Hawaiian-Emperor Volcanic Chain: The Great Bend

By: Sarah Flaskerud

Abstract

            The Great bend of the Hawaiian-Emperor chain, which is located at 30°N latitude and 170°W longitude, has brought up the debate regarding the Hawaiian hotspot and how it formed the Hawaiian-Emperor chain in the Pacific Ocean.  In 1963 Tuzo Wilson came up with the hotspot hypothesis. He noticed that the islands progressively got older in age as you moved up the chain to the NW. From this he explained that the Hawaiian-Emperor chain was formed by the Pacific Plate moving over a stationary hotspot in the Pacific Ocean.  He explained the bend as being a large change in the direction of the Pacific Plate.  However, there have been some new discoveries that tend to lead away from the hotspot hypothesis proving it wrong. One example is that there is no record in a large plate movement during the time of the bend. Another is that paleomagnetic samples taken from the Emperor seamounts state that they were formed at a higher latitude than where the hotspot is currently at now.  The Hawaiian hotspot is not fully explained by any current hypothesis and thus needs more research to be able to fully understand exactly what happened in the Pacific over the last 100 Ma.

Foulger, G.R.

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