Hostname: page-component-8448b6f56d-mp689 Total loading time: 0 Render date: 2024-04-25T04:21:11.569Z Has data issue: false hasContentIssue false
  • English
  • Français

Depositional environment and OSL chronology of the Homeb silt deposits, Kuiseb River, Namibia

Published online by Cambridge University Press:  20 January 2017

Pradeep Srivastava ,
George A. Brook ,
Eugene Marais ,
P. Morthekai  and
Ashok K. Singhvi
Pradeep Srivastava*
Affiliation:
Department of Geography, University of Georgia, Athens, GA 30602, USA
George A. Brook
Affiliation:
Department of Geography, University of Georgia, Athens, GA 30602, USA
Eugene Marais
Affiliation:
National Museum of Namibia, P.O. Box 1203, Windhoek, Namibia
P. Morthekai
Affiliation:
Physical Research Laboratory, Navrangpura, Ahmedabad 380009, India
Ashok K. Singhvi
Affiliation:
Physical Research Laboratory, Navrangpura, Ahmedabad 380009, India
*
*Corresponding author. Wadia institute of Himalayan Geology, 33 GMS Road, Dehradun-248001, India. E-mail address:pradeep@wihg.res.in (P. Srivastava).
Get access Rights & Permissions [Opens in a new window]

Abstract

Previous studies suggest that the Homeb silts of the Kuiseb valley, Namibia (i) accumulated in a dune-dammed lake, (ii) are end-point deposits, (iii) represent an aggrading river bed, and (iv) are slackwater deposits. Thus, they have been used alternatively as evidence of past drier conditions or past wetter conditions. Lithostratigraphic analysis of two sediment sequences at Homeb indicates sedimentation by aggradation of the Kuiseb River triggered by a transition from an arid to humid climate. OSL ages for the sequences were obtained by the SAR protocol on aliquots of 9.6-mm and 4.0-mm diameter and on single grains. Four-millimeter aliquot minimum ages closely approximate the single-grain minimum ages and are younger than 9.6-mm aliquot minimum and central ages. Based on these results, the small-aliquot (4-mm) approach appears to provide ages comparable to those obtained by the more laborious and time-consuming single-grain method. Minimum ages indicate rapid deposition of the Homeb Silts in at least two episodes centered at ∼15 ka and ∼6 ka during climate transitions from arid to humid. Flash floods eroded the valley fills during slightly more arid conditions.

Keywords

Namib DesertHomeb SiltSedimentary environmentLuminescence dating
Type
Research Article
Information
Quaternary Research , Volume 65 , Issue 3 , May 2006 , pp. 478 - 491
Copyright
University of Washington

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.)

References

Aitken, M.J., (1998). An Introduction to Optical Dating. Academic Press, London.359 pp.CrossRefGoogle Scholar
Baker, V.R., (1987). Palaeoflood hydrology and extreme flood events. Journal of Hydrology 96, 79–99.CrossRefGoogle Scholar
Baker, V.R., Kochel, R.C., (1988). Flood sedimentation in bedrock fluvial systems. Baker, V.R., Kochel, R.C., Patton, P.C. Flood Geomorphology John Wiley, New York.123–137.Google Scholar
Bard, E., Hamelin, B., Fairbanks, R.G., Zindler, A., (1990). Calibration of the 14C timescale over the past 30,000 yr using mass spectrometric U–Th ages from Barbados corals. Nature 345, 405–410.CrossRefGoogle Scholar
Bard, E., Rostek, F., Ménot-Combes, G., (2004). Radiocarbon calibration beyond 20,000 14C yr BP by means of planktonic foraminifera of the Iberian Margin. Quaternary Research 61, 204–214.CrossRefGoogle Scholar
Benito, G., Sanchez-Moya, Y., Sopena, A., (2003). Sedimentology of high stage flood deposits of the Tagus River, Central Spain. Sedimentary Geology 157, 107–132.CrossRefGoogle Scholar
Bourke, M.C., Child, A., Stokes, S., (2003). Optical age estimates for hyper-arid fluvial deposits at Homeb, Namibia. Quaternary Science Reviews 22, 1099–1103.Google Scholar
Brook, G.A., Marais, E., Cowart, J.B., (1999). Evidence of wetter and drier conditions in Namibia from tufas and submerged speleothems. Cimbebasia 15, 29–39.Google Scholar
Clarke, M.L., (1996). IRSL dating of sands: bleaching characteristics at deposition inferred from use of single aliquots. Radiation Measurements 26, 611–620.CrossRefGoogle Scholar
Colls, A.E., Stokes, S., Blum, M.D., Straffin, E., (2001). Age limits on the late Quaternary evolution of the upper Loire River. Quaternary Science Reviews 20, 743–750.Google Scholar
Deacon, J., Lancaster, N., (1988). Late Quaternary Environments of Southern Africa. Oxford University Press, 220 pp.Google Scholar
Duller, G.A.T., (1999). Luminescence Analyst computer programme V2.18. Department of Geography and Environmental Sciences. University of Wales, Abersystwyth.Google Scholar
Eitel, B., Zöller, L., (1996). Soils and sediments in the basin of Dieprivier–Uitskot (Khoriax District, Namibia) age, geomorphic and sedimentological investigation, paleoclimatic interpretation. Palaeoecology of Africa 24, 159–172.Google Scholar
Eitel, B., Blümel, W.D., Hüser, K., 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.CrossRefGoogle Scholar
Gingele, F.X., (1996). Holocene climatic optimum in Southwest Africa–Evidence from the marine clay mineral record. Palaeogeography, Palaeoclimatology, Palaeoecology 122, 77–87.CrossRefGoogle Scholar
Goudie, A., (1972). Climate, weathering, crust formation, dunes and fluvial features of Central Namib Desert, near Gobabeb, Southwest Africa. Madoqua II 1, 54–64 15–31.Google Scholar
Heaton, T.H.E., Talma, A.S., Vogel, J.C., (1983). Origin and history of nitrate in confined groundwater in the western Kalahari. Journal of Hydrology 62, 243–262.CrossRefGoogle Scholar
Heine, K., Heine, J.T., (2002). A paleohydrologic reinterpretation of Homeb Silts, Kuiseb River, central Namib Desert (Namibia) and paleoclimatic implications. Catena 48, 107–130.Google Scholar
Hughen, K., Lehman, S., Southon, J., Overpeck, J., Marchal, O., Herring, C., Turnbull, J., (2004). 14C activity and global carbon cycle changes over the past 50,000 years. Science 303, 202–207.Google Scholar
Jacobson, P.J., Jacobson, K.M., Seely, M.K., (1995). Ephemeral Rivers and their Catchments: Sustaining People and development in Western Namibia. Desert Research Foundation of Namibia, Windhoek.160 pp.Google Scholar
Kale, V.S., Singhvi, A.K., Mishra, P.K., Banerjee, D., (2000). Sedimentary records and luminescence chronology of Late Holocene palaeofloods in the Luni River, Thar Desert, Northwest India. Catena 40, 337–358.CrossRefGoogle Scholar
Lancaster, N., (1979). Evidence for a widespread late Pleistocene humid period in the Kalahari. Nature 279, 145–146.Google Scholar
Lancaster, N., (1989). Late Quaternary palaeoenvironments in the southwestern Kalahari. Palaeogeography, Palaeoclimatology, Palaeoecology 70, 367–376.CrossRefGoogle Scholar
Marker, M.E., (1977). Aspects of the geomorphology of the Kuiseb River, South West Africa. Madoqua 10, 199–206.Google Scholar
Marker, M.E., Müller, D., (1978). Relict vlei silts of the middle Kuiseb River valley, South West Africa. Madoqua 11, 151–162.Google Scholar
Miall, A.D., (1996). The Geology of Fluvial Deposits. Springer, Berlin.582 pp.Google Scholar
Murray, A.S., Wintle, A.G., (2000). Luminescence dating of quartz using improved single-aliquot regenerative-dose protocol. Radiation Measurements 32, 57–73.CrossRefGoogle Scholar
Murray, A.S., Wintle, A.G., (2003). The single aliquot regenerative protocol: potential for improvements and reliability. Radiation Measurements 37, 377–381.Google Scholar
Ollier, C.D., (1977). Outline geological and geomorphological history of the Central Namib Desert. Madoqua 10, 3 207–212.Google Scholar
Prescott, J.R., Stephan, L.G., (1982). Contribution of cosmic radiation to environmental dose. PACT 6, 17–25.Google Scholar
Ramsey, C.B., (1995). Radiocarbon calibration and analysis of stratigraphy: the OxCal program. Radiocarbon 37, 2 425–430.Google Scholar
Ramsey, C.B., (2001). Development of the radiocarbon program OxCal. Radiocarbon 43, 2A 355–363.Google Scholar
Rust, U., Wienke, F., (1980). A reinvestigation of some aspects of the evolution of the Kuiseb River valley upstream of Gobabeb, South West Africa. Madoqua 12, 3 163–173.Google Scholar
Rust, U., Schmidt, H.H., Dietz, K.R., (1984). Palaeoenvironments of the present day arid South Western Africa 30000–5000 BP: results and problems. Palaeoecology of Africa 16, 109–148.Google Scholar
Scott, L., Cooremans, B., de Wet, J.S., Vogel, J.C., (1991). Holocene environmental changes in Namibia inferred from pollen analysis of swamp and lake deposits. The Holocene 1, 8–13.Google Scholar
Shi, N., Dupont, L.M., Beug, H.-J., Schneider, R., (2000). Correlation between vegetation in southwestern Africa and oceanic upwelling in the past 21,000 years. Quaternary Research 54, 72–80.CrossRefGoogle Scholar
Smith, R.M.H., Mason, T.R., Ward, J.D., (1993). Flash flood sediments and ichnofacies of the Late Pleistocene Homeb Silts, Kuiseb River, Namibia. Sedimentary Geology 85, 579–599.CrossRefGoogle Scholar
Srivastava, P., Brook, G.A., Marais, E., (2004). A Record of fluvial aggradation in northern Namib Desert during the Late Quaternary. Zeitschrift für Geomorphologie N.F., Suppl.-Vol. 133, 1–18.Google Scholar
Srivastava, P., Brook, G.A., Marais, E., (2005). Depositional environment and luminescence chronology of the Hoarusib River Clay Castles sediments, northern Namib Desert, Namibia. Catena 59, 187–204.Google Scholar
Stute, M., Talma, A.S., (1997). Glacial temperature and moisture transport regimes reconstructed from noble gases and *18O, Stampriet aquifer, Namibia. International Symposium on Isotope Techniques in the Study of Past and Current Environmental Changes in the Hydrosphere and the Atmosphere, Vienna, Austria. 307–318.Google Scholar
Teller, J.T., Rutter, N., Lancaster, N., (1990). Sedimentology and paleohydrology of late Quaternary lake deposits in the northern Namib Sand Sea, Namibia. Quaternary Science Reviews 9, 343–364.Google Scholar
Thomas, D.S.G., Brook, G.A., Shaw, P., Bateman, M., Haberyan, K., Appleton, C., Nash, D., McLaren, S., Davies, F., (2003). Late Pleistocene wetting and drying in the NW Kalahari: an integrated study from the Tsodilo Hills, Botswana. Quaternary International 104, 53–67.Google Scholar
Thomas, P.J., Jain, M., Juyal, N., Singhvi, A.K., (2005). Comparison of single grain and small aliquot OSL dose estimates in <3000 years old river sediments from south India. Radiation Measurement 39, 457–469.CrossRefGoogle Scholar
Van der Wateren, F.M., Dunai, T.J., (2001). Late Neogene passive margin denudation history–Cosmogenic isotope measurements from the central Namib Desert. Global and Planetary Change 30, 271–307.Google Scholar
Vogel, J.C., (1982). The age of Kuiseb River silt terrace at Homeb. Palaeoecology of Africa 15, 201–209.Google Scholar
Vogel, J.C., (1989). Evidence for past climatic change in the Namib desert. Palaeogeography, Palaeoclimatology, Palaeoecology 70, 355–366.Google Scholar
Vogel, J.C., Visser, E., (1981). Pretoria radiocarbon dates II. Radiocarbon 23, 43–80.Google Scholar
Ward, J.D., (1987). The Cenozoic succession of Kuiseb Valley, Central Namib Desert. Geological Survey of Namibia Memoir 124 pp.Google Scholar