A rapid multiple‐sample approach to the determination of absolute paleointensity

Abstract

We present an alternative approach to absolute paleointensity determination, one which involves exactly five heatings, making possible rapid determinations without compromise to matters that insure reliability. While the Thellier‐Thellier method involves a large number of temperature steps to validate a result for a particular specimen, the new approach makes use of the spatial variation in rock magnetic properties. The procedure involves the simultaneous thermal treatment of several subspecimens sampled from different regions throughout the igneous rock unit under investigation. For inclusion of data in a given determination, self‐consistency criteria must be satisfied at the level of individual subsamples as well as at the stage of whole sample core consideration. The use of data taken en masse on a single Arai plot associated with samples from throughout a rock unit eliminates the need for further confirmation of an apparently successful result. The new method takes a balanced approach toward addressing the question of self‐consistency, from intraspecimen to intersample, that we argue is preferable to the common practice of focusing attention primarily on the individual specimen with inadequate consideration paid to consistency throughout a rock unit.