Flux and provenance of ice-rafted debris in the earliest Pleistocene sub-polar North Atlantic Ocean comparable to the last glacial maximum

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doi: 10.1016/j.epsl.2012.05.034
Author(s): Bailey, Ian; Foster, Gavin L.; Wilson, Paul A.; Jovane, Luigi; Storey, Craig D.; Trueman, Clive N.; Becker, Julia
Author Affiliation(s): Primary:
University of Southampton, National Oceanography Centre Southampton, Southampton, United Kingdom
Other:
University of Portsmouth, United Kingdom
Cardiff University, United Kingdom
Volume Title: Earth and Planetary Science Letters
Source: Earth and Planetary Science Letters, Vol.341-344, p.222-233. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0012-821X CODEN: EPSLA2
Note: In English. Supplementary data available in online version. 67 refs.; illus., incl. geol. sketch map
Summary: Relatively little is known in detail about the locations of the early Pleistocene ice-sheets responsible for ice-rafted debris (IRD) inputs to the sub-polar North Atlantic Ocean during intensification of northern hemisphere glaciation (iNHG). To shed new light on this problem, we present the first combined in-depth analysis of IRD flux and geochemical provenance of individual sand-sized IRD deposited in the sub-polar North Atlantic Ocean during the earliest large amplitude Pleistocene glacial, marine isotope stage (MIS) 100 (∼2.52 Ma), arguably the key glacial during iNHG. IRD provenance is assessed using laser ablation lead (Pb) isotope analyses of single feldspar grains. We find that the Pb-isotope composition (206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb) of individual ice-rafted (>150µm) feldspars deposited at DSDP Site 611A, ODP Site 981 and IODP Site U1308 during MIS 100 records a shift from predominantly Archaean-aged circum-North Atlantic Ocean continental sources during early glacial ice-rafting events to dominantly Palaeozoic and Proterozoic-aged sources during full glacial conditions. The distribution of feldspars in Pb-Pb space for full glacial MIS 100 more closely resembles that documented for feldspars deposited at the centre of the last glacial IRD belt (at IODP/DSDP Site U1308/609) during ambient (non-Heinrich-event) ice-rafting episodes of MIS 2 (∼23.8 ka) than that documented for MIS 5d (∼106 ka). Comparison of our early Pleistocene and last glacial cycle datasets suggests that MIS 100 was characterised by abundant iceberg calving from large ice-sheets on multiple continents in the high northern latitudes (not just on Greenland). Abstract Copyright (2012) Elsevier, B.V.
Year of Publication: 2012
Research Program: DSDP Deep Sea Drilling Project
IODP Integrated Ocean Drilling Program
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Atlantic Ocean; Calving; Cenozoic; DSDP Site 611; Deep Sea Drilling Project; Detritus; Expedition 303; Expeditions 303/306; Feldspar group; Framework silicates; Glacial geology; Glaciation; IODP Site U1308; IPOD; Ice rafting; Ice sheets; Icebergs; Integrated Ocean Drilling Program; Isotopes; Laser ablation; Laser methods; Last glacial maximum; Lead; Leg 162; Leg 94; Lower Pleistocene; Metals; Mid-Atlantic Ridge; North Atlantic; Northeast Atlantic; ODP Site 981; Ocean Drilling Program; Pleistocene; Provenance; Quaternary; Rockall Bank; Sediment transport; Silicates; Transport
Coordinates: N495300 N495300 W0241400 W0241400
N525009 N525029 W0301834 W0301906
N552838 N552838 W0143903 W0143903
Record ID: 2013013396
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands