The magnetic record of sediments from Sites 1138 and 1140 determined on board with the pass-through cryogenic magnetometer was confirmed, in general, by our land-based stepwise AF demagnetization of discrete samples. However, the analysis of discrete samples showed that for some parts of Site 1138, the shipboard demagnetization of 20 mT was not sufficient to obtain the characteristic direction of the magnetization, and the preliminary polarities had to be reviewed.
The rock magnetic investigation showed that titanomagnetites with varying Ti content are the main magnetic minerals in the sediments from Sites 1138 and 1140. IRM acquisition, hysteresis analyses, and thermomagnetic analyses have been conducted. The magnetic domain state for most of the investigated samples was determined as PSD.