Figure 1

Comparison of torques (i) required to change contemporary plate motions and (ii) provided by the coseismic stress release of large earthquakes. Each dot corresponds to one tectonic plate whose Euler vector is available in the global tectonic model of Kreemer et al.⁸, and shows the magnitude of the torque required in order to change the plate angular velocity (\(\omega\)) — and thus the plate’s motion — by one standard deviation (\(\sigma _{\omega }\)). Each plate angular velocity features its own standard deviation, which is calculated from the Euler-vector covariances provided by Kreemer et al.⁸. Dots are coloured according to the ratio \(\sigma _{\omega }/\omega\), which, to first-degree, is a proxy for the precision with which GNSS data constrain the motion of the plate at hand. At the lower end of the colour-scale are plates whose angular-velocity standard deviation is small relative to the angular velocity itself. Torque estimates are made assuming that the average viscosity of Earth’s asthenosphere is \((3 \pm 2) \times 10^{19}~\mathrm {Pa \cdot s}\) (uncertainty range is in thin black), and are plotted as a function of the plate area (horizontal axis). Black ticks on the horizontal axis indicate the areas of Anatolia, Nazca, South America and Pacific, for reference. Black ticks on the vertical axis report the magnitudes of the torque associated with the coseismic stress release of four recent, large earthquakes.