The last two-geomagnetic polarity reversals recorded in high-deposition-rate sediment drifts

High-resolution records of geomagnetic polarity transitions are rare owing to the difficulty of preserving in the geological record details of a process with a duration of only a few thousand years. Lavas can record the instantaneous field on cooling, but lava records are themselves discontinuous and therefore polarity transition fields are seldom captured, Sedimentary records are more continuous, but typical deep-sea sedimentation rates of a few cm kyr(-1) are too low to record transition fields adequately. Here we report transition records from North Atlantic drift deposits with high sedimentation rates (similar to 12 cm kyr(-1)) at the Ocean Drilling Program sites 983 and 984. Virtual geomagnetic polar (VGP) paths are similar within and between sites for the last two geomagnetic reversals, attesting to a memory effect spanning back-to-back reversals, The complex VGP paths feature two VGP clusters (one located in northeastern Asia and the other in the South Atlantic Ocean off South America), and provide a link between the longitudinally constrained transitional VGPs often recorded in sediments(1,2)-which represent highly smoothed renditions of transition fields-and the scattered transitional VGPs(3) and VGP clusters(4) observed in lava records.