RELATIVE GEOMAGNETIC FIELD INTENSITY AND REVERSALS FOR THE LAST 1.8 MY FROM A CENTRAL EQUATORIAL PACIFIC CORE

摘要

We have made a new analysis of core KK78O30 from the central equatorial Pacific. This core has recorded the last 4 reversals. Mineral-magnetic analysis establishes that these sediments meet the current criteria for reliable relative paleointensity determinations. Normalisation with ARM, IRM and chi yields very similar results. There is no evidence for a ''saw-tooth'' pattern such as the one obtained by Valet and Meynadier [1993] and Meynadier et al. [1994] for the last 4 million years. Rather, the average field intensity record appears to display more or less symmetric peaks and troughs, superposed to a broad high between reversals. [References: 15]