Hostname: page-component-5d84bcc8dc-hjvrn Total loading time: 0 Render date: 2026-09-04T20:17:55.944Z Has data issue: false hasContentIssue false
  • English
  • Français

Clay mineralogy in southern Africa river muds

Published online by Cambridge University Press:  27 February 2018

M. Setti ,
A. Lόpez-Galindo ,
M. Padoan  and
E. Garzanti
M. Setti*
Affiliation:
Dipartimento di Scienze della Terra e dell‘Ambiente, Università di Pavia, Via Ferrata 1, 27100 Pavia, Italy
A. Lόpez-Galindo
Affiliation:
Instituto Andaluz de Ciencias de la Tierra. CSIC-UGR. Avenide de las Palmera 4, 18100 Armilla, Granada, Spain
M. Padoan
Affiliation:
Laboratory for Provenance Studies, Department of Earth and Environmental Sciences, Università di Milano-Bicocca, Piazza della Scienza 4, 20216 Milano, Italy
E. Garzanti
Affiliation:
Laboratory for Provenance Studies, Department of Earth and Environmental Sciences, Università di Milano-Bicocca, Piazza della Scienza 4, 20216 Milano, Italy
*
*E-mail: massimo.setti@unipv.it
Get access Rights & Permissions [Opens in a new window]

Abstract

The composition, morphology and crystal order of clay minerals in silt-sized sediments carried in suspensions from 25 major rivers across tropical southern Africa have been studied by X-ray diffractometry and scanning and transmission electron microscopy. Our goal was to determine the spatial variability of clay-mineral associations in diverse geological settings, and in climatic conditions ranging from humid Angola and Zambia to hyperarid Namibia and the Kalahari. Specific attention was paid to the micromorphology and chemical composition of smectite particles. The relative abundance of smectites, illite/mica, kaolinite and chlorite enabled identification of regions characterized by different physical and chemical processes: (1) negligible chemical weathering is documented in Namibia, where river muds mostly contain illite/mica or smectite derived from Damara metasedimentary or Etendeka volcanic rocks; (2) kaolinite documenting intense weathering, reaches a maximum in the Okavango, Kwando and Upper Zambezi, sourced in subequatorial Angola and Zambia; (3) suspended-load muds in the Limpopo and middle Zambezi catchments display intermediate features, with varied assemblages and smectite compositions reflecting diverse parent lithologies. Clay mineralogy and chemical composition are confirmed as a most effective tool to unravel present and past climatic conditions on a continental scale.

Keywords

clay mineralschemical weatheringZambezi RiverLimpopo RiverOkavango riversSouth Africa

Information

Type
Research Article
Information
Clay Minerals , Volume 49 , Issue 5 , December 2014 , pp. 717 - 733
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2014

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Al-Juboury, I. (2009) Palygorskite in Miocene rocks of northern Iraq: environmental and geochemical indicators. Acta Geologica Polonica, 59, 269–282.Google Scholar
April, R.H. (1981) Trioctahedral smectite and interstratified chlorite/smectite in Jurassic strata of the Connecticut Valley. Clays and Clay Minerals, 29, 31–39.Google Scholar
Biscaye, P.E. (1965) Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent seas and oceans. Geological Society of America Bulletin, 76, 803–831.CrossRefGoogle Scholar
Bradley, W.H. & Fahey, J.J. (1962) Occurrence of stevensite in the Green River Formation of Wyoming. American Mineralogist, 47, 996–998.Google Scholar
Bremner, J.M. & Willis, J.P. (1993) Mineralogy and geochemistry of the clay fraction of sediments from the Namibian continental margin and the adjacent hinterland. Marine Geology, 115, 85–116.Google Scholar
Campbell, I.B. & Claridge, G.G.C. (1987) Antarctica: Soils, Weathering Processes and Environment. Developments in Soil Sciences. Elsevier, Amsterdam.Google Scholar
Chamley, H. (1989) Clay Sedimentology. Springer, Berlin.Google Scholar
Duzgoren-Aydin, N.S., Aydin, A. & Malpas, J. (2002) Reassessment of chemical weathering indices: case study on pyroclastic rocks of Hong Kong. Engineering Geology, 63, 99–119.Google Scholar
Dyni, J.R. (1976) Trioctahedral smectite in the Green River Formation, Duchesne County, Utah. Geological Survey Professional Paper 967, United States Geological Survey.Google Scholar
Eitel, B., BlÜmel, W.D. & Mauz, B. (2001) Dust and loessic alluvial deposits in northwestern Namibia (Damaraland, Kaokoveld): sedimentology and palaeoclimatic evidence based on luminescence data. Quaternary International, 76/77, 57–65.Google Scholar
Eitel, B., Kadereit, A., BlÜmel, W.D., HÜser, K., Lomax, J. & Hilgers, A. (2006) Environmental changes at the eastern Namib Desert margin before and after the Last Glacial Maximum: new evidence from fluvial deposits in the upper Hoanib River catchment, northwestern Namibia. Palaeogeography, Palaeoclimatology, Palaeoecology, 234, 201–222.Google Scholar
Emeis, K.C. (1985) Particulate suspended matter in major world rivers, Part II: Results on the rivers Indus, Waikato, Nile, St. Lawrence, Yangtse, Parana, Orinoco, Caroni, and Mackenzie. Pp. 593–617 in: Transport of Carbon and Minerals in Major World Rivers, Part I (E.T. Degens, S. Kempe & R. Herrera, R., editors). Mitt. Geol.-Paläont. Institut Univ. Hamburg, Hamburg.Google Scholar
Emeis, K.C. & Stoffers, P. (1982) Particulate suspended matter in major world rivers: EDX analysis, scanning electron microscopy, and X-ray diffraction study of filters. Pp. 529–554 in: Transport of Carbon and Minerals in Major World Rivers (E.T. Degens, editor). Mitt. Geol.- Paläont. Institut Univ. Hamburg, Hamburg.Google Scholar
Ewart, A., Marsh, J.S., Milner, S.C., Duncan, A.R., Kamber, B.S. & Armstrong, R.A. (2004) Petrology and geochemistry of Early Cretaceous bimodal continental flood volcanism of the N. Etendeka, Namibia. Journal of Petrology, 45, 59–138.Google Scholar
Gaillardet, J., Dupré, B. & Alle`gre, C.J. (1999) Geochemistry of large river suspended sediments: silicate weathering or recycling tracer? Geochimica et Cosmochimica Acta, 63, 4037–4051.CrossRefGoogle Scholar
Galán, E. (2006) Genesis of Clay Minerals. Pp. 1129–1162 in: Handbook of Clay Science (F. Bergaya, B.K.G. Theng & G. Lagaly, editors). Elsevier: Amsterdam, 1129-1162.Google Scholar
Galán, E. & Pozo, M. (2011). Palygorskite and sepiolite deposits in continental environments. Description, genetic patterns and sedimentary settings. Pp. 125–173 in: Developments in Clay Science (E. Gala`n & A. Singer, editors). Elsevier, Amsterdam.Google Scholar
Garzanti, E., Padoan, M., Setti, M., Najman, Y., Peruta, L. & Villa, I.M. (2013) Weathering geochemistry and Sr-Nd fingerprints of equatorial upper Nile and Congo muds. Geochemistry, Geophysics, Geosystems, 14, 292–316.Google Scholar
Garzanti, E., Padoan, M., Setti, M., Lόpez-Galindo, A. & Villa, I.M. (2014a) Provenance versus weathering control on the composition of tropical river mud (southern Africa). Chemical Geology, 366, 61–74.Google Scholar
Garzanti, E., Vermeesch, P., Padoan, M., Resentini, A., Vezzoli, G. & Ando`, S. (2014b) Provenance of passive-margin sand (southern Africa). The Journal of Geology, 122, 17–42.CrossRefGoogle Scholar
Grauby, O., Petit, S., Decarreau, A. & Baronnet, A. (1993) The beidellite-saponite series: an experimental approach. European Journal of Mineralogy, 5, 623–635.CrossRefGoogle Scholar
Gray, D.R., Foster, D.A., Meert, J.G., Goscombe, B.D., Armstrong, R., Trouw, R.A.J. & Passchier, C.W. (2008) A Damara Orogen perspective on the assembly of southwestern Gondwana. Pp. 257–278 in: West Gondwana: pre-Cenozoic Correlations across the South Atlantic Region (R.J. Pankhurst, R.A.J. Trouw, B.B. Brito Neves & M.J. De Wit, editors). Geological Society, London.Google Scholar
GÜven, N. (1988) Smectites. Pp. 497–559 in: Hydrous Phyllosilicates (Exclusive of Micas) (S.W. Bailey, editor). Reviews in Mineralogy, 19. Mineralogical Society of America.Google Scholar
Hanson, R.E. (2003) Proterozoic geochronology and tectonic evolution of southern Africa. Pp. 427–463 in: Proterozoic East Gondwana: Supercontinent Assembly and Breakup (M. Yoshida, B.F. Windley & S. Dasgupta editors). Geological Society, London.Google Scholar
Hardie, L., Smoot, J. & Eugster, H. (1978) Saline lakes and their deposits: a sedimentological approach. Pp. 7–41 in: Modern and Ancient Lake Sediments (A. Matter & M. Tucker, editors). Special Publications of the International Association of Sedimentologist. John Wiley & Sons, Ltd, Oxford.Google Scholar
Hay, W.W. (1998) Detrital sediment fluxes from continents to oceans. Chemical Geology, 145, 287–323.Google Scholar
Hillier, S. (1995) Erosion, sedimentation and sedimentary origin of clays. Pp. 162–219 in: Origin and Mineralogy of Clays (B. Velde, editor). Springer, Berlin.Google Scholar
Johnsson, M.J., Stallard, R.F. & Lundberg, N. (1991) Controls on the composition of fluvial sands from a tropical weathering environment: Sands of the Orinoco River drainage basin, Venezuela and Colombia. Geological Society of America Bulletin, 12, 1622–1647.Google Scholar
Jones, B.F. (1986) Clay mineral diagenesis in lacustrine sediments. Pp. 291–300 in: Studies in Diagenesis (F.A. Mumpton, editor). U.S. Geological Survey Bulletin, 1578.Google Scholar
Khormali, F., Abtahi, A. & Owliaie, H.R. (2005) Late Mesozoic-Cenozoic clay mineral successions of southern Iran and their palaeoclimatic implications. Clay Minerals, 40, 191–203.Google Scholar
Konta, J. (1985) Mineralogy and chemical maturity of suspended matter in major rivers sampled under the, S.O.E/UNEP Project. Pp. 569–592 in: Transport of Carbon and Minerals in Major World Rivers, Part 3 (E.T. Degens, S. Kempe & R. Herrera, editors). Mitt. Geol.-Paläont. Institut Univ. Hamburg, Hamburg.Google Scholar
Lisitzin, A.P. (1972) Sedimentation in the World Ocean. Society of Economic Paleontologists and Mineralogists. Special Publications.Google Scholar
Mayayo, M.J., Torres-Ruiz, J., Gonzalez-Lόpez, J.M., Lόpez-Galindo, A. & Bauluz, B. (1998) Mineralogical and chemical characterization of the sepiolite/Mgsmectite deposit at Mara (Calatayud basin, Spain). European Journal of Mineralogy, 10, 367–383.Google Scholar
McCarthy, T.S. & Ellery, W.N. (1995) Sedimentation on the distal reaches of the Okavango Fan, Botswana, and its nearing on calcrete and silcrete (Ganister) formation. Journal of Sedimentary Research, A65, 77–79.Google Scholar
Millot, G. (1970) Geology of Clays. Springer-Verlag, New York.Google Scholar
Moore, D.M. & Reynolds, R.C. (1989) X-ray diffraction and the Identification and Analysis of Clay Minerals. Oxford University Press, New York.Google Scholar
Nesbitt, H.W. & Young, G.M. (1982) Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature, 299, 715–717.Google Scholar
Papke, K.G. (1970) Montmorillonite, bentonite, and fuller’s earth deposits in Nevada. Nevada Bureau Mines Bulletin, Nevada-Reno.Google Scholar
Papke, K.G. (1972) A seprolite-rich playa deposit in southern Nevada. Clays and Clay Minerals, 20, 211–215.CrossRefGoogle Scholar
Paquet, H., Duplay, J., Valleron-Blanc, M.M. & Millot, G. (1987) Octahedral composition of individual particles in smectite-palygorskite and smectite-sepiolite assemblages. Pp. 73–77 in: Proceedings of the International Clay Conference, Denver, 1985 (L.G. Schultz, H. van Olphen & F.A. Mumpton, editors). The Clay Minerals Society, Bloomington, Indiana.Google Scholar
Parker, A. (1970) An index of weathering for silicate rocks. Geological Magazine 107, 501–504.Google Scholar
Pozo, M. & Casas, J. (1999) Origin of kerolite and associated M. clays in palustrine-lacustrine environments. The Esquivias deposit (Neogene Madrid Basin, Spain). Clay Minerals, 34, 395–418.Google Scholar
Setti, M., Marinoni, L., Lopez-Galindo, A. & Ben Aboud, A. (1997) XRD, SEM and T.M. investigation of smectites of the Core C.R. S-1 (Ross Sea, Antarctica). Terra Antartica, 4, 119–125.Google Scholar
Setti, M., Marinoni, L., Lόpez-Galindo, A. & Delgado- Huertas, A. (2000) Compositional and morphological features of smectites in sediments from C.P. 2/2A, Victoria Land Basin, Antarctica. Terra Antartica, 7, 581–587.Google Scholar
Setti, M., Marinoni, L. & Lόpez-Galindo, A. (2001) Crystal-chemistry of smectites in sediments of C.P. 3 drillcore (Victoria Land Basin, Antarctica): preliminary results. Terra Antartica, 8, 543–550.Google Scholar
Setti, M., Marinoni, L., Lόpez-Galindo, A. & Ben Aboud, A. (1998) TEM observations and Rare Earth Element Analysis on the clay minerals of the C.P. 1 Core (Ross Sea Antarctica). Terra Antartica, 5, 621–626.Google Scholar
Setti, M., Marinoni, L. & Lόpez-Galindo, A. (2004) Mineralogical and geochemical characteristics (major, minor, trace elements and R.E. of detrital and authigenic clay minerals in a Cenozoic sequence from Ross Sea, Antarctica. Clay Minerals, 39, 405–421.Google Scholar
Singer, A. (1984) The paleoclimatic interpretation of clay minerals in sediments: a review. Earth-Science Reviews, 21, 251–293.Google Scholar
Thiry, M. (2000) Palaeoclimatic interpretation of clay minerals in marine deposits: an outlook from the continental origin. Earth-Science Reviews, 49, 201–221.CrossRefGoogle Scholar
Thomas, D.S.G. & Shaw, P.A. (1990) The deposition and development of the Kalahari Group sediments, central southern Africa. Journal of African Earth Sciences, 10, 187–197.Google Scholar
Velde, B. (1995) Origin and Mineralogy of Clays. Springer Verlag, Berlin.Google Scholar
Verrecchia, E.P. & Le Coustumer, M.N. (1996) Occurrence and genesis of palygorskite and associated clay minerals in a Pleistocene calcrete complex, Sde Boqer, Negev Desert , Israel. Clay Minerals, 31, 183–202.Google Scholar
Viers, J., Dupré, B. & Gaillardet, J. (2009) Chemical composition of suspended sediments in world rivers: new insights from a new database. Science of the Total Environment, 407, 853–868.CrossRefGoogle ScholarPubMed
Weaver, C.E. (1989) Clays, Muds and Shales. Developments in Sedimentology, 44. Elsevier, Amsterdam.Google Scholar
Weaver, C.E. & Pollard, L.D. (1973) The Chemistry of Clay Minerals. Developments in Sedimentology, 15. Elsevier, Amsterdam.Google Scholar
Zabel, M., Schneider, R.R., Wagner, T., Adegbie, A.T., de Vries, U. & Kolonic, S. (2001) Late Quaternary climate changes in Central Africa as inferred from terrigenous input to the Niger Fan. Quaternary Research, 56, 207–217.Google Scholar