True Polar Wander: Linking Deep and Shallow Geodynamics to Hydro- and Biospheric Hypotheses

Abstract

Inertial adjustment of the solid Earth relative to its core and spin/magnetic-field axis is known as true polar wander (TPW), or sometimes ‘polar wandering.’ TPW interferes with plate motion derivations from apparent polar wander paths, but if the speed and magnitude of TPW is sufficiently fast and large (here labeled ‘type II’ TPW), global paleogeography may be reconstructed in a novel reference frame centered about the TPW axis. We outline such reconstruction using ‘spinner diagrams,’ and we demonstrate schematically that multiple, fast, type II TPW events hypothesized throughout Cryogenian–Ediacaran–Cambrian time may reconstruct the Paleozoic supercontinent Gondwanaland, completely independent of marine magnetic anomalies. This proof of concept strongly argues that fast TPW may be a frequent, as-yet unrecognized phenomenon at other times. We review the intervals of Earth history hypothesized to be marked by significant TPW, and we outline general oceanographic effects and carbon reservoir changes expected to be associated with fast TPW events.