4. Color Reflectance Spectroscopy: a Tool for Rapid Characterization of Deep-sea Sediments

During ODP Leg 138, we tested a prototype instrument, developed at Oregon State University, for measuring light reflectance in 511 channels of the visible and near-infrared bands. The technique of reflectance spectroscopy has been used for some time in chemistry and mineralogy (e.g., Hunt, 1977; Gaffey, 1986) and has found applications in remote sensing of natural reflectance from aircraft and satellites (Hoffer, 1984; Goetz et al., 1982), but this technique has not yet been widely used in marine geology (e.g., Chester and Elderfield, 1966; Barranco et al., 1989). Our goal here is to assess the utility of reflectance spectroscopy as a rapid, nonintrusive tool for characterizing the lithology of deep-sea sediments. In this chapter, we report the instrumentation used for the first time during Leg 138, give a few examples of preliminary shipboard results, and make recommendations about further development of the technique in the context of ocean drilling. A more complete discussion of the scientific results appears elsewhere.