Figure F4. Plot of latitudinal distance from the 43-Ma bend in the Hawaiian-Emperor hotspot track vs. age (light circles). Age data are not available for Meiji, Tenchi, and Jimmu Seamounts; their positions, based on a constant latitudinal progression, are shown for reference. Dark circles indicate positions after the difference between the present-day latitude of the 43-Ma bend and Hawaii is subtracted from each of the present-day latitudes of the Emperor Seamounts. In effect, we slide the Emperor trend down the Hawaiian chain so that the bend coincides with the position of Hawaii (inset). This reconstruction allows the following test. If the Emperor Seamounts record mainly motion of the Hawaiian hotspot, paleolatitudes should fall close to this corrected latitudinal trend; if the hotspot has been stationary, the paleolatitudes should fall close to the present-day latitude of Hawaii. Triangles = paleolatitudes of Suiko and Detroit Seamounts, with 95% confidence intervals. The null hypothesis that the paleolatitude result from the Suiko Seamount is drawn from the same population as the Detroit Seamount data can be rejected at the 95% confidence level using nonparametric tests (Kolmogorov-Smirnov). In the absence of a rotation of the entire Earth with respect to the spin axis, known as true polar wander (Tarduno and Cottrell, 1997; Cottrell and Tarduno, 2000b; Tarduno and Smirnov, 2001), the hotspot may have moved continuously southward at a rate of 30-50 mm/yr while the plate also drifted slowly northward (shaded area). This figure is after Tarduno and Cottrell (1997).
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