Beschreibung: Integrated Ocean Drilling Program (IODP) Expedition 303 to the North Atlantic provided 16 records of the Matuyama-Brunhes polarity transition (MBT), based on u-channel and discrete samples, from holes drilled at three sites (Sites U1304, U1305 and U1306) that have mean Brunhes sedimentation rates of 16-18 cm/kyr. The MBT occurs during the transition from marine isotope stage (MIS) 19c to MIS 18e, with mid-point at ~773 ka, and a transition duration of ~8 kyr. Combining the new MBT records, including one new record for the top Jaramillo, with previously published North Atlantic MBT records (ODP Sites 983, 984 and 1063) yields a total of more than 20 high-sedimentation-rate polarity transition records. The MBT yields a repetitive pattern of transitional field states as virtual geomagnetic poles (VGPs) move from high southern latitudes to loop over the Pacific, group in NE Asia, and transit into the mid-latitude South Atlantic before reaching high latitudes in the Northern Hemisphere. The VGPs for the top Jaramillo transition feature a loop over the Pacific, then a NE Asia group before transit over the Indian Ocean to high southerly latitudes. The North Atlantic MBT records described here contrast with longitudinally-constrained VGP paths for the MBT, indicating that relatively low sedimentation rate (~4 cm/kyr) records of the MBT are heavily smoothed by the remanence acquisition process and do not adequately represent the MBT field. The VGPs at the MBT and top Jaramillo, as measured in the North Atlantic, have similarities with excursion (Iceland Basin) VGP paths, and were apparently guided by maxima in downward vertical flux similar to those seen in the modern non-dipole (ND) field, implying longevity in ND features through time.

Beschreibung: Here we present relative paleointensity (RPI) proxies for the 100-248 meters composite depth (1.3-3.2 Ma) interval from Integrated Ocean Drilling Program (IODP) Site U1308 (49° 53'N, 24° 14'W; water depth 3871 m). Methods are described in Channell et al. (2016) (Quaternary Science Reviews, 131, 1-19, 2016, doi:10.1016/j.quascirev.2015.10.011). The magnetic records for 0-1.3 Ma at Site U1308 were published in Channell et al. 2008 (Earth and Planetary Science Letters, 274, 59-71, 2008, doi:10.1016/j.epsl.2008.07.005) and have been archived at: https://doi.org/10.1594/PANGAEA.808942, https://doi.org/10.1594/PANGAEA.808945, https://doi.org/10.1594/PANGAEA.808946. Benthic oxygen isotope stratigraphy for the 0- 3.2 Ma interval are archived at (https://doi.org/10.1594/PANGAEA.871936) and are the basis for the age model. The mean sedimentation rate for the 1.3-3.2 Ma interval is 8.5 cm/kyr.