Trust but verify: How to assess the reliability of paleomagnetic directions by using the R package PmagDirs

Abstract

Abstract Paleomagnetism is the most important source of information for determining the position of tectonic plates in the geological past. During the last decades significant advancement have been done for improving the reliability of paleomagnetic data, ranging from analytical methods to statistic assessment. Here I present the first version of PmagDirs, a R-based open-source package optimized for R-Studio that allows to display, assess the reliability, and, when possible, un-flaw a given paleomagnetic directions distribution. The main functions in the package are: plotting paleomagnetic directions distributions and their average, apply different direction cut-off to eliminate outliers, perform test for antipodality, comparing the distribution shape with the one predicted by a widely accepted paleosecular variation model, correcting flawed distributions for paleomagnetic inclination flattening, and correct for strain-derived paleomagnetic directions deviation when the strain fabric is known. Ultimately, directions can be converted in virtual geomagnetic poles and plot on spherical projection for comparison with reference apparent polar wander path. All main functions of the PmagDirs package return text results as comma separated value files as well as vector graphic files (pdf) optimized for publication purpose with minimal to none manipulation.