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Data report: paleomagnetic measurements of igneous rocks from Shatsky Rise Expedition 3241

Margaret Pueringer,2 William Sager,2,3 and Bernard Housen4


Five sites were cored on Shatsky Rise, an oceanic plateau, during Integrated Ocean Drilling Program Expedition 324 to gain a better understanding of its formation processes. To augment and improve the shipboard paleomagnetic results, an additional 135 samples from Sites U1346–U1348 and U1350 were measured at the Northwest Paleomagnetism Laboratory at Western Washington University (USA). Samples from all sites were demagnetized using either alternating field (AF) or thermal demagnetization in approximately equal numbers. Most samples display a downward-directed overprint likely caused by the drill string magnetic field. This overprint was typically removed by ~10–15 mT AF demagnetization or ~300°C thermal demagnetization. AF demagnetization generally worked well to isolate a characteristic remanence direction, with samples mostly showing low (<10 mT) to moderate (10–20 mT) median destructive field values. Thermal demagnetization was also mostly successful in isolating a characteristic remanence at temperatures >350°–400°C. Some samples showed small sections of self-reversal during thermal demagnetization. Changes in inclination over depth showed little variation at Sites U1346 and U1347, but more variation was recorded at Site U1350. Hysteresis analysis showed that samples from all sites reside in the single-domain to pseudosingle domain region of the Day plot.

1 Pueringer, M., Sager, W., and Housen, B., 2013. Data report: paleomagnetic measurements of igneous rocks from Shatsky Rise Expedition 324. In Sager, W.W., Sano, T., Geldmacher, J., and the Expedition 324 Scientists, Proc. IODP, 324: Tokyo (Integrated Ocean Drilling Program Management International, Inc.). doi:10.2204/iodp.proc.324.202.2013

2 Department of Geology and Geophysics, Texas A&M University, College Station TX 77843, USA.

3 Current address: Department of Earth and Atmospheric Sciences, University of Houston, Houston TX 77204, USA.

4 Department of Geology, Western Washington University, Bellingham WA 98225, USA.

Initial receipt: 1 August 2012
Acceptance: 22 April 2013
Publication: 19 August 2013
MS 324-202