 70 2007), Siberia...Hoffman et al., 2007; Tahata et al., 2013). In 85 Namibia, the different ÎŽ13C variations in the Cap Carbonate...the 152 Aijiahe-Wuhe area of the Three Gorges region (Fig. 1) and acquired drill core samples 153 ...of very fine acicular needles, 188 and equant calcite and dolospar. In fresher samples, large amounts...Upper Proterozoic Noonday dolomite, Death Valley Region, eastern California. Geological Society of America | | | Journal (article/letter/editorial) | sequence to the Marinoan glaciation in northern Namibia. ÎŽ34Ssulfate profiles and other geochemical characteristics...Maieberg Formation cap-carbonate sequence in northern Namibia is ideally suited for reconstructing the chemistry...heterogeneities. Previous work on capcarbonate sequences in Namibia and Death Valley has shown variations of 17â° to...northwest Canada and in the Maieberg Formation in Namibia, where they coalesce to form patch reefs. The âcrystal...fold-and-thrust belts in northwestern and north-central Namibia (Fig. 1). It is disconformably underlain by fluviatile | | Batumike, M.J., Cailteux, J.L.H., Kampunzu, A.B. (2007) Lithostratigraphy, basin development, base metal deposits, and regional correlations of the Neoproterozoic Nguba and Kundelungu rock successions, central African Copperbelt. Gondwana Research, 11 (3) 432-447 doi:10.1016/j.gr.2006.04.012 | Journal (article/letter/editorial) | increase southward in the Nguba basin. In the southern region, the Kyandamu Formation contains clasts from the...Ubendian belt (2.1â1.8 Ga) is observed in the âDomes regionâ (Unrug, 1988) and within the Katangan belt (Cahen...western part of the Lufilian Arc (Kolwezi-Tilwezembe region, Fig. 1) as an unsorted grey or greenish grey conglomerate...and may be faceted or striated. In the western region, this formation contains a continuous horizon that... from bottom to top (François, 1973a). In that region, total thickness increases from 25 m in Kakanda | | Ălvaro, J. Javier, Macouin, MĂ©lina, Bauluz, Blanca, Clausen, SĂ©bastien, Ader, Magali (2007) The Ediacaran sedimentary architecture and carbonate productivity in the Atar cliffs, Adrar, Mauritania: Palaeoenvironments, chemostratigraphy and diagenesis. Precambrian Research, 153 (3) 236-261 doi:10.1016/j.precamres.2006.11.010 | Journal (article/letter/editorial) | Taoudeni Basin, situated to the SW of the JbeÌliat region (the standard area where numerous lithostratigraphic...subdivisions recently used in the mapping of the region (Waters and Schofield, 2004; LahondeÌre et al....numerous hills, plateaux and jbels of the Adrar region. The uppermost part of the group in the Adrar area...glaciation, correlatable with the Ghaub glaciation of Namibia (Hoffman et al., 2004), the Nantuo glaciation of...wide, consists of slightly calcareous (dolomite/calcite microsparite to sparite cement ratio ranging from | | | Journal (article/letter/editorial) | acid for 10 min in an attempt to liberate Cr from calcite only (see Supplementary information). After centrifugation...correlated with similar features in China, Brazil and Namibia (see text for details). The negative (N1) ÎŽ13C...with calcite as chromate (CrO42â) species and that the concentration of Cr incorporated in calcite increases...Gaucher et al., 2003)), in the Nama and Witvlei Groups (Namibia; (Fölling and Frimmel, 2002; Grotzinger...transition between the Port Noloth and Nama Groups in Namibia. Future studies will have to include Cr isotope | | | Report (chapter) | southern margin of the Congo Craton, northern Namibia: facies, palaeogeography and hydrocarbon perspective...Ghaub Formation diamictite interval in northern Namibia and the major environmental change in the aftermath...peri-Gondwanan areas apart from the formerly glaciated region of northern Africa. In the Palaeozoic post-glacial...the late Cryogenian Ghaub glaciation of northern Namibia, a classical field location for research on this...Kennedy (2007). Geological overview In northern Namibia continental rifting occurred in the Late Neoproterozoic | | | Report (chapter) | for which microscopically well-preserved low-Mg calcite tests (e.g. foraminifera, brachiopods and belemnites)...obtained by targeted microsampling of fine-grained calcite (micrite), which is free of later recrystallization...strontium-isotope record is typically reconstructed from calcite that has relatively high strontium and low rubidium...a 760 + 1 Ma tuff in the Ombombo Subgroup, NW Namibia (Halverson et al. 2005); (3) a 716.5 + 0.2 Ma tuff...an ash bed in the Ghaub Formation in northern Namibia dated at 635 + 0.6 Ma (Hofmann et al. 2005) and |
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