1. A plio-pleistocene (C. 0–4 ma) cyclostratigraphy for iodp site u1478 (mozambique channel, sw indian ocean): Exploring an offshore record of paleoclimate and ecosystem variability in se africa
- Author
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Koutsodendris, Andreas, Nakajima, Kai, Kaboth-Bahr, Stefanie, Berke, Melissa A., Franzese, Allison M., Hall, Ian R., Hemming, Sidney R., Just, Janna, Levay, Leah J., Pross, Jörg, Robinson, Rebecca, Barker, S., Brentegani, L., Caley, T., Cartagena-Sierra, A., Charles, C. D., Coenen, J. J., Crespin, J. G., Gruetzner, J., Han, X., Hines, S. K.V., Espejo, F. J. Jimenez, Kubota, K., Lathika, N., Norris, R. D., Dos Santos, T. Pereira, Rolinson, J. M., Simon, M. H., Tangunan, D., van der Lubbe, J. J.L., Yamane, M., Zhang, H., Koutsodendris, Andreas, Nakajima, Kai, Kaboth-Bahr, Stefanie, Berke, Melissa A., Franzese, Allison M., Hall, Ian R., Hemming, Sidney R., Just, Janna, Levay, Leah J., Pross, Jörg, Robinson, Rebecca, Barker, S., Brentegani, L., Caley, T., Cartagena-Sierra, A., Charles, C. D., Coenen, J. J., Crespin, J. G., Gruetzner, J., Han, X., Hines, S. K.V., Espejo, F. J. Jimenez, Kubota, K., Lathika, N., Norris, R. D., Dos Santos, T. Pereira, Rolinson, J. M., Simon, M. H., Tangunan, D., van der Lubbe, J. J.L., Yamane, M., and Zhang, H.
- Abstract
The paleoclimate and ecosystem variability in Africa during the Plio/Pleistocene has received considerable attention due to its potential links to hominid evolution. However, the reconstruction of this variability hinges critically upon highly temporally resolved proxy data from continuous, well-dated sediment archives. In light of these requirements we use a new XRF core-scanning record from International Ocean Discovery Program (IODP) Site U1478 off the Limpopo River mouth (Mozambique Channel, SW Indian Ocean) spanning the past c. 4 Ma to identify the climate variability in SE Africa. Our results show that the elemental distribution in the Site U1478 cores is mainly controlled by the rate of terrigenous input and – to a lesser extent – by bottom-current transport and post-depositional processes such as propagation of paleoredox boundaries and diagenesis across some intervals. The log(Ti/Ca) ratio, which is used as a tracer of terrigenous sediment input, shows quasi-cyclical variability across the entire record that closely matches the periods of orbital parameters. However, the cyclical behaviour of the log(Ti/Ca) signal varies through time, with the uppermost 106 m of the sequence (0–1.07 Ma) displaying a mix of precession and obliquity signals, the intervals 106–223 m (1.07–2.80 Ma) and 240–257 m (3.68–4.05 Ma) being dominated by precession, and the interval 223–240 m (2.80–3.68 Ma) being controlled by eccentricity. To refine the available chronology for Site U1478, which is based on shipboard biostratigraphic and paleomagnetic data, we have tuned the log(Ti/Ca) record to the LR04 benthic oxygen isotope record, summer insolation at 25° S, and orbital eccentricity depending on the dominant cyclicities in the XRF dataset across individual time intervals. The resulting chronology enables us to evaluate the XRF data as well as the previously available shipboard sedimentological and geochemical datasets within a regional and global climatic context. This allows the c
- Published
- 2021