Paleospin axis locations since 48 Ma inferred from the distribution of equatorial sediment accumulation rates on the Pacific plate, together with paleomagnetic poles from magnetic anomaly skewness, indicate that the Hawaiian hot spot was nearly fixed in latitude from 48 to 12 Ma, but ≈3° north of its current latitude. From 48 to 12 Ma in the Pacific hot spot reference frame, which we take to be equivalent to the global hot spot reference frame, the spin axis was located near 87°N, 164°E, recording a stillstand in true polar wander. Global hot spots shifted coherently relative to the spin axis since ≈12 Ma, consistent with an episode of true polar wander, which may continue today. The motion of the spin axis away from the Hawaiian hot spot and toward Greenland since ≈12 Ma coincided with, and may have contributed to, the onset of northern hemisphere glaciation.

While it is well documented that the Hawaiian hot spot has shifted southward relative to the spin axis since the formation of some of the Emperor seamounts, the paleolatitude of the hot spot during the formation of the Hawaiian chain is poorly known. To better determine the latter, here we estimate the location of the 44 Ma Pacific plate paleomagnetic pole by investigating the skewness (asymmetry) of 14 airplane and 19 ship-board crossings of magnetic anomaly 20r between the Murray and Marquesas fracture zones on the Pacific plate. The new 44 Ma paleomagnetic pole (78.0°N, 26.0°E, A 95_1 = 5.4°at 101°, A 95_2 = 2.0°) differs by ≈4°from its position expected if the Pacific hot spots have been fixed relative to the spin axis. This shift is independently recorded by the chron 12r (32 Ma) Pacific plate skewness paleomagnetic pole and is also confirmed by paleomagnetic poles reconstructed from the continents, indicating that global hot spots have moved in unison with respect to the spin axis, probably due to true polar wander, which may continue today as recorded by optical astronomy and geodetic very long baseline interferometry. An analysis of spreading rates recorded in the magnetic profiles indicates that spreading rates doubled between ≈50 and ≈42 Ma (confirming prior results), as expected if the bend in the Hawaiian-Emperor chain records a change in Pacific plate motion relative to the deep mantle.

The motion of the Pacific plate relative to Pacific hotspots produces age‐progressive chains of volcanoes. Methods of analysis of volcano locations and age dates using a small number of adjustable parameters (10 per chain) are presented. Simple fits to age progressions along Pacific hotspot chains indicate 1σ dispersions of age dates of ≈±1.0–±3.0 Ma. Motion between the Hawaii and Louisville hotspots differs insignificantly from zero with rates of 2 ± 4 mm/a (=±2σ) for 0–48 Ma and 26 ± 34 mm/a (=±2σ) for 48–80 Ma. Relative to a mean Pacific hotspot reference frame, motions of the Hawaii, Louisville, and Rurutu hotspots are also insignificant. Therefore plumes underlying these Pacific hotspots may be more stable in a convecting mantle than previously inferred. We find no significant difference in age between the Eocene bends of the Pacific hotspot chains. The best‐fitting assumed‐coeval age for the bends is 47.4 ± 1.0 Ma (=±2σ), coincident with the initiation of the doubling of the spreading rate of the Pacific plate relative to the Farallon and Vancouver plates. The initiation of the Eocene collision of India with Eurasia preceded the formation of the bends and was completed after their formation. Initiation of subduction of the Pacific plate in the west and southwest Pacific Ocean Basin likely preceded the formation of the bends, consistent with subduction initiation changing the torque on the Pacific plate such that it started moving in a more westward direction thus creating the Hawaiian‐Emperor Bend.

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