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Marine Geophysical Researches

, Volume 30, Issue 3, pp 207–214 | Cite as

The SW African volcanic rifted margin and the initiation of the Walvis Ridge, South Atlantic

  • Gavin M. Elliott
  • Christian Berndt
  • Lindsay M. Parson
Original Research Paper

Abstract

The continental margin of SW Africa is typical of a volcanic rifted margin associated with a hotspot trail characterized by a large volcanic ridge, the Walvis Ridge, defining the hotspot migration, and extensive extrusive volcanism that produced seaward-dipping reflectors (SDR). Previously unpublished seismic data show two significant anomalies of the SW African Margin when compared to other typical volcanic rifted margins: (1) Hyaloclastitic outer highs are rare, and (2) the SDR in the North dip towards the Walvis Ridge. We explain these anomalies by a major transform segment close to the centre of volcanism combined with pulsed volcanism. The Walvis Ridge represents an east-west striking extrusive centre which produced a SDR sequence. Following break-up the northern boundary of the Walvis Ridge became a left lateral transform fault. Our data support the idea that a transform fault system interacting with a ridge jump were responsible for the accretion of the São Paulo Plateau to the American plate.

Keywords

Volcanic rifted margins Walvis Ridge Outer highs Seaward-dipping reflectors 

Notes

Acknowledgments

We thank Western Geco for making the seismic data available to this study. The quality of this work was improved significantly due to comments raised by two anonymous reviewers and by editor Peter Clift.

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Gavin M. Elliott
    • 1
    • 2
  • Christian Berndt
    • 1
    • 3
  • Lindsay M. Parson
    • 1
  1. 1.Geology & Geophysics NSRDNational Oceanography CentreSouthamptonUK
  2. 2.Department of Earth Science & EngineeringImperial CollegeLondonUK
  3. 3.IfM-Geomar, Leibniz Institute for Marine SciencesKielGermany

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