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The magnetostratigraphy of Sites 747, 749, and 751 of Leg 120 that was established by shipboard measurements was extended and confirmed. Five hundred and eighty sediment cubes were stepwise demagnetized with alternating fields to determine their characteristic remanence. We obtained a rather complete magnetostratigraphy from the Oligocene to the Pliocene for the nannofossil oozes of Site 747. Alternating-field demagnetization experiments on laboratory-induced magnetization, hysteresis measurements, and low-temperature experiments showed that the magnetic carriers are single-domain and small pseudo-single-domain (titano)magnetite particles. A fraction of these Fe-Ti oxides seems to reside as microlites in the vitric volcanic ash particles that were enriched in the magnetic separates. The natural remanent magnetizations seem to be of detrital origin with small Fe-Ti oxide grains in the volcanic glass particles as carriers of the stable paleomagnetic signal. INTRODUCTION The objective of Ocean Drilling Program (ODP) Leg 120 was to investigate the origin and tectonic history of the Kerguelen Plateau in the South Indian Ocean. The magnetostratigraphy of the cored sediments was determined so that we could accurately date the biostratigraphic events. One aim of our study was to contribute to a combined magnetobiostratigraphy in high southern latitudes (Harwood et al., this volume; Berggren et al., this volume). In this paper we present results obtained from the single sediment samples of Sites 747, 749, and 751. The results from Sites 748 and 750 are described elsewhere (Inokuchi et al., this volume). The cores described here were recovered with the advanced hydraulic piston corer (APC) and the extended core barrel (XCB). The best paleomagnetic results were obtained on the generally well-preserved APC cores, as was previously found by Sager (1988). During Leg 120 a preliminary magnetostratigraphy was determined with the cryogenic magnetometer on the JOIDES Resolution using split 1.5-m-long sections of the core. The shipboard magnetometer worked extremely well, compared with previous legs, and a record of declination, inclination, and intensity of magnetization was obtained from all undisturbed cores. Nevertheless, the maximum alternating field (AF) that was available for demagnetization of the cores during the cruise was 9 mT. We had previously noticed that the magnetostratigraphic record became more similar to the standard polarity reversal sequence following removal of a normal overprint with the available 9-mT AF treatment (Schlich, Wise, et al., 1989). The question remained whether the 9-mT AF demagnetization was sufficient to isolate the characteristic inclinations, especially since some inclinations measured on board the ship were much shallower than the 72° expected for the high-latitude location. 1 Wise, S. W., Jr., Schlich, R., 1992. Proc. ODP, Sci. Results, 120: College Station, TX (Ocean Drilling Program). Geophysics Laboratory, Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada. 3 Institut für Allgemeine und Angewandte Geophysik, Ludwig-MaximiliansUniversitàt, Theresienstrasse 41, 8 München 2, Federal Republic of Germany. 4 Department of Earth Sciences, Faculty of Science, Kobe University, Kobe 657, Japan. The aim of the land-based measurements was to test the validity of the preliminary magnetostratigraphy from the ship and to fill in gaps that still existed in our record. Rock magnetic measurements were done on the sediments to characterize the magnetic remanence carriers. Biogenic singledomain (SD) magnetite has been found as the carrier of magnetization in detritus-poor pelagic sediments (Petersen et al., 1986). The sediments used for the magnetostratigraphy were mainly of pelagic origin and consisted of nannofossil, foraminiferal, and diatom ooze. Mainly carbonate-rich sediments were encountered because all sites were in 2100-m water depth well above the calcium carbonate compensation depth (CCD). Rock magnetic investigations were conducted to determine the magnetic domain state of the samples. In addition to biogenic SD magnetite, we investigated the role of vitric volcanic ash particles as carriers of stable magnetization. We follow the nomenclature for detrital remanent magnetizations (DRM) suggested in the review on sedimentary magnetism by Verosub (1977). A depositional DRM is a magnetization acquired by magnetic grains in the Earth's field while settling in water and on first contact with the sediment. A postdepositional DRM is formed after deposition when the magnetic particles are surrounded by sediment. METHODS Samples were taken with standard ODP cubes (7 cm) during the cruise. On average we obtained two samples per 1.5-m section of the core, when the sediment was not disturbed. Cubes were pressed into the sampling half of the core with the arrow on the plastic cube pointing in the upcore direction. The harder sediments were precut with a sharp stainless steel spatula before sampling with a plastic cube. The paleomagnetic measurements were carried out in the Paleomagnetism Laboratory of the Universitàt München with a two-axis cryogenic magnetometer. Magnetizations as weak as 3 10~ A/m could be measured on the single samples with this magnetometer. All samples were stepwise AF-demagnetized in three directions. Approximately 580 samples from Holes 747A-747C, 749B, and 751A were AF-demagnetized in at least five steps up to 60 mT in order to isolate their characteristic remanence components. The declinations of the single samples have no meaning because the cores were not oriented with respect to azimuth.

High Southern Latitude Magnetostratigraphy and Rock Magnetic Properties of Sediments from Sites 747, 749, and 751