<P> The oldest and most heavily eroded part of the chain are the Emperor seamounts, which are 39 to 85 million years in age . The Emperor and Hawaiian chains form an angle of about 120 ° . This bend was long attributed to a relatively sudden change of 60 ° in the direction of plate motion, but research conducted in 2003 suggests that it was the movement of the hotspot itself that caused the bend . The issue is still currently under debate . All of the volcanoes in this part of the chain have long since subsided below sea level, becoming seamounts and guyots (see also the seamount and guyot stages of Hawaiian volcanism). Many of the volcanoes are named after former emperors of Japan . The seamount chain extends to the West Pacific, and terminates at the Kuril--Kamchatka Trench, a subduction zone at the border of Russia . </P> <P> The oldest age for the Emperor Seamounts is 81 million years, and comes from Detroit Seamount . However, Meiji Guyot, located to the north of Detroit Seamount, is likely somewhat older . </P> <P> In 1963, geologist John Tuzo Wilson hypothesized the origins of the Hawaiian--Emperor seamount chain, explaining that they were created by a hotspot of volcanic activity that was essentially stationary as the Pacific tectonic plate drifted in a northwesterly direction, leaving a trail of increasingly eroded volcanic islands and seamounts in its wake . An otherwise inexplicable kink in the chain marks a shift in the movement of the Pacific plate some 47 million years ago, from a northward to a more northwesterly direction, and the kink has been presented in geology texts as an example of how a tectonic plate can shift direction comparatively suddenly . A look at the USGS map on the origin of the Hawaiian Islands clearly shows this "spearpoint". </P> <P> In a more recent study, Sharp and Clague (2006) interpret the bend as starting at about 50 million years ago . They also conclude that the bend formed from a "traditional" cause--a change in the direction of motion of the Pacific plate . </P>

In what direction was the pacific plate moving while the emperor seamounts were forming