@article{207f6571f0194a48a1286f7742d76359,
title = "A large West Antarctic Ice Sheet explains early Neogene sea-level amplitude",
abstract = "Early to Middle Miocene sea-level oscillations of approximately 40–60 m estimated from far-field records1–3 are interpreted to reflect the loss of virtually all East Antarctic ice during peak warmth2. This contrasts with ice-sheet model experiments suggesting most terrestrial ice in East Antarctica was retained even during the warmest intervals of the Middle Miocene4,5. Data and model outputs can be reconciled if a large West Antarctic Ice Sheet (WAIS) existed and expanded across most of the outer continental shelf during the Early Miocene, accounting for maximum ice-sheet volumes. Here we provide the earliest geological evidence proving large WAIS expansions occurred during the Early Miocene (~17.72–17.40 Ma). Geochemical and petrographic data show glacimarine sediments recovered at International Ocean Discovery Program (IODP) Site U1521 in the central Ross Sea derive from West Antarctica, requiring the presence of a WAIS covering most of the Ross Sea continental shelf. Seismic, lithological and palynological data reveal the intermittent proximity of grounded ice to Site U1521. The erosion rate calculated from this sediment package greatly exceeds the long-term mean, implying rapid erosion of West Antarctica. This interval therefore captures a key step in the genesis of a marine-based WAIS and a tipping point in Antarctic ice-sheet evolution.",
author = "Marschalek, {J. W.} and L. Zurli and F. Talarico and {van de Flierdt}, T. and P. Vermeesch and A. Carter and Fran{\c c}ois Beny and V. Bout-Roumazeilles and Francesca Sangiorgi and Hemming, {S. R.} and P{\'e}rez, {L. F.} and F. Colleoni and Prebble, {J. G.} and {van Peer}, {T. E.} and M. Perotti and Shevenell, {A. E.} and I. Browne and Kulhanek, {Denise K.} and R. Levy and D. Harwood and Sullivan, {N. B.} and Meyers, {S. R.} and Griffith, {E. M.} and Hillenbrand, {C. D.} and {IODP Expedition 374} and E. Gasson and Siegert, {M. J.} and B. Keisling and Licht, {K. J.} and G. Kuhn and Dodd, {J. P.} and C. Boshuis and {De Santis}, Laura and McKay, {Robert M.} and Jeanine Ash and Fran{\c c}ois Beny and Browne, {Imogen M.} and Giuseppe Cortese and {De Santis}, Laura and Dodd, {Justin P.} and Esper, {Oliver M.} and Gales, {Jenny A.} and Harwood, {David M.} and Saki Ishino and Keisling, {Benjamin A.} and Sookwan Kim and Sunghan Kim and Kulhanek, {Denise K.} and Laberg, {Jan Sverre} and Leckie, {R. Mark}",
note = "Funding Information: Acknowledgements This research used data and samples provided by the International Ocean Discovery Program (IODP), which is sponsored by the US National Science Foundation (NSF) and participating countries under the management of Joint Oceanographic Institutions. J.W.M. was supported by a NERC DTP studentship (grant number NE/L002515/1). Neodymium and Sr isotope analysis and U–Pb dating of detrital zircons was funded through NERC UK IODP grant NE/R018219/1. Clast counts performed by L.Z., F.T. and M.P. and the participation of L.D. and F.C. was funded by the Italian National Antarctic Research Program (PNRA, Programma Nazionale Ricerche in Antartide), grant numbers PNRA18-00233, PNRA16-00016 and PNRA18-00002. R.M.M. was supported by Royal Society Te Apārangi Marsden Fund (18-VUW-089). R.M.M., J.G.P. and R.L. were supported by the New Zealand Ministry for Business Innovation and Employment grant ANTA1801. P.V. was partially funded by NERC Standard Grant NE/T001518/1. L.F.P. has been funded by the European Union{\textquoteright}s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 792773 WAMSISE. T.E.v.P. has been funded by NERC grants NE/R018235/1 and NE/T012285/1. D.K.K. was supported by the IODP JOIDES Resolution Science Operator and National Science Foundation (grant numbers OCE-1326927 and OPP-2000995). A.E.S. and I.B. were supported by the US Science Support Program. Southern Transantarctic Mountain rock samples for Nd and Sr isotope analysis were provided by the Polar Rock Repository with support from the National Science Foundation, under Cooperative Agreement OPP-1643713. We thank B. Coles, K. Kreissig and P. Sim{\~o}es Pereira for technical support. We also thank the numerous scientists who collected invaluable site survey data and developed the proposals and hypotheses that ultimately led to IODP Expedition 374. Expedition 374 was conducted under Antarctic Conservation Act Permit Number: ACA 2018-027 (permit holder: Bradford Clement, JRSO, IODP, TAMU, College Station, TX 77845). Publisher Copyright: {\textcopyright} 2021, The Author(s), under exclusive licence to Springer Nature Limited.",
year = "2021",
month = dec,
day = "16",
doi = "10.1038/s41586-021-04148-0",
language = "English",
volume = "600",
pages = "450--455",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Research",
number = "7889",
}