Shallow bias in Neogene palaeomagnetic directions from the Guide Basin, NE Tibet, caused by inclination error

Abstract

SUMMARY Too-shallow inclinations have frequently been observed in Cenozoic sedimentary strata in central Asia, and new palaeomagnetic results obtained by us from the Guide Basin in NE Tibet are no exception. We use a statistical analysis technique developed by Tauxe and Kent (TK03.GAD), which is based on a geomagnetic field model that predicts distributions of palaeomagnetic directions, and show that the too-shallow Neogene mean inclination (44 °) from 627 sites can be corrected to a value of 58 °, which closely matches the inclination predicted for the area. We conclude that syn- to post-depositional flattening is the most likely cause for the widely observed inclination bias in central Asia.