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At Site U1554, 3 APC holes were cored to approximately 70 mbsf and a 4^th shallow hole was drilled down to approximately 14 mbsf. Four MOTs, 3 Icefield MI-5s and 1 Flexit, were deployed for testing purposes while coring these holes. The MOTs consistently gave values expected for the site, with the exception that of one tool which gave values 180° off on average. The source of this error was fortunately discovered at the end of the expedition and once corrected, this tool also gave good results. This discovery may have larger implications for MOT data from previous expeditions that also have values that appeared to be 180° from anticipated values. Other, smaller sources of error affecting MTF angles were identified during the set up and the MOT and the core barrel on the rig floor. These errors could account for values which appear to differ by less than 180° from the expected value. Of the 25 cores recovered at site U1554, 24 provide an excellent, high-resolution record of Bruhnes age sediment including several geomagnetic excursions. Only one core was excluded due to significant coring disturbances.

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The paleomagnetic standards page table and user guide on confluence were both updated. When the standards were measured during expedition Exp378, declination and inclination appeared correct but the intensities that were measured were approximately an order of magnitude less than the listed intensity. During this expedition it was realized that the standard’s listed intensity was calculated using a volume of 1 cm³ not 7 cm³ as was assumed. When the measured intensity is calculated using 1 cm³, the measured intensity is in agreement with the listed intensity. The table which contains the standards values has been updated to have both values.

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