Article
 

Dust, volcanic ash, and the evolution of the South Pacific Gyre through the Cenozoic

Pubblico Deposited

Contenuto scaricabile

Scarica il pdf
https://ir.library.oregonstate.edu/concern/articles/5h73q160m

Descriptions

Attribute NameValues
Creator
Abstract
  • We examine the 0–100 Ma paleoceanographic record retained in pelagic clay from the South Pacific Gyre (SPG) by analyzing 47 major, trace, and rare earth elements in bulk sediment in 206 samples from seven sites drilled during Integrated Ocean Drilling Program Expedition 329. We use multivariate statistical analyses (Q-mode factor analysis and multiple linear regression) of the geochemical data to construct a model of bulk pelagic clay composition and mass accumulation rates (MAR) of six end-members, (post-Archean average Australian shale, rhyolite, basalt, Fe-Mn-oxyhydroxides, apatite, and excess Si). Integrating the results with Co-based age models at Sites U1365, U1366, U1369, and U1370, we link changes in MAR of these components to global oceanographic, terrestrial, and climatic transformations through the Cenozoic. Our results track the spatial extent (thousands of kilometers) of dust deposition in the SPG during the aridification of Australia. Dispersed ash is a significant component of the pelagic clay, often comprising >50% by mass, and records episodes of Southern Hemisphere volcanism. Because both are transported by wind, the correlation of dust and ash MAR depends on the site's latitude and suggests meridional shifts in the position of atmospheric circulation cells. The hydrothermal MARs provide evidence for rapid deposition from the Osbourn Trough spreading ridge before it went extinct. Excess Si MARs show that the abrupt increase in siliceous productivity observed at Site U1371 also extended at least as far north as Sites U1369 and U1370, suggesting large-scale reorganizations of oceanic Si distributions ~10–8 Ma in the southern SPG
  • This is the publisher’s final pdf. The article is copyrighted by the American Geophysical UnionSociety and published by John Wiley & Sons, Inc. It can be found at: http://agupubs.onlinelibrary.wiley.com/agu/journal/10.1002/%28ISSN%291944-9186/
Resource Type
DOI
Date Available
Date Issued
Citation
  • Dunlea, A. G., Murray, R. W., Sauvage, J., Spivack, A. J., Harris, R. N., & D'Hondt, S. (2015). Dust, volcanic ash, and the evolution of the South Pacific Gyre through the Cenozoic. Paleoceanography, 30(8), 1078-1099. doi:10.1002/2015PA002829
Journal Title
Journal Volume
  • 30
Journal Issue/Number
  • 8
Dichiarazione dei diritti
Related Items
  • Supporting information:
Funding Statement (additional comments about funding)
  • Funding for this research was provided by the U.S. National Science Foundation to R.W.M. (NSF OCE1130531) as well as S.D. and A.J.S. (NSF OCE1130735).
Publisher
Peer Reviewed
Language
Replaces

Le relazioni

Parents:

This work has no parents.

Elementi

Thumbnail Titolo Data caricata Visibilità Azioni
file details HarrisRobertCEOASDustVolcanicAsh.pdf 2017-10-27 Pubblico Scaricare