摘要：

SUMMARYRock magnetic, palaeomagnetic and oxygen isotopic results are presented from core RNDB 75p, which was recovered from the Ontong-Java Plateau (OJP). A high degree of uniformity in magnetic properties characterized by relatively small changes in concentration and grain size in the upper 4 m of the core, combined with a lack of coherence between the normalized remanence and rock magnetic data suggests that the natural remanence normalized by saturation remanence reflects variations in relative palaeointensity of the geomagnetic field. The record from RNDB 75p replicates other Ontong-Java records spanning the last 400 Ka and extends the record back to some 700 Ka. Spectral analysis of the Ontong-Java record suggests periodic behaviour in the relative palaeointensity record with a dominant period of between 30 and 40 Ka, which appears not be be an artefact of lithologic variability. This dominant period lies between functions describing climatic precession and obliquity changes in th

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