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Geochemical trends through time and lateral variability of diatom floras in the Pleistocene Olorgesailie Formation, southern Kenya Rift Valley

Published online by Cambridge University Press:  20 January 2017

R. B. Owen*
Affiliation:
Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong
R. W. Renaut
Affiliation:
Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatachewan S7N 5E2, Canada
R. Potts
Affiliation:
Human Origins Program, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, Washington D.C. 20013–7012, USA Paleontology Section, Department of Earth Sciences, National Museums of Kenya, P.O. Box 40658, Nairobi, Kenya
A. K. Behrensmeyer
Affiliation:
Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, Washington D.C. 20013, USA
*
Corresponding author. E-mail address:[email protected] (R. Potts), [email protected] (R.W. Renaut), [email protected], [email protected] (A.K. Behrensmeyer).

Abstract

The Olorgesailie Formation (1.2–0.49 Ma) consists of fluvial and lacustrine rift sediments that have yielded abundant Acheulean artifacts and a fossil hominin (Homo cf. erectus). In testing prior understandings of the paleoenvironmental context, we define nine new geochemical zones. A Chemical Index of Alteration suggests increased catchment weathering during deposition of Members 1, 2, 7, 11, and 13. Biophile elements (Br, S) peak in M8–9 and lower M13 possibly reflecting increased input from soil erosion. REE data show that the Magadi Trachytes supplied most siliciclastic grains. Sixteen diatom stages indicate conductivities of 200–16,000 μS cm− 1 and pH of 7.5–9.5 for five deep-water lakes, ten shallow lakes and sixteen wetlands. These results are compared with diatom data from other sections in the basin and show aquatic spatial variability over km-scale distances. Similar floras are traceable over several kilometers for M2, M3 and M9, indicating broadly homogeneous lacustrine conditions during these times, but diatoms in other members imply variable conditions, some related to local tectonic controls. This lateral and temporal variability emphasizes the importance of carrying out stratigraphic sampling at multiple sites within a basin in efforts to define the environmental context relevant to human evolution.

Type
Research Article
Copyright
University of Washington

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References

Alvisi, F., and Dinelli, E. Evolution of sediment composition of the coastal Lake San Puoto (Latium, Italy) in the last two centuries. Journal of Limnology 61, (2002). 1526.Google Scholar
Ashley, G.M. Orbital rhythms, monsoons, and playa lake response, Olduvai Basin, equatorial East Africa (ca. 1.85–1.74 Ma). Geology 35, (2007). 10911094.Google Scholar
Ashley, G.M., and Driese, S.G. Paleopedology and paleohydrology of a volcaniclastic paleosol interval: Implications for early Pleistocene stratigraphy and paleoclimate record, Olduvai Gorge, Tanzania. Journal of Sedimentary Research 70, (2000). 10651080.CrossRefGoogle Scholar
Baker, B.H. Geology of the Magadi Area: Geological Survey of Kenya Report No. 42. (1958). 81 pp.Google Scholar
Behrensmeyer, A., Potts, R., Deino, A., and Ditchfield, P. Olorgesailie, Kenya: a million years in the life of a rift basin. Renaut, R.W., and Ashley, G.M. Sedimentation in Continental Rifts. SEPM Special Publication 73, (2002). 97106.Google Scholar
Cosgrove, M.E. Iodine in the bituminous Kimmeridge Shales of the Dorset Coast. Geochimica et Cosmochimica Acta 34, (1970). 830836.Google Scholar
Crossley, R., and Knight, R.M. Volcanism in the western part of the Rift Valley in southern Kenya. Bulletin of Volcanology 44, (1981). 117128.CrossRefGoogle Scholar
Deino, A., and Potts, R. Single-crystal 40Ar/39Ar dating of the Olorgesailie Formation, southern Kenya Rift. Journal of Geophysical Research 95, (1990). 84538470.CrossRefGoogle Scholar
Deocampo, D.M., Behrensmeyer, A.K., and Potts, R. Ultrafine clay minerals of the Pleistocene Olorgesailie Formation, southern Kenya rift: diagenesis and paleoenvironments of early hominins. Clays and Clay Minerals 58, (2010). 294310.Google Scholar
Gasse, F. Les diatomées lacustres plio-pléistocènes du Gadeb (Ethiopie): systématique, paléoécologie, biostratigraphie. Revue d'Algologie 3, (1980). 1249.Google Scholar
Gasse, F. East African diatoms. Taxonomy, ecological distribution. Bibliotheca Diatomologica, vol. 11. (1986). J. Cramer, Stuttgart. 202 pp.Google Scholar
Hay, R.L., and Kyser, T.K. Chemical sedimentology and palaeoenvironmental history of Lake Olduvai, a Pliocene lake in northern Tanzania. Geological Society of America Bulletin 113, (2001). 15051521.2.0.CO;2>CrossRefGoogle Scholar
Isaac, G.L. The Olorgesailie Formation: stratigraphy, tectonics and the palaeogeographic context of the Middle Pleistocene archaeological sites. Bishop, W.W. Geological Background to Fossil Man. (1978). Scottish Academic Press, Edinburgh. 173206.Google Scholar
Jin, Z., Wang, S., Shen, J., Zhang, E., Li, F., Ji, J., and Lu, X. Chemical weathering since the Little Ice Age recorded in lake sediments: a high resolution proxy of past climate. Earth Surface Processes and Landforms 26, (2001). 775782.Google Scholar
Kilham, P., and Kilham, S.S. Melosira granulata (Ehr.) Ralfs: morphology and ecology of a cosmopolitan freshwater diatom. Verhandlungen des Internationalen Verein Limnologie 19, (1971). 27162721.Google Scholar
Koinig, K.A., Shotyk, W., Lotter, A.F., Ohlendorf, C., and Sturm, M. 9000 years of geochemical evolution of lithogenic major and minor trace elements in the sediment of an alpine lake — the role of climate, vegetation, and land-use history. Journal of Paleolimnology 30, (2003). 307320.Google Scholar
Krammer, K., and Lange-Bertalot, H. Bacillariophyceae 3. Centrales, Fragilariaceae, Eunotiaceae. Ettl, H., Gerloff, J., Heyning, H., and Mollenhauer, D. Susswasserflora von Mitteleuropa 2/1 G. (1991). Fisher Verlag, Jena. 600 Google Scholar
Le Roux, A.P., Späth, A., and Zartman, R.E. Lithospheric thickness beneath the southern Kenya Rift: implications from basalt geochemistry. Contributions to Mineralogy and Petrology 142, (2001). 89106.CrossRefGoogle Scholar
Legesse, D., Gasse, F., Radakovitch, O., Vallet-Coulomb, C., Bonnefille, R., Verschuren, D., Gibert, E., and Barker, P. Environmental changes in a tropical lake (Lake Abiyata, Ethiopia) during recent centuries. Palaeogeography, Palaeoclimatology, Palaeoecology 187, (2002). 233258.CrossRefGoogle Scholar
Maslin, M.A., and Christensen, B. Tectonics, orbital forcing, global climate change, and human evolution in Africa: introduction to the African paleoclimate special volume. Journal of Human Evolution 53, (2007). 443464.Google Scholar
McDonald, R., Rogers, N.W., Fitton, J.G., Black, S., and Smith, M. Plume-lithosphere interactions in the generation of the basalts of the Kenya Rift, East Africa. Journal of Petrology 42, (2001). 877900.CrossRefGoogle Scholar
McLennan, S.M. Rare Earth Elements in sedimentary rocks: influence of the provenance and sedimentary process. Reviews in Mineralogy and Geochemistry 21, (1989). 169200.Google Scholar
McLennan, S.M., Hemming, S., McDaniel, D.K., and Hanson, G.N. Geochemical approaches to sedimentation, provenance, and tectonics. Johnsson, M.J., and Basu, A. Processes Controlling the Composition of Clastic sediments: Boulder, Colorado. Geological Society of America Special Paper 284, (1993). 2140.Google Scholar
Moreno, A., Giralt, S., Velero-Garcés, B., Sáez, , Bao, R., Prego, R., Pueyo, J.J., González-Sampériz, P., and Taberner, C. A 14 Kyr record of the tropical Andes: the Lago Chungará sequence (18ºS, northern Chilean Altiplano). Quaternary International 161, (2007). 421.Google Scholar
Nesbitt, H.W., and Young, G.M. Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature 299, (1982). 715717.CrossRefGoogle Scholar
Nesbitt, H.W., and Young, G.M. Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations. Geochimica et Cosmochimica Acta 48, (1984). 15231534.Google Scholar
Oldfield, F., Wake, R., Boyle, J., Jones, R., Nolan, S., Gibbs, Z., Appleby, P., Fisher, E., and Wolffe, G. The late-Holocene history of Gormire Lake (NE England) and its catchment: a multiproxy reconstruction of past human impact. The Holocene 13, (2003). 677690.Google Scholar
Owen, R.B. Sedimentological characteristics and origins of diatomaceous deposits in the East African Rift System. Renaut, R.W., and Ashley, G.M. Sedimentation in Continental Rifts. SEPM Special Publication 73, (2002). 233246.Google Scholar
Owen, R.B., Potts, R., Behrensmeyer, A.K., and Ditchfield, P. Diatomaceous sediments and environmental change in the Pleistocene Olorgesailie Formation, southern Kenya Rift Valley. Palaeogeography, Palaeoclimatology, Palaeoecology 269, (2008). 1737.Google Scholar
Owen, R.B., Renaut, R.W., Scott, J.J., Potts, R., and Behrensmeyer, A.K. Wetland sedimentation and associated diatoms in the Pleistocene Olorgesailie Basin, southern Kenya Rift Valley. Sedimentary Geology 222, (2009). 124137.CrossRefGoogle Scholar
Owen, R.B., Potts, R., and Behrensmeyer, A.K. Reply to the comment on “Diatomaceous sediments and environmental change in the Pleistocene Olorgesailie Formation, southern Kenya Rift Valley”. Palaeogeography, Palaeoclimatology, Palaeoecology 282, (2009). 147148.Google Scholar
Phedorin, M.A., Fedotov, A.P., Vorobieva, S.S., and Ziborova, G.A. Signature of long supercycles in the Pleistocene history of limnic systems. Journal of Paleolimnology 40, (2008). 445452.CrossRefGoogle Scholar
Potts, R. Variability selection in hominid evolution. Evolutionary Anthropology 7, (1998). 8196.3.0.CO;2-A>CrossRefGoogle Scholar
Potts, R., Behrensmeyer, A.K., and Ditchfield, P. Paleolandscape variation and early Pleistocene hominid activities: Members 1 and 7, Olorgesailie Formation. Journal of Human Evolution 37, (1999). 747788.Google Scholar
Potts, R., Behrensmeyer, A.K., Deino, A., Ditchfield, P., and Clark, J. Small mid-Pleistocene hominin associated with East African Acheulean technology. Science 305, (2004). 7578.Google Scholar
Quinn, R.L., Lepre, C.L., Wright, J.D., and Feibel, C.S. Paleogeographic variations of pedogenic carbonate δ13C values from Koobi Fora, Kenya: implications for floral compositions of Plio-Pleistocene hominin environments. Journal of Human Evolution 53, (2007). 560573.CrossRefGoogle ScholarPubMed
Sikes, N.E., Potts, R., and Behrensmeyer, A.K. Early Pleistocene habitat in Member 1 Olorgesailie based on paleosol stable isotopes. Journal of Human Evolution 37, (1999). 721746.Google Scholar
Sun, S.-S., and McDonough, W.F. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. Saunders, A.D., and Norry, M.J. Magmatism in the Ocean Basins. Geological Society, London, Special Publication 42, (1989). 313345.CrossRefGoogle Scholar
Trauth, M.H., and Maslin, M.A. Comment on “Diatomaceous sediments and environmental change in the Pleistocene Olorgesailie Formation, southern Kenya Rift Valley. Owen, R.B., Potts, R., Behrensmeyer, A.K., Ditchfield, P. Palaeogeography, Palaeoclimatology, Palaeoecology 282, (2009). 145146.Google Scholar
Trauth, M.H., Maslin, M.A., Deino, A.L., and Strecker, M.R. High- and low-latitude forcing of Plio-Pleistocene East African climate and human evolution. Journal of Human Evolution 53, (2007). 475486.Google Scholar
Trueman, C.N., Behrensmeyer, A.K., Potts, R., and Tuross, N. High-resolution records of location and stratigraphic provenance from the rare earth element composition of fossil bones. Geochimica et Cosmochimica Acta 70, (2006). 4344355.Google Scholar
Vinogradov, A.P. The Geochemistry of Rare and Dispersed Chemical Elements in Soils. 2nd edition (1959). Consultant Bureau, New York.Google Scholar
Vrba, E.S. On the connections between paleoclimate and evolution. Vrba, E.S., Denton, G.H., Partridge, T.C., and Burckle, L.H. Paleoclimate and Evolution with Emphasis on Human Origins. (1995). Yale University Press, New Haven. 2445.Google Scholar
Young, G.M., and Nesbitt, H.W. Processes controlling the distribution of Ti and Al in weathering profiles, siliciclastics sediments and sedimentary rocks. Journal of Sedimentary Research 68, (1998). 448455.CrossRefGoogle Scholar
Zhmodik, S.M., Verkhovtseva, N.V., Soloboeva, E.V., Mironov, A.G., Nemirovskaya, N.A., Ilic, R., Khlystov, O.M., and Titov, A.T. The study of distribution and forms of uranium occurrences in Lake Baikal sediments by the SSNTD method. Radiation Measurements 40, (2005). 532538.Google Scholar
Zhou, H., Wang, B.-S., Guan, H., Lai, Y.-J., and You, C.-F. Constraints from strontium and neodymium isotopic ratios and trace elements on the sources of the sediments in Lake Huguang Maar. Quaternary Research 72, (2009). 289300.Google Scholar