On Detecting Changes in the Earth's Radius

Abstract

Estimates of the Earth's radius in the geological past can be made from paleomagnetic evidence. A method appropriate to the spherical environment of the data for dealing with this problem is given, which is applied to Devonian, Permian and Triassic data from Europe and Siberia, yielding estimated radii for these periods of 1.12, 0.94 and 0.99 times the present radius respectively. These estimates are not considered to be significantly different from the present radius.