- AGU 2015 Abstract [LINK]
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.
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.