MIT Libraries logoDSpace@MIT

MIT
View Item 
  • DSpace@MIT Home
  • MIT Open Access Articles
  • MIT Open Access Articles
  • View Item
  • DSpace@MIT Home
  • MIT Open Access Articles
  • MIT Open Access Articles
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Impact of anthropogenic Pb and ocean circulation on the recent distribution of Pb isotopes in the Indian Ocean

Author(s)
Gamo, Toshitaka; Obata, Hajime; Norisuye, Kazuhiro; Echegoyen, Yolanda; Lee, Jong-Mi; Boyle, Edward A; ... Show more Show less
Thumbnail
DownloadImpact of anthropogenic.pdf (1.613Mb)
PUBLISHER_CC

Publisher with Creative Commons License

Creative Commons Attribution

Terms of use
Creative Commons Attribution-NonCommercial-NoDerivs License http://creativecommons.org/licenses/by-nc-nd/4.0/
Metadata
Show full item record
Abstract
b and Pb isotope ratios in the modern ocean have been altered significantly by anthropogenic Pb inputs over the past century. Most studies of anthropogenic Pb in the ocean have focused on the North Atlantic and North Pacific Oceans, and the impact of anthropogenic Pb inputs to the Indian Ocean and processes controlling the distribution of Pb in the Indian Ocean are poorly known. This study presents the Pb and Pb isotopic composition (²⁰⁶Pb/²⁰⁷Pb, ²⁰⁸Pb/²⁰⁷Pb) of 11 deep stations from the Indian Ocean Japanese GEOTRACES cruise (KH-09-5), from the Bay of Bengal and Arabian Sea to the Southern Ocean (62°S). The Pb isotope ratios of the Indian Ocean range 1.140–1.190 for ²⁰⁶Pb/²⁰⁷Pb and 2.417–2.468 for ²⁰⁸Pb/²⁰⁷Pb, with lower ratios appearing in the shallow waters of the northern Indian Ocean and higher ratios appearing in the deep layers of the Southern Ocean. This result agrees with a previous study on Pb concentrations (Echegoyen et al., 2014) showing that the Indian Ocean, particularly its northern part, is largely perturbed by anthropogenic Pb inputs. ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁷Pb of the Indian sector Southern Ocean are still lower than natural Pb, showing this region was also affected by anthropogenic Pb. Anomalously low or high ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁷Pb were observed in the thermocline and shallow waters of the southern Indian Ocean and the Arabian Sea, which are ascribed to water mass distribution (e.g., Subantarctic Mode Water) and evolving Pb isotope ratios of this region as dominant anthropogenic Pb sources change. ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁷Pb in the Bay of Bengal are higher than those in the Arabian Sea, which might be the result of the anthropogenic Pb inputs from different provenance or seawater exchanging Pb isotopes with natural particles derived from rivers and/or sediments at the basin boundaries.
Date issued
2015-08
URI
http://hdl.handle.net/1721.1/112337
Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Journal
Geochimica et Cosmochimica Acta
Publisher
Elsevier
Citation
Lee, Jong-Mi et al. “Impact of Anthropogenic Pb and Ocean Circulation on the Recent Distribution of Pb Isotopes in the Indian Ocean.” Geochimica et Cosmochimica Acta 170 (December 2015): 126–144 © 2015 Elsevier Ltd
Version: Author's final manuscript
ISSN
0016-7037

Collections
  • MIT Open Access Articles

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

Login

Statistics

OA StatisticsStatistics by CountryStatistics by Department
MIT Libraries
PrivacyPermissionsAccessibilityContact us
MIT
Content created by the MIT Libraries, CC BY-NC unless otherwise noted. Notify us about copyright concerns.