Fig. 1. The ODP core orientation convention. The double line on the core liner of the working half of the core is the fiducial line that is oriented by the downhole magnetometer and by which orientation is maintained during core processing. It is the +X direction in core measurements.

Fig. 2. Schematic diagram of the deformation of sediments inside and outside of the penetrating core barrel of the advanced piston corer (APC) (from Acton et al., 2002).

Fig. 3. Test of effect of deformation of sediments on magnetization in the field of core barrels. The three panels show the intensity of NRM, the extent of individual cores and sections, and the intensity after demagnetization to 20 mT of Leg 174B Hole 1074A Core 6H. Note that the intensity is decreased by an order of magnitude by demagnetization and that the strong anomaly at approximately 51 mbsf is present both before and after demagnetization.

Fig. 4. Test of effect on magnetization of sediments of passage through BHA and up drill string during recovery. Note that the anomaly at approximately 105 cms in section is seen before and after demagnetization, but that it is at the level of the background signal level after demagnetization.

Fig. 5. Test of effect of magnetic field from bottom hole assembly (BHA). (a) Holes 1170A and 1171B showing difference in NRM intensity records of cores recovered with different drill bits in the BHA and (b) investigation of possible role of magnetic contamination by comparison of NRM intensity with susceptibility. The middle panel shows cores and sections to aid in recognition of core end effects. Note the susceptibility peaks are predominantly at core tops and reflect contamination.

Fig. 6. Effect of storage test: when Section 1173A-1H-1 was stored overnight a predominantly positive change in magnetization was observed in X corresponding to the ambient field.

Fig. 7. Effect of core splitting on X component of magnetization. Top panel: Comparison between initial X component of whole core after demagnetization to 20 mT (open square) with X component of core after splitting, but measured as whole round (filled square). Middle panel: Comparison between X component when measured as whole core (filled square) and when archive half (AH) is separated (open circle). Bottom panel: Comparison between X component of AH (open circle) and when demagnetized to 20 mT (filled circle).

Fig. 8. Effect of core splitting on directions of magnetization: (a) whole core demagnetized to 20 mT, (b) whole core split, but measured as whole core, (c) archive half (AH) separated before measurement, and (d) AH demagnetized to 20 mT.

Fig. 9. Leg 182 site map in Great Australian Bight (Feary et al., 2000).

Fig. 10. Magnetostratigraphy of Leg 182 sediments demonstrating the presence of a thick wedge of Brunhes Chron sediments in the Great Australian Bight. Black—normal polarity, unfilled—reversed polarity. Hachured—older section.

Fig. 11. 

Fig. 12. Example of attempts at high-resolution magnetostratigraphy using (a) Leg182-1130A-11H-5 to Leg182-1130A-18H-cc and Leg182-1130B-12H-2 to Leg182-1130B-19x-3 comparison between NRM intensity and standard intensity records (SINT; Guyodo and Valet, 1999) and (b) susceptibility and del ¹⁸O records for 1131A-1H-1 to 1131A-7H-6.

Fig. 13. Leg 189 site map around Tasmania (Exon et al., 2001).

Fig. 14. Magnetostratigraphy of Pleistocene and late Pliocene sediments from Hole 1172B of Leg 189 showing an hiatus that included part of the Matuyama Chron (C1r) and the whole Jaramillo sub-chron (C1r.1n).

Fig. 15. Correlation of low field magnetic susceptibility records from Holes 1172A and 1172D using peaks associated with input of volcaniclastics.

Fig. 16. Magnetostratigraphy with interpretation aided by susceptibility correlation and paleontology, which can be used for timing of deepening of Tasmanian Gateway at 35.5 Ma in C16n.1n.

Fig. 17. Site map of Queensland and Marion Plateaus—enclosed area labeled Fig. 2 covers the Leg 194 sites (Isern et al., 2002).

Fig. 18. Seismic definition of sequence boundary R and its use in calculating the late middle Miocene sea level fall (Isern et al., 2002).

Fig. 19. Magnetostratigraphic definition of age of sediments immediately above the R sequence boundary on the platform (left hand panel) and the age of the BC megasequence boundary from 1195 (right hand panel).

Fig. 20. Summary of temperature change during Cenozoic illustrating the settings of Leg 189 investigations of the onset of glaciation in Antarctica associated with the opening of the Tasman Gateway and the build up of the circum-Antarctic current (35.5 Ma) and of Leg 194 investigations of the build up of Antarctic Ice reflected in the late middle Miocene sea level fall (12.5–11.4 Ma) (Exon et al., 2001).