N | FRAC | β | q | MADANC | α | DRAT | |K’|* |
|---|
≥ 4 | ≥ 0.35 | ≤ 0.1 | ≥ 4 | ≤ 10 | ≤ 15 | ≤ 10% | – |
- N is the number of data points on the Arai plot. FRAC is a measure of the amount of NRM used. The parameter β is a measure of the Arai plot data scatter, q is the quality factor, MADANC and α are measures of how well a specimen’s direction trends to the origin. DRAT checks for alteration by comparing the error to the length of the best-fit line, and |K’| measures the curvature of the selected portion of the Arai plot. Parameters were calculated according to the standard palaeointensity definitions (Paterson et al. 2014)
- *|K’| was not used as an explicit selection criterion but will rather be used as a measure of the technique’s efficacy. Additional file 1 contains the data suggested for use in any future SOH meta-analysis
