THE PSEUDO-THELLIER PALEOINTENSITY METHOD: NEW CALIBRATION AND UNCERTAINTY ESTIMATES
We explore a number of rock magnetic parameters to try and identify selection thresholds for reducing the calibration scatter, but fail to find a suitable choice. We infer that our careful paleointensity selection process may be largely screening out any strong rock magnetic dependence.
As a consequence of the variability in the calibration factor, the uncertainty associated with pseudo-Thellier results is much larger than previously indicated. The scatter of the calibration is ~25% of the mean value, which implies that, when combined with the scatter of results typically obtained from a single site, the uncertainty of averaged pseudo-Thellier results will always be >25%. As such, pseudo-Thellier results should be complementary to, and cross-validated with results from other methods. Nevertheless, the pseudo-Thellier method remains a valuable tool for obtaining paleointensity estimates from thermally sensitive geological, archeological, and extraterrestrial materials and with careful data selection and analysis can yield results that are accurate to within a factor of 4 or better.