Byrd Ice Core Debris Constrains the Sediment Provenance Signature of Central West Antarctica

• Main Authors: Marschalek, J. W., Blard, Pierre-Henri, Sarigulyan, E., Ehrmann, Werner, Hemming, S. R., Thomson, S. N., Hillenbrand, Claus Dieter, Licht, Kathy, Tison, Jean-Louis, Ardoin, Lisa, Fripiat, François, Allen, C. S., Marrocchi, Yves, Siegert, Martin J., van de Flierdt, Tina
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2024
• Subjects: Sciences exactes et naturelles; Antarctic; West Antarctica; West Antarctic Ice Sheet; Byrd; Antarc*; Antarctica; ice core; Ice Sheet
• Online Access: http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/373648; https://dipot.ulb.ac.be/dspace/bitstream/2013/373648/3/Marschalek_et_al_2024GRL.pdf

Abstract Provenance records from sediments deposited offshore of the West Antarctic Ice Sheet (WAIS) can help identify past major ice retreat, thus constraining ice‐sheet models projecting future sea‐level rise. Interpretations from such records are, however, hampered by the ice obscuring Antarctica's geology. Here, we explore central West Antarctica's subglacial geology using basal debris from within the Byrd ice core, drilled to the bed in 1968. Sand grain microtextures and a high kaolinite content (∼38–42%) reveal the debris consists predominantly of eroded sedimentary detritus, likely deposited initially in a warm, pre‐Oligocene, subaerial environment. Detrital hornblende 40 Ar/ 39 Ar ages suggest proximal late Cenozoic subglacial volcanism. The debris has a distinct provenance signature, with: common Permian‐Early Jurassic mineral grains; absent early Ross Orogeny grains; a high kaolinite content; and high 143 Nd/ 144 Nd and low 87 Sr/ 86 Sr ratios. Detecting this “fingerprint” in Antarctic sedimentary records could imply major WAIS retreat, revealing the WAIS's sensitivity to future warming. info:eu-repo/semantics/published