Another Simple Test for the Presence of Multidomain Behavior During Paleointensity Experiments

Abstract

Paleointensity measurements are vital for understanding the deep Earth and the evolution of the geomagnetic field, however, they suffer from non-ideal behavior that compromises the fidelity of the results. In an attempt to screen for non-ideal behavior in paleointensity experiments, selection criteria are used. One such non-ideal behavior is partial thermoremanent magnetization tails, which in the IZZI protocol result in a zig-zagging pattern on an Arai plot. While checks for these tails can be performed, these are not routinely used in experiments. We set out a new framework with which to create, develop, and re-assess selection criteria before applying it to our proposed new selection statistic, Ziggie, which is specific to detecting zig-zagging behavior. In creating Ziggie, we have attempted to define a criterion that is able to objectively and robustly identify the target behavior, consistently provide a quantifiable assessment of the target behavior, and is predominately sensitive to the target behavior while being free of undue influences. Other pre-existing statistics identifying Arai plot zig-zag, Z*, IZZI_MD, β, and SCAT, are also tested, but fail to meet all requirements. When a criterion of Ziggie ≤ 0.1 is applied to real IZZI data we find an overall improvement in the results and suggest the adoption of this criterion in future IZZI analysis.