Based on the history of Mesozoic–Cenozoic plate motions, as well as simple dynamical considerations, a “speed limit” for tectonic plates has been suggested at ∼20 cm/yr. Previous paleomagnetic data from the Early Cambrian of Gondwana are conflicting but generally imply rapid motions approaching that limit. Herein we describe results from a continuous paleomagnetic sampling of Lower to Middle Cambrian strata from the Amadeus Basin, central Australia. We find characteristic remanence directions that show an ∼60° declination shift through the section. Assuming a tectonically assembled Gondwana supercontinent by Early Cambrian time, this large vertical-axis rotation of its Australian sector corresponds to an equally large translation across paleolatitudes for its Brazilian and West African sectors. Analysis of all high-quality paleomagnetic data from Gondwana both confirms and constrains the 60° rotation to have occurred toward the end of Early Cambrian time, at rates exceeding 16 +12/–8 cm/yr. These observations suggest that either nonuniformitarian plate tectonics or an episode of rapid true polar wander occurred during the Cambrian “explosion” of animal life.

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