Tristan da Cunha is the most remote inhabited island in the world. It takes 6 days to reach the island by ship, and vessels only visit 9 times a year. The main island is an active volcano that has in the past put the 264 inhabitants of the island in danger. Geologically, Tristan is important as a potential hotspot location for the plume that we think formed the Walvis Ridge.

The Tristan da Cunha island group is composed of 3 islands and 2 islets.
New ages for Tristan da Cunha show that the group is much younger than previously thought. Until now Middle Island was considered 12-18 million years old.

To understand Tristan's role in the formation of the Walvis Ridge, we need accurate ages for the island group. However, reliable ages are only available for the main island of Tristan. I have age-dated 24 rocks from Inaccessible, Nightingale and Middle in order to determine how long the island group has been active, and have found that the previously-held 18 myr maximum age is wrong. The new ages confirm that Tristan doesn't fit into the age progression formed by nearby seamounts. It is therefore not a zero-age end point for the Walvis Ridge chain, as was long assumed.