Nd, Sr and Pb isotopic composition of eolian dust deposited in the central North Pacific ...

• Main Authors: Pettke, Thomas, Halliday, Alex N, Hall, Chris M, Rea, David K
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2000
• Subjects: Drilling/drill rig; Leg145; Joides Resolution; Ocean Drilling Program ODP; Kamchatka
• Online Access: https://dx.doi.org/10.1594/pangaea.711212; https://doi.pangaea.de/10.1594/PANGAEA.711212

The silicate fractions of recent pelagic sediments in the central north Pacific Ocean are dominated by eolian dust derived from central Asia. An 11 Myr sedimentary record at ODP Sites 885/886 at 44.7°N, 168.3°W allows the evaluation of how such dust and its sources have changed in response to late Cenozoic climate and tectonics. The extracted eolian fraction contains variable amounts (>70%) of clay minerals with subordinate quartz and plagioclase. Uniform Nd isotopic compositions (epsilon-Nd =38.6 to 310.5) and Sm/Nd ratios (0.170-0.192) for most of the 11 Myr record demonstrate a well-mixed provenance in the basins north of the Tibetan Plateau and the Gobi Desert that was a source of dust long before the oldest preserved Asian loess formed. epsilon-Nd values of up to 36.5 for samples 62.9 Ma indicate <=35 wt% admixture of a young, Kamchatka-like volcanic arc component. The coherence of Pb and Nd in the erosional cycle allows us to constrain the Pb isotopic composition of Asian loess devoid of ... : Supplement to: Pettke, Thomas; Halliday, Alex N; Hall, Chris M; Rea, David K (2000): Dust production and deposition in Asia and the north Pacific Ocean over the past 12 Myr. Earth and Planetary Science Letters, 178(3-4), 397-413 ...