SO233 WALVIS II: Temporal and Geochemical Evolution of the Walvis Ridge (South Atlantic)
ACRONYM
SO233 WALVIS II
Title
SO233 WALVIS II: Temporal and Geochemical Evolution of the Walvis Ridge (South Atlantic)
General information
The Walvis Ridge is a textbook example of a hotspot track connected to a continental flood basalt province and represents the Atlantic “type locality” for the enriched mantle one (EM-I) geochemical endmember of intraplate volcanic rocks. Despite its importance in the global hotspot reference frame, endmember geochemical composition and uncertainties in its formation and evolution, basement sampling of the Walvis Ridge remained poor, in particular along its easternmost 1500 km. R/V Sonne cruise SO233 recovered a detailed suite of igneous samples along the Walvis Ridge. Ar/Ar ages and a comprehensive geochemical data set (major and trace elements and Sr-Nd-Pb-Hf-O isotopes) of these samples should allow (1) to test for age progressive volcanism along the ridge, (2) to differentiate between classical hotspot and plate fracturing models for its formation, and (3) to constrain the origin and temporal and spatial evolution of melting conditions and source compositions (in particular for the EM-I endmember and for zonation of mantle plumes). Complementary studies include the geophysical cruise MSM17/1, 2 in 2010/2011, magnetotelluric studies to decipher form and structure of todays melt anomaly beneath Tristan Island (MSM20/2 in 2012), a petrological cruise by our U.S. partners (Koppers, Class and Sager) to map and sample the Guyot Province between the Walvis Ridge and Tristan and Gough Islands in 2012 and the IODP 669 Walvis Ridge proposal. The biology program of SO233 WALVIS II intends to describe the benthic diversity of deep-sea invertebrates of the Walvis Ridge and will help to identify proxies of species connectivity and dispersal between the Walvis Ridge and neighboring ridge like structures (i.e. MSM 19-3, Agulhas Ridge; MARID, Madagascar Ridge).
Start
January, 2014
End
June, 2016
Funding (total)
393000
Funding (GEOMAR)
393000
Funding body / Programme
-
BMBF
/ SONNE-Ausfahrt
Coordination
Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), Germany
Contact
Partners
Museum für Naturkunde Berlin (Germany)
University of Oregon, Corvallis (U.S.A.)
Lamont Earth Observatory (U.S.A.)
Texas A&M University (U.S.A.)
University of Oregon, Corvallis (U.S.A.)
Lamont Earth Observatory (U.S.A.)
Texas A&M University (U.S.A.)