Strengthening of North American dust sources during the late Pliocene (2.7 Ma)

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doi: 10.1016/j.epsl.2011.11.026
Author(s): Naafs, B. David A.; Hefter, Jens; Acton, Gary; Haug, Gerald H.; Martinez-Garcia, Alfredo; Pancost, Richard; Stein, Ruediger
Author Affiliation(s): Primary:
Alfred Wegener Institute for Polar and Marine Research, Department of Marine Geology and Paleontology, Bremerhaven, Germany
Potsdam University, Germany
University of California, Davis, United States
University of Bristol, United Kingdom
Volume Title: Earth and Planetary Science Letters
Source: Earth and Planetary Science Letters, Vol.317-318, p.8-19. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0012-821X CODEN: EPSLA2
Note: In English. Supplementary data available in online version. 115 refs.; illus.
Summary: Here we present orbitally-resolved records of terrestrial higher plant leaf wax input to the North Atlantic over the last 3.5 Ma, based on the accumulation of long-chain n-alkanes and n-alkanl-1-ols at IODP Site U1313. These lipids are a major component of dust, even in remote ocean areas, and have a predominantly aeolian origin in distal marine sediments. Our results demonstrate that around 2.7 million years ago (Ma), coinciding with the intensification of the Northern Hemisphere glaciation (NHG), the aeolian input of terrestrial material to the North Atlantic increased drastically. Since then, during every glacial the aeolian input of higher plant material was up to 30 times higher than during interglacials. The close correspondence between aeolian input to the North Atlantic and other dust records indicates a globally uniform response of dust sources to Quaternary climate variability, although the amplitude of variation differs among areas. We argue that the increased aeolian input at Site U1313 during glacials is predominantly related to the episodic appearance of continental ice sheets in North America and the associated strengthening of glaciogenic dust sources. Evolutional spectral analyses of the n-alkane records were therefore used to determine the dominant astronomical forcing in North American ice sheet advances. These results demonstrate that during the early Pleistocene North American ice sheet dynamics responded predominantly to variations in obliquity (41 ka), which argues against previous suggestions of precession-related variations in Northern Hemisphere ice sheets during the early Pleistocene. Abstract Copyright (2012) Elsevier, B.V.
Year of Publication: 2012
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 06 Petrology, Sedimentary; 12 Stratigraphy, Historical Geology and Paleoecology; Aliphatic hydrocarbons; Alkanes; Atlantic Ocean; Biomarkers; C-13/C-12; Carbon; Cenozoic; Clastic sediments; Dust; Expedition 306; Expeditions 303/306; Glacial geology; Glaciation; Hydrocarbons; IODP Site U1313; Ice sheets; Integrated Ocean Drilling Program; Isotope ratios; Isotopes; Leaves; Lipids; Marine sediments; Mass spectra; Mid-Atlantic Ridge; Milankovitch theory; N-alkanes; Neogene; North America; North Atlantic; Obliquity of the ecliptic; Organic compounds; Paleoclimatology; Plantae; Pleistocene; Pliocene; Precession; Provenance; Quaternary; Sediments; Spectra; Stable isotopes; Terrestrial environment; Tertiary; Transport; Upper Pliocene; Waxes; Wind transport
Coordinates: N410000 N410000 W0325700 W0325700
Record ID: 2012051960
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands