A relative geomagnetic paleointensity stack from Ontong-Java']Java Plateau sediments for the Matuyama

We present a stack of geomagnetic paleointensity estimates for the Matuyama Chron (0.778-2.582 Ma). Sedimentary magnetizations from 4 Ocean Drilling Program (ODP) cores from the Ontong-Java Plateau (OJP) are analyzed with thermal techniques. Thellier-Thellier experiments are used to determine magnetic properties and indicate that a thermal treatment to 250 degrees C can be used for paleointensity estimates. The correlated records form a coherent OJP stack, which is dated at reversal boundaries. A coherent feature with two other data sets spanning the Matuyama Chron is the occurrence of a 150-kyr cyclicity. However, the time control of the OJP stack is not accurate, except for the 10 tie points at the reversals. This could, at least in part, explain why the three Matuyama paleointensity records show no other coherent frequencies.