Toward a generalized plate motion reference frame

An absolute plate motion (APM) model is required to address issues such as the thermochemical evolution of Earth’s mantle. All APM models have to rely on indirect inferences, including those based on hot spots and seismic anisotropy, each with their own set of uncertainties. Here, we explore a seafloor spreading-aligned reference frame. We show that this reference frame fits azimuthal seismic anisotropy in the uppermost mantle very well. The corresponding Euler pole is close to those of hot spot reference frames, ridge motion minimizing models, and geodynamic estimates of net rotation and predicts clear trench motion patterns. We conclude that a net rotation pole guided by the spreading-aligned model (at 64∘E, 61∘S, with moderate rotation of ∼ 0.2... 0.3∘/Myr) could indeed represent a standard, comprehensive reference frame for present-day plate motions with respect to the deep mantle.