Analysis of palaeomagnetic inclination data

Summary

The analysis of palaeomagnetic data where only inclinations are available is considered. Maximum likelihood estimates for the mean inclination I₀ and Fisher's precision parameter k are derived. It is shown that they are in all cases biased although the bias is small for low inclinations. The case of steep inclinations and small values of k is examined and it is shown that in this region I₀ and k are not separable as distinct variables, because the lack of declination information in this region leads to fundamental ambiguities. Unbiased estimates for I₀ and (1/k) are derived for the case where the portion of the distribution folded about the vertical is insubstantial. A worked example of the method, with calculation of confidence limits, is appended.

Author notes

⋆

Research School of Earth Sciences, Australian National University, PO Box 4, Canberra, ACT 2600, Australia.

†

Geology Department, Tsumeb Corporation, PO Box 40, Tsumeb 9000, South West Africa.