Imperial College London
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ProfessorTinavan de Flierdt

Faculty of Engineering, Department of Earth Science & Engineering

Head of the Department of Earth Science and Engineering
 
 
 
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Contact

 

+44 (0)20 7594 1290tina.vandeflierdt

 
 
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Location

 

G.30Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Evangelinos:2020:10.1016/j.gloplacha.2020.103221,
author = {Evangelinos, D and Escutia, C and Etourneau, J and Hoem, F and Bijl, P and Boterblom, W and van, de Flierdt T and Valero, L and Flores, J-A and Rodriguez-Tovar, FJ and Jimenez-Espejo, FJ and Salabarnada, A and López-Quirós, A},
doi = {10.1016/j.gloplacha.2020.103221},
journal = {Global and Planetary Change},
title = {Late Oligocene-Miocene proto-Antarctic Circumpolar Current dynamics off the Wilkes Land margin, East Antarctica},
url = {http://dx.doi.org/10.1016/j.gloplacha.2020.103221},
volume = {191},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - At present, the Southern Ocean plays an important role in the global climate system and in modern Antarctic ice sheet dynamics. Past Southern Ocean configurations are however poorly understood. This information is yet important as it may provide important insights into the climate system and past ice-sheet behavior under warmer than present day climates. Here we study Southern Ocean dynamics during the Oligocene and Miocene when reconstructed atmospheric CO2 concentrations were similar to those expected during this century. We reconstruct snapshots of late Oligocene to earliest Miocene (~24.2–23 Ma) paleoceanographic conditions in the East Antarctic Wilkes Land abyssal plain. For this, we combine marine sedimentological, geochemical (X-ray fluorescence, TEX86,), palynological and isotopic (εNd) records from ocean sediments recovered at Deep Sea Drilling Project (DSDP) Site 269. Overall, we find that sediments, delivered to the site by gravity flows and hemipelagic settling during glacial-interglacial cycles, were persistently reworked by a proto-Circumpolar Deep Water (CDW) with varying strengths that result from climatically controlled frontal system migrations. Just prior to 24 Ma, terrigenous input of predominantly fine-grained sediments deposited under weak proto-CDW intensities and poorly ventilated bottom conditions dominates. In comparison, 24 Ma marks the start of episodic events of enhanced proto-CDW current velocities, associated with coarse-grained deposits and better-ventilated bottom conditions. In particular, the dominance of P-cyst and low Calcium (Ca) in the sediments between ~ 24.2 Ma and 23.6 Ma indicate the presence of an active open ocean upwelling associated with high nutrient conditions. This is supported by TEX86-derived sea surface temperature (SST) data pointing to cool ocean conditions. From ~ 23.6 to 23.2 Ma, our records reveal an enrichment of Ca in the sediments related to increased calcareous microfossil preservation, high
AU  - Evangelinos,D
AU  - Escutia,C
AU  - Etourneau,J
AU  - Hoem,F
AU  - Bijl,P
AU  - Boterblom,W
AU  - van,de Flierdt T
AU  - Valero,L
AU  - Flores,J-A
AU  - Rodriguez-Tovar,FJ
AU  - Jimenez-Espejo,FJ
AU  - Salabarnada,A
AU  - López-Quirós,A
DO  - 10.1016/j.gloplacha.2020.103221
PY  - 2020///
SN  - 0921-8181
TI  - Late Oligocene-Miocene proto-Antarctic Circumpolar Current dynamics off the Wilkes Land margin, East Antarctica
T2  - Global and Planetary Change
UR  - http://dx.doi.org/10.1016/j.gloplacha.2020.103221
UR  - http://hdl.handle.net/10044/1/80548
VL  - 191
ER  -
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