Southern Greenland glaciation and Western Boundary Undercurrent evolution recorded on Eirik Drift during the late Pliocene intensification of Northern Hemisphere glaciation

• Published in: Quaternary Science Reviews
• Main Authors: Blake-Mizen, K, Hatfield, R, Stoner, J, Carlson, A, Xuan, C, Walczak, M, Lawrence, K, Channell, J, Bailey, I
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2019
• Subjects: Plio-Pleistocene transition; Glaciation; Paleoclimatology; Paleoceanography; Paleomagnetism; Greenland; North Atlantic; Ice-rafted debris; Relative paleointensity
• Online Access: http://hdl.handle.net/10871/35602; https://doi.org/10.1016/j.quascirev.2019.01.015

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record. We present new sedimentological and environmental magnetic records spanning ~3.2–2.2 Ma, during the intensification of Northern Hemisphere glaciation, from North Atlantic Integrated Ocean Drilling Program Site U1307 on Eirik Drift. Our new datasets and their high-fidelity age control demonstrate that while inland glaciers – and potentially also at times restricted marine-terminating ice-caps – have likely existed on southern Greenland since at least ~3.2 Ma, persistent and extensive marine-terminating glacial margins were only established in this region at 2.72 Ma, ~300 kyr later than in northeastern and eastern Greenland. Despite a dramatic increase in Greenland-sourced ice-rafted debris deposition on Eirik Drift at this time, contemporaneous changes in the bulk magnetic properties of Site U1307 sediments, and a reduction in sediment accumulation rates, suggest a decrease in the delivery of Greenland-sourced glaciofluvial silt, which we attribute to a shift in depositional regime from bottom-current-dominated to glacial-IRD- dominated between ~2.9–2.7 Ma in response to a change in the depth of the flow path of the Western Boundary Undercurrent relative to our study site.