Vitrinite reflectance of ODP Leg 139 samples (Table 1)

Isolated kerogens from four sites in the Middle Valley hydrothermal region of the Juan de Fuca Ridge (Ocean Drilling Project (ODP) Leg 139) were analysed by electron paramagnetic resonance (EPR) spectroscopy. Measurements of peak width, spin density and power saturation for site 857 kerogens, which increased regularly in maturity downhole, show correlation with vitrinite reflectance values from 0.61 to 2.5%, indicating the start of the oil window at depths from 200 to 400 m. Spin density increases to 1.56 * 10**17 spins per gram and peak width decreases to 3.45 G (gauss) with increasing depth. The tendency to power saturate also decreases with increasing maturity and increasing vitrinite reflectance within the oil window. These trends are consistent with a model in which exchange processes are occurring and cause changes in the EPR behavior of samples from this site. Sediments from other Middle Valley sites, 855, 856 and 858 contain large quantities of pyrite with Mn2+ impurities which interact with the carbon radical to distort the EPR measurements.

(Table 1) Abundance of selected diatom taxa in the mid-Pliocene of ODP Hole 167-1022A

Diatom assemblages from the middle part of the Pliocene (3.2-2.5 Ma) were investigated from Ocean Drilling Program Sites 1016, 1021, and 1022 in an effort to infer paleotemperature fluctuations off California. Diatoms are very sparse in virtually all of the samples that were examined from Sites 1016 and 1021. This is presumably because these sites were seaward (west) of the coastal zone of diatom productivity during the middle part of the Pliocene. Diatoms are relatively common in the vast majority of samples that were examined from Hole 1022A. Diatom assemblages are dominated by Chaetoceros spores (a coastal upwelling component), the cold-water (subarctic) taxa Neodenticula kamtschatica and its descendant Neodenticula koizumii, and Thalassionema nitzschioides, a temperate taxon that is typically found at the seaward edge of coastal upwelling zones. Paleotemperature interpretations, however, are not possible at this time because of the scarcity of comparative modern core-top data.

(Table T1) Trace element concentration and isotopic composition of pore waters from ODP Leg 168 sites

Pore water was collected from each of 10 sites during Ocean Drilling Program (ODP) Leg 168 on the eastern flank of the Juan de Fuca Ridge. These ten sites delineate a transect perpendicular to the present ridge axis and span a crustal age of 0.86-3.59 Ma. At nine of the ten sites the entire sediment section, which ranged from 41.3 to 613.8 m thick, was cored and attempts were made to recover at least one whole round of sediment per section of core for extraction of pore water. Several (2-5) whole-round sediment samples were taken from the uppermost and lowermost cores to constrain the chemical gradient near the sediment/water and sediment/basalt interfaces, respectively. Pore water was extracted from whole-round sediment core sections by squeezing only the most pristine sediment in a titanium squeezer designed by Manheim and Sayles (1974). Two additional water samples were collected in situ using the water-sampler temperature probe (WSTP; Barnes, 1988, doi:10.2973/odp.proc.ir.110.104.1988). Both of these samples were collected in the cased section of the open borehole from ODP Hole 1026B. Formation fluids were flowing up the cased hole into the overlying deep seawater (Fisher et al., 1997, doi:10.1029/97GL01286). Detailed descriptions of the sampling methods that were used to collect fluids are given by the Shipboard Scientific Party (Davis, Fisher, Firth, et al., 1997, doi:10.2973/odp.proc.ir.168.1997).

Compilation of maximum ingestion and maximum clearance rate data for marine pelagic organisms

The metabolic rate of organisms may either be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law; or it may be considered a property of the organism that emerges as a result of the organism's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from previous compilations by other authors. Data were read from tables or digitized from graphs. Only measurements made on individuals of know size, or groups of individuals of similar and known size were included. We show that clearance and respiration rates have life-form-dependent allometries that have similar scaling but different elevations, such that the mass-specific rates converge on a rather narrow size-independent range. In contrast, ingestion and growth rates follow a near-universal taxa-independent ~3/4 mass scaling power law. We argue that the declining mass-specific clearance rates with size within taxa is related to the inherent decrease in feeding efficiency of any particular feeding mode. The transitions between feeding mode and simultaneous transitions in clearance and respiration rates may then represent adaptations to the food environment and be the result of the optimization of tradeoffs that allow sufficient feeding and growth rates to balance mortality.

Data on the biogeochemical cycle of methane in the ocean

Geological, mineralogical and microbiological aspects of the methane cycle in water and sediments of different areas in the oceans are under consideration in the monograph. Original and published estimations of formation- and oxidation rates of methane with use of radioisotope and isotopic methods are given. The role of aerobic and anaerobic microbial oxidation of methane in production of organic matter and in formation of authigenic carbonates is considered. Particular attention is paid to processes of methane transformation in areas of its intensive input to the water column from deep-sea hydrothermal sources, mud volcanoes, and cold methane seeps.

Geochemical composition of calcite and aragonite, and characteristics of hydrothermal fluids of ODP Leg 168 sites

During Leg 168 a transect was drilled across the eastern flank of the Juan de Fuca Ridge in an area where the volcanic basement is covered by sediments of variable thickness. Samples of basement volcanic rocks were recovered from nine locations along the transect, where the basement sediment interface is presently heated to temperatures varying from 15° to 64°C. Altered rocks with secondary calcium carbonate were common at four of the sites, where present-day temperatures range from 38° to 64°C. Fluid inclusions in aragonite suggest that the mineral precipitated from an aqueous fluid of seawater salinity at temperatures well below 100°C. The chemical compositions of secondary calcite and aragonite were determined with both an electron microprobe and a laser-ablation inductively coupled plasma-mass spectroscopy (LA-ICP-MS) microprobe. These two techniques yielded consistent analyses of the same minor elements (Mg and Sr) in the same specimens. The combined results show that secondary aragonites contain very little Mg, Mn, Fe, Co, Ni, Cu, Zn, Rb, La, Ce, Pb, or U, yet they contain significant Sr. In contrast, secondary calcites contain significant Mg, Mn, Fe, Ni, Cu, Zn, and Pb, yet very little Co, Rb, Sr, La, Ce, or U. Secondary calcium carbonates provide subseafloor reservoirs for some minor and trace elements. Replacement of aragonite by calcite should result in a release of Sr, Rb, and Zn to solution, and it provides a sink for Mg, Mn, Ni, Cu, Zn, and Pb.

Raw and normalized X-ray fluorescence (XRF) scannings of IODP Expedition 321, Site U1338

We used X-ray fluorescence (XRF) scanning on Site U1338 sediments from Integrated Ocean Drilling Program Expedition 321 to measure sediment geochemical compositions at 2.5 cm resolution for the 450 m of the Site U1338 spliced sediment column. This spatial resolution is equivalent to ~2 k.y. age sampling in the 0-5 Ma section and ~1 k.y. resolution from 5 to 17 Ma. Here we report the data and describe data acquisition conditions to measure Al, Si, K, Ca, Ti, Fe, Mn, and Ba in the solid phase. We also describe a method to convert the data from volume-based raw XRF scan data to a normalized mass measurement ready for calibration by other geochemical methods. Both the raw and normalized data are reported along the Site U1338 splice.