Data report: Diffuse spectral reflectance data from rise sites 1095, 1096, and 1101 and Palmer Deep sites 1098 and 1099 (Leg 178, western Antarctic Peninsula)
The routine use of spectrophotometry on the sediment surfaces of archive halves of each section during the onboard sedimentological core description process is a great stride toward development of real-time
noninvasive characterization of deep-sea sediments. Spectral reflectance data have been used so far for mineral composition studies as well as for lithostratigraphic correlation between sites (Balsam and Deaton, 1991; Balsam et al., 1997; Mix et al., 1995; Ortiz et al., 1999). Their results demonstrate that spectrophotometry can estimate CaCO3 content
by using the 4.65-, 5.25-, and 5.55-μm wavelength spectrums. A detailed overview of various other noninvasive methods is given in Ortiz
and Rack (1999). The purpose of this study is to test whether spectrophotometry in the visible band can be used as a tool to gather further information about grain-size variation, sorting, compaction, and porosity, which are
directly linked to the sedimentation process. From remote sensing data analyses, it is known that diffuse spectral reflectance data in the visible band in the wavelength window of 7.0–6.5 μm are sensitive to grainsize
variations. It appears that a relationship between grain size and signal absorption exists only in this wavelength window. (e.g., Clark, 1999; Gaffey, 1986; Gaffey et al., 1993). Variations in grain size during a sedimentation process are linked to depositional energy, which affects
sorting, compaction, and porosity of sediment deposits. As an example, we study here the spectrophotometric data of the sedimentary sequence of Hole 1098C, which was deposited under widely varying environmental conditions. Alternating turbidite and finely laminated sediments were recovered from Hole 1098C. The turbidites are related
to a high depositional energy environment; the finely laminated sediments are related to a low depositional energy environment. Data from Hole 1098C were therefore used to test whether the spectral reflectance data can provide a proxy for these different depositional environments.
Authors: Wolf-Welling, T.C.W., Cowan, Ellen A., Daniels, J., Eyles, N., Maldonado, A., Pudsey, Carol J.
Editors: Barker, Peter F., Camerlenghi, Angelo, Acton, Gary D., Ramsay, Anthony T.S.
1 January, 2002
In: Barker, Peter F., Camerlenghi, Angelo, Acton, Gary D., Ramsay, Anthony T.S. (eds.). Antarctic glacial history and sea-level change, College Station, Texas, Ocean Drilling Program, 22 pp.