WALVIS RIDGE

The Walvis Ridge is a 3000 km long volcanic feature in the South Atlantic, stretching from the coast of Namibia to the islands of Tristan da Cunha. The trail is 130 million years old at its origin in Namibia and there is a clear age progression towards very recent volcanism at Tristan da Cunha. This age progression and the presence of a large igneous province at its old end has led scientists to hypothesize a hotspot origin for the Walvis Ridge.

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An overview map of the Walvis Ridge and surrounding region.

For my PhD I am using 40Ar/39Ar geochronology to date rocks dredged from seamounts in the young Walvis Ridge guyot province. The young end of the Walvis Ridge is very complex, with many small seamounts and guyots spread out over a large area. It's hard to tell which of these seamounts were formed by hotspot volcanism and which might be related to Mid-Atlantic Ridge processes.

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Ishmael Guyot, in the young Walvis Ridge guyot province. The difference in resolution between satellite altimetry and shipboard multibeam sonar is very clear.