Vailulu'u undersea volcano: The New Samoa Public Deposited

http://ir.library.oregonstate.edu/concern/defaults/n870zs38f

Copyright 2000 by the American Geophysical Union

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • Vailulu'u Seamount is identified as an active volcano marking the current location of the Samoan hotspot. This seamount is located 45 km east of Ta'u Island, Samoa, at 169°03.5′W, 14°12.9′S. Vailulu'u defines the easternmost edge of the Samoan Swell, rising from the 5000‐m ocean floor to a summit depth of 590 m and marked by a 400‐m‐deep and 2‐km‐wide summit crater. Its broad western rift and stellate morphology brand it as a juvenile progeny of Ta'u. Seven dredges, ranging from the summit to the SE Rift zone at 4200 m, recovered only alkali basalts and picrites. Isotopically, the volcano is strongly EM2 in character and clearly of Samoan pedigree (⁸⁷Sr/⁸⁶Sr: 0.7052–0.7067; ¹⁴³Nd/¹⁴⁴Nd: 0.51267–0.51277; ²⁰⁶Pb/²⁰⁴Pb: 19.19–19.40). The ²¹⁰Po‐²¹⁴Pb data on two summit basalts indicate ages younger than 50 years; all of the recovered rocks are extremely fresh and veneered with glass. An earthquake swarm in early 1995 may attest to a recent eruption cycle. A detailed nephelometry survey of the water column shows clear evidence for hydrothermal plume activity in the summit crater. The water inside the crater is very turbid (nephelometric turbidity unit (NTU) values up to 1.4), and a halo of “smog” several hundred meters thick encircles and extends away from the summit for at least 7 km. The turbid waters are highly enriched in manganese (up to 7.3 nmol/kg), providing further evidence of hydrothermal activity. Vailulu'u is similar to Loihi (Hawaii) in being an active volcanic construct at the eastern end of a hotspot chain; it differs importantly from the Hawaiian model in its total lack of tholeiitic basalt compositions.
Resource Type
DOI
Date Available
Date Issued
Citation
  • S.R. Hart, H. Staudigel, A.A.P. Koppers, J. Blusztajn, E. T. Baker, R. Workman, M. Jackson, E. Hauri, M. Kurz, K. Sims, D. Fornari, A. Saal and S. Lyons, 2000, Vailulu'u Undersea Volcano: The New Samoa. Geochemistry, Geophysics, Geosystems, Vol 1.
Series
Keyword
Rights Statement
Publisher
Language
Replaces
Additional Information
  • description.provenance : Submitted by David Moynihan (dmscanner@gmail.com) on 2010-04-19T19:52:58Z No. of bitstreams: 1 Hart et al GGG 2000.pdf: 676040 bytes, checksum: 7a26934165312757fe77138076923852 (MD5)
  • description.provenance : Approved for entry into archive by Linda Kathman(linda.kathman@oregonstate.edu) on 2010-04-20T13:44:41Z (GMT) No. of bitstreams: 1 Hart et al GGG 2000.pdf: 676040 bytes, checksum: 7a26934165312757fe77138076923852 (MD5)
  • description.provenance : Made available in DSpace on 2010-04-20T13:44:41Z (GMT). No. of bitstreams: 1 Hart et al GGG 2000.pdf: 676040 bytes, checksum: 7a26934165312757fe77138076923852 (MD5) Previous issue date: 2000-12-08
ISSN
  • 1525-2027

Relationships

In Administrative Set:
Last modified: 07/21/2017

Downloadable Content

Download PDF
Citations:

EndNote | Zotero | Mendeley

Items