Current plate velocities relative to the hotspots incorporating the NUVEL‐1 global plate motion model

Abstract

NUVEL‐1 is a new global model of current relative plate velocities [DeMets et al., 1990], which differ significantly from those of prior models. Here we incorporate NUVEL‐1 into HS2‐NUVEL1, a new global model of plate velocities relative to the hotspots. HS2‐NUVEL1 was determined from the hotspot data and errors used by Minster and Jordan [1978] to determine AM1‐2, which is their model of plate velocities relative to the hotspots. AM1‐2 is consistent with Minster and Jordan's relative plate velocity model RM2. Here we compare HS2‐NUVEL1 with AM1‐2 and examine how their differences relate to differences between NUVEL‐1 and RM2. HS2‐NUVEL1 plate velocities relative to the hotspots are mainly similar to those of AM1‐2. Minor differences between the two models include the following: (1) in HS2‐NUVEL1 the speed of the partly continental, apparently non‐subducting Indian plate is greater than that of the purely oceanic, subducting Nazca plate; (2) in places the direction of motion of the African, Antarctic, Arabian, Australian, Caribbean, Cocos, Eurasian, North American, and South American plates differs between models by more than 10°; (3) in places the speed of the Australian, Caribbean, Cocos, Indian, and Nazca plates differs between models by more than 8 mm/yr. Although 27 of the 30 RM2 Euler vectors differ with 95% confidence from those of NUVEL‐1, only the AM1‐2 Arabia‐hotspot and India‐hotspot Euler vectors differ with 95% confidence from those of HS2‐NUVEL1. Thus, substituting NUVEL‐1 for RM2 in the inversion for plate velocities relative to the hotspots changes few Euler vectors significantly, presumably because the uncertainty in the velocity of a plate relative to the hotspots is much greater than the uncertainty in its velocity relative to other plates.