Figure F112. Normalized magnetization decay curves of discrete samples from Holes 1270B (below) and 1270C and 1270D (above). Decay is plotted as a function of the vector difference sum, the cumulative sum of vector differences between demagnetization steps. The two slopes evident in samples from Hole 1270B are correlated with the presence of two distinct remanences, a partial low-field IRM induced during drilling, and a characteristic remanence that is stable over a higher range of coercivities. Steep slopes below 10 mT correspond to the presence of coarse-grained magnetite. In contrast, samples from Holes 1270C and 1270D yield uniform slopes over the whole coercivity range, indicating a more homogenous grain size distribution and less significant contribution from very low coercivity grains. B = the peak induction during demagnetization.

Figure F112. Normalized magnetization decay curves of discrete samples from Holes 1270B (below) and 1270C and 1270D (above). Decay is plotted as a function of the vector difference sum, the cumulative sum of vector differences between demagnetization steps. The two slopes evident in samples from Hole 1270B are correlated with the presence of two distinct remanences, a partial low-field IRM induced during drilling, and a characteristic remanence that is stable over a higher range of coercivities. Steep slopes below 10 mT correspond to the presence of coarse-grained magnetite. In contrast, samples from Holes 1270C and 1270D yield uniform slopes over the whole coercivity range, indicating a more homogenous grain size distribution and less significant contribution from very low coercivity grains. B = the peak induction during demagnetization.