Earth rotation shifts occurred during dinosaur era, study finds

A study published in the journal Science suggests that Earth's surface may have shifted its position relative to its axis of rotation several times during the era of the dinosaurs. Led by scientist Mathew Domeier from the University of Oslo, the research identifies episodes of true polar wander (TPW) occurring during the Jurassic and Cretaceous periods.

This phenomenon describes a relative movement between the Earth's solid outer layers—the crust and mantle—and its axis of rotation, rather than a flip of the planet or a shift in magnetic poles. The researchers propose a new method for detecting these episodes by analyzing changes in sea-level distribution across continents. Because Earth is not a perfect sphere, mass redistribution caused by mantle convection or plate subduction can alter the planet's equilibrium and trigger reorientation relative to the axis.