Theory and application of the Day plot ( M rs / M s versus H cr / H c ) 2. Application to data for rocks, sediments, and soils

New theoretical curves relating the hysteresis parameters M rs / M s and H cr / H c for single‐domain (SD), superparamagnetic (SP), pseudo‐single‐domain (PSD), and multidomain (MD) grains and their mixtures are applied to published data for natural materials. The Day plot of M rs / M s versus H cr / H c has been used to crudely classify samples into box‐like SD, PSD, and MD (or sometimes incorrectly, MD + SP) regions with arbitrary boundaries. New type curves for MD, PSD/SD + MD, and SD + SP grains and mixtures permit more subtle and precise modeling. The predicted MD trend and its junction with the PSD trend are observed in two data sets: for magnetite spherules from carbonate rocks and for…

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  Natural Sciences and Engineering Research Council of Canada