True polar wander associated with continental drift on a hypothetical Earth
© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2007
Received: 23 May 2006
Accepted: 11 April 2007
Published: 27 June 2007
Long-term true polar wander of the Earth (TPW) has generally been discussed by taking into account con-vective processes in the mantle such as downgoing slabs and upwelling plumes. Here I examined a relationship between continental drift and TPW on a hypothetical Earth with no such convective processes in the mantle. I evaluated temporal changes in moments of inertia owing to continental drift during a period of ~250 Ma based on a paleogeographic reconstruction, in which I estimated the lateral density heterogeneities by factoring in the observed mean land elevation of continents and average age of the oceanic lithosphere. The predictions for a viscoelastic Earth model with plausible viscosity models indicate that the long-term TPW might have been affected by continental drift throughout Cenozoic and Mesozoic times, which has wholly proceeded by maintaining isostasy at a certain depth, as well as convective processes in the mantle.