A new technique for determining the amount of opal in deep-sea
sediments of any age is described. Using a normative calculation, a
portion of the analytical silica concentration of sediments is subtracted
as non-biogenic in proportion to the concentration of aluminum in the
sample. The ratio of SiO₂:Al₂O₃ used to...
Many ocean regions important to the global carbon budget, including the equatorial Pacific Ocean, have low chlorophyll concentrations despite high levels of conventional nutrients. Iron may instead by the limiting nutrient, and elevated input of terrigenous Fe during windy glacial episodes has been hypothesized to stimulate oceanic productivity through time...
In order to quantify changes in export production and carbonate dissolution over the past 1 Myr in the
central equatorial Pacific Ocean we analyzed Ba, P, Al, Ti, and Ca in 1106 samples from five piston cores gathered from
5°S to 4°N at 140°W. We focused on Ba/Ti, Al/Ti, and...
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...
Sediment spectral reflectance measurements were generated aboard the JOIDES Resolution during Ocean Drilling Program Leg 162 shipboard operations. The large size of the raw data set (over 1.3 gigabytes) and limited computer hard disk storage space precluded detailed analysis of the data at sea, although broad band averages were used...
Calcium carbonate percentages at five Ceara Rise sites were estimated at 1- to 2-k.y. intervals over the past 5 m.y., using
reflectance spectroscopy and magnetic susceptibility proxies. From these estimates and detailed correlations between sites, gradients
of calcite and terrigenous sediment accumulation rates in a depth transect of sites reveal...
Ocean Drilling Program (ODP) Leg 138 was designed to study the late Neogene paleoceanography of the equatorial Pacific Ocean at time scales of thousands to millions of years. Crucial to this objective was the acquisition of continuous, high-resolution sedimentary records. It is well known that between successive advanced piston corer...
The primary objective of Leg 138 was to provide detailed information about the ocean's response to global climate change
during the Neogene. Two north south transects were drilled (95° and 110°W) within the region of equatorial divergence driven
upwelling (and thus high accumulation rates and resolution) and spanning the major...
Multivariate statistical treatments of large data sets in sedimentary geochemical and other fields are
rapidly becoming more popular as analytical and computational capabilities expand. Because
geochemical data sets present a unique set of conditions (e.g., the closed array), application of generic
off-the-shelf applications is not straightforward and can yield misleading...
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Kyte, F. T., M. Leinen, G. R. Heath, and L. Zhou (1993), Ce-
nozoic sedimentation history of the
This dissertation examines the impact of the German naturalist and literary figure Johann Wolfgang von Goethe’s ideas on twentieth century Anglophone plant morphology and biology. Goethe interpreted the organ forms of flowering plants as metamorphoses of each other. His literary, historical, and philosophical writings suggest themes of alienation from and...