Thorium-derived dust fluxes to the tropical Pacific Ocean, 58 Ma

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doi: 10.1016/j.gca.2012.03.035
Author(s): Woodard, S. C.; Thomas, D. J.; Marcantonio, F.
Author Affiliation(s): Primary:
Texas A&M University, Department of Oceanography, College Station, TX, United States
Volume Title: Geochimica et Cosmochimica Acta
Source: Geochimica et Cosmochimica Acta, Vol.87, p.194-209. Publisher: Elsevier, New York, NY, International. ISSN: 0016-7037 CODEN: GCACAK
Note: In English. Includes appendices. 121 refs.; illus., incl. 3 tables
Summary: Eolian dust in pelagic deep sea sediments can be used to reconstruct ancient wind patterns and paleoenvironmental response to climate change. Traditional methods to determine dust accumulation involve isolating the non-dissolvable aluminosilicate minerals from deep sea sediments through a series of chemical leaches, but cannot differentiate between minerals from eolian, authigenic and volcanogenic sources. Other geochemical proxies, such as sedimentary 232Th and crustal 4He content, have been used to construct high-resolution records of atmospheric dust fluxes to the deep sea during the Quaternary. Here we use sedimentary Th content as a proxy for terrigenous material (eolian dust) in ≈58 Myr-old sediments from the Shatsky Rise (ODP Site 1209) and compare our results with previous dust estimates generated using the traditional chemical extraction method and sedimentary 4Hecrustal concentrations. We find excellent agreement between Th-based dust estimates and those generated using the traditional method. In addition our results show a correlation between sedimentary Th and 4Hecrustal content, which suggests a source older than present day Asian loess supplied dust to the central subtropical Pacific Ocean during the early Paleogene. Abstract Copyright (2012) Elsevier, B.V.
Year of Publication: 2012
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 06 Petrology, Sedimentary; Actinides; Cenozoic; Chemical composition; Clastic sediments; Climate change; DSDP Site 463; Deep Sea Drilling Project; Dust; East Pacific; Equatorial Pacific; Geochemistry; He-4; Helium; IPOD; Isotopes; Leg 130; Leg 138; Leg 198; Leg 199; Leg 62; Marine sedimentation; Marine sediments; Metals; Mid-Pacific Mountains; Noble gases; North Pacific; Northeast Pacific; Northwest Pacific; ODP Site 1209; ODP Site 1215; ODP Site 806; ODP Site 849; Ocean Drilling Program; Ontong Java Plateau; Pacific Ocean; Paleocene; Paleoclimatology; Paleoenvironment; Paleogene; Pelagic environment; Quaternary; Radioactive isotopes; Sedimentation; Sedimentation rates; Sediments; Shatsky Rise; Stable isotopes; Tertiary; Th-232; Thorium; Tropical environment; West Pacific
Coordinates: N323900 N324000 E1583100 E1583000
Record ID: 2012078565
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands