)
was measured. The saturation isothermal remanent magnetization (SIRM) was
induced in a 1-T direct field and stepwise AF demagnetized at 20, 25, and 30 mT.The measurements of
natural remanent magnetization and anhysteretic remanent magnetization (ARM) of
the u-channel samples were carried out at the University of California, Davis,
with a 2G pass-through cryogenic magnetometer in a shielded room. The u-channels
were measured at 1-cm intervals, but because of the response function of the
pick-up coils, only every fourth measurement is independent (Weeks et al.,
1993). The stepwise AF demagnetization of the NRM was carried out with steps of
5, 10, 15, 20, 25, 30, 40, and 50 mT. After demagnetizing the NRM, an ARM was
applied at 100-mT AF with a 0.05-mT bias field followed by stepwise
demagnetization at 20, 25, and 30 mT. In addition, the initial susceptibility ()
was measured. The saturation isothermal remanent magnetization (SIRM) was
induced in a 1-T direct field and stepwise AF demagnetized at 20, 25, and 30 mT.
The NRM, ARM, and isothermal remanent magnetization (IRM) of the discrete samples were measured with a 2G cryogenic magnetometer at the paleomagnetic laboratory of the Universität München. The NRM of all single samples was measured and stepwise AF demagnetized up to 40 or 50 mT. Some of the specimens had already been demagnetized on the ship to an AF step of 20 mT. Magnetic susceptibility was measured with a KLY 2 Kappabridge. The ARM was induced in the single samples at 150-mT AF with a 0.05-mT bias field and the SIRM with a 1-T direct field. Both remanences were demagnetized at 20-mT AF. The remanent coercive force (Bcr) and the hysteresis loops of 24 samples were measured with a variable field translation balance.
