During DSDP Leg 65, we achieved significant basement penetration at three sites (482, 483, and 485) in the mouth of the Gulf of California (Lewis and Robinson, 1983, doi:10.2973/dsdp.proc.65.1983). Since these holes were all drilled into extremely young crust near the crest of the East Pacific Rise, the rocks we recovered present an unusual opportunity to study the magnetic properties of submarine basalts before alteration has become pervasive. To take advantage of this opportunity and to complement the paleomagnetic studies conducted on these basalts by Day (1983, doi:10.2973/dsdp.proc.65.138.1983), we have studied, in the same samples, the following properties: saturation magnetization (Js); intensity and stability of isothermal remanent magnetization (IRM); hysteresis parameters, such as the coercive force (Hc), the remanent coercive force (HRC), and the ratio of saturation remanence (JRS) to saturation magnetization; susceptibility (x); and Curie temperature (Tc). In this chapter we will discuss the results of these studies in conjunction with the opaque mineralogy of the samples.

Sediment depth is given in mbsf. Stable Inclination: Sample 65-482C-15-4,68 = 14-18; sample 65-482D-10-2,111 = 40-42.

Supplement to: Day, Ron; Osterhoudt, Mary; Bleil, Ulrich (1983): Rock magnetism of igneous rocks from Deep Sea Drilling Project Sites 482, 483, and 485. In: Lewis, BTR; Robinson, P; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 65, 727-736