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...
The aqueous chemistries of two transition metal cations, Zr⁴⁺ and Nb⁵⁺, are examined and then used to develop inorganic precursor solutions. The oxides of these cations (ZrO₂ and Nb₂O₅) are deposited and characterized, and their morphological and optical properties discussed. Due to the obstacles created by niobium's aqueous chemistry, an...
With the emergence of big data and the Open Data Movement, and the wide availability to the public of large databases, Data Literacy is a necessary learning goal for students. Understanding the data process in its entirety is now a vital skillset required across industry, government, and scientific disciplines. The...
Benthic incubation chambers have been deployed in a variety of geochemical environments that provide a comprehensive geochemical framework from which to address issues related to Ba geochemistry and the use of Ba as a paleoproxy. First order budgets for barium show that in the equatorial Pacific, present rates of Ba...
Carbon isotopically based estimates of CO₂ levels have been generated from a record of the photosynthetic fractionation of ¹³C (≡εp) in a central equatorial Pacific sediment core that spans the last ~255 ka. Contents of ¹³C in phytoplanktonic biomass were determined by analysis of C37 alkadienones. These compounds are exclusive...
Application of the ²³⁰Th normalization method to estimate sediment burial fluxes in six cores from the
eastern equatorial Pacific (EEP) reveals that bulk sediment and organic carbon fluxes display a coherent regional
pattern during the Holocene that is consistent with modern oceanographic conditions, in contrast with estimates
of bulk mass...
Holocene hemipelagic deposition of terrigenous silts and clays
dominates sedimentation on most of the Oregon and Washington continental
slope. The sources of these sediments, the mechanisms causing sediment
dispersal, and the relative contributions of the various continental
sources to the marine deposits have been investigated using quantitative
mineral and geochemical...
Benthic chamber measurements of the reactants and products involved with biogenic matter diagenesis (oxygen, ammonium, nitrate, silicate, phosphate, TCO₂, alkalinity) were used to define fluxes of these solutes into and out of the sediments off southern and central California. Onshore to offshore transects indicate many similarities in benthic fluxes between...
We use flux, dissolution, and excess ²³⁰Th data from the Joint Global Ocean Flux Study and Manganese Nodule Project equatorial Pacific study Site C to assess the extent of sediment focusing in the equatorial Pacific. Measured mass accumulation rates (MAR) from sediment cores were compared to reconstructed MAR by multiplying...
The mass accumulation rates of sedimentary components (carbonate, organic carbon, opal, barite, reactive phosphate, iron, terrigenous minerals, etc.) are used in many paleoceanographic reconstructions to learn about temporal and spatial changes in surficial Earth processes including wind stress and direction, oceanic circulation, weathering rates, marine productivity and ecosystem structure, climate...
Three stations, at ∼80 m water depth on the Oregon shelf between 44.7°N and 43.9 N, were studied under hypoxic conditions in late spring and summer of 2009 to determine benthic oxygen consumption rates. Oxygen fluxes were derived from eddy correlation (EC) measurements made from an autonomous lander deployed for...
Nitrogen isotopes are an important tool for evaluating past biogeochemical cycling from the paleoceanographic record. However, bulk sedimentary nitrogen isotope ratios, which can be determined routinely and at minimal cost, may be altered during burial and early sedimentary diagenesis, particularly outside of continental margin settings. The causes and detailed mechanisms...
Three stations, at similar to ~80 m water depth on the Oregon shelf between 44.7 degrees N and 43.9 N, were studied under hypoxic conditions in late spring and summer of 2009 to determine benthic oxygen consumption rates. Oxygen fluxes were derived from eddy correlation (EC) measurements made from an...
Large barite (BaSO4) structures mark cold seeps in the southern San Clemente Basin. Barium flux to San Clemente sediments is two to three times greater than fluxes measured in surrounding California Borderland basins. Analyses of sediment trap material, water column samples, sediments and pore water indicate that expected bariumbearing mineral...
Dating pelagic clay can be a challenge due to its slow sedimentation rate, post-depositional alteration, and lack of biogenic deposition. Co-based dating techniques have the potential to create age models in pelagic clay under the assumption that the flux of non-detrital Co to the seafloor is spatially and temporally constant,...
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important archive of
ocean history over long time scales (0–85 Myr) [e.g., Rea and Bloomstine, 1986; Leinen
This compilation by the School of Oceanography of Oregon State University lists in chronological order the oceanographic reports published in 1975 and 1976. It also lists theses for which degrees were awarded in 1976. This is the third annual update of our reference 74-1 which brought together a listing of...
Two separate research projects are described here. One involves
development of a new analytical method for determination of Ba in seawater and
other natural waters. The other is a collaborative field study of the chemistry of
Lake Issyk-Kul, Kyrgyzstan.
The method project explored an ion chromatography-fluorescence detection
bench-top approach for...
We examine the 0–100 Ma paleoceanographic record retained in pelagic clay from the South Pacific Gyre (SPG) by analyzing 47 major, trace, and rare earth elements in bulk sediment in 206 samples from seven sites drilled during Integrated Ocean Drilling Program Expedition 329. We use multivariate statistical analyses (Q-mode factor analysis...
Tilapia culture in Yucatan State, Mexico, is largely semi-intensive. The producers are mostly poor farmers who receive government subsidies for purchase of fingerlings and balanced feed. Feeding practices are often inadequate (satiety rations), moreover, producers frequently suffer financial and resource shortfalls. During feed shortages producers are known to use empirical...
We present evidence for pore water flow through the sediment of Crater Lake, Oregon based on systematic variations in pore water chemical compositions and thermal gradients. Pore water was extracted from sediment by centrifugation and diffusive exchange using a gravity corer deployed from a surface vessel and a box corer...
The spring bloom is a key oceanic phenomenon in the Northern Gulf of Alaska (NGA), where it supports the regional ecosystem, fisheries, and CO2 sequestration. Despite its significance, mechanisms that trigger NGA blooms are still debated, largely due to a lack of sufficient data from late winter through spring. New...
In 2013, NSF selected OSU as the lead institution to oversee the design and construction of three new Regional Class Research Vessels (RCRVs), a new class of research ship designed with advanced capabilities for next generation, interdisciplinary, oceanographic operations. The new RCRVs will increase efficiency and the ability to address...
The chemistry of hafnium oxide based and materials are described in the context of ion exchange and lithography. HafSOx, represented by the composition HfO₂₋[subscript x](SO₄)x, is described to possess a significant capacity towards ion exchange in acidic and basic solutions, enabling films of HafSOx to be cleanly and readily be...
This work presents a novel CCRW receiver that utilizes a window of variable width, for e˙ectively mitigating multipath and ambiguity in both civil and military positioning applica-tions using Global Navigation Satellite Systems (GNSS). This CCRW receiver incorporates a single stroboscopic window, whose width is iteratively reduced until the e˙ect of...
Bransfield Strait is a Quaternary, ensialic back arc basin at the transition from rifting
to spreading. Fresh volcanic rocks occur on numerous submarine features distributed
along the rift axis, including a discontinuous neovolcanic ridge similar to the nascent
spreading centers seen in some other back arc basins. Smaller edifices near...
We present concentrations of germanium and silicon in sediment pore waters, basaltic formation fluids,
and bulk sediment from three ridge flank hydrothermal systems (RFHS). Basaltic formation fluids from
warm (>30°C) RFHS have much higher Ge concentrations and Ge:Si molar ratios than overlying sediment
pore waters, requiring seawater-basalt reactions to dominate...
During Leg 138, we measured reflectance spectra in the visible and near-infrared bands (455-945 nm) every few centimeters on split core surfaces from eastern tropical Pacific Ocean sediments. Here, we evaluate predictions of the content of biogenic calcite, biogenic opal, and nonbiogenic sediments from the reflectance spectra. For Sites 844...
The distribution of barite (BaSO₄) in marine sediments has long been studied as a proxy for paleoproductivity. While pure barite is known to be a stable mineral in oxic sediments, it is also known that variations in the Sr/Ba ratio influence its solubility and liability during early diagenesis. To extract...
The prevalence of sexual violence among the college student population has become a significant public health issue. The real magnitude of the problem is unknown since most students do not report incidents of sexual violence. However, some studies have estimated that 1 in 5 students experience sexual violence while in...
During two cruises in February and June of 2003, the erodibility of sediment along the western Adriatic Sea was measured using a "Gust erosion chamber". In addition, the surficial sediment properties were characterized through a suite physical and biological measurements including porosity, grain-size, inorganic carbon, organic carbon and colloidal carbohydrate....
The focus of this study is to develop a general and low-cost solution-based
process to fabricate micro- and nano-structured semiconductors that are suitable
for electronics. This process uses simple metal halide precursors dissolved in a
solvent (organic or aqueous) and is capable of forming uniform and continuous
thin films via...
A nutrient solution technique developed for wheat was used to
determine tolerance of rice cultivars to aluminum (Al) toxicity.
Pre-germinated rice seed was placed on top of a screen and allowed
to grow on the Al-free solution for 72-96 hours or until the primary
root was 2-3 cms long. Seedlings...
This compilation of theses and dissertations (a part of the OSU Bibliographic Series) for the period 1970-1977 reflects this university's emphasis on research and graduate study. It may be viewed as an indicator of the contributions made to the state of Oregon through graduate study and research at Oregon State...
Determination of the source and fate of natural (higher plant lipids, marine
lipids, etc.) and anthropogenically (e.g., petroleum, coal emissions) derived
hydrocarbons and oxygenated compounds in the environment was accomplished
using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS)
to characterize or identify molecular biomarkers to be utilized as tracers....
The production of carbon and export to deep ocean sediments is linked to carbon partitioning between the ocean and atmosphere and is a key driver of climate change over the glacial-interglacial transition. Yet conflicting reconstructions create barriers to understanding changes to the carbon system over this important climate transition. Production...
Climate change policies present multiple quandaries to the field of public policy and science studies. Despite the prevalent scientific consensus, approaches demonstrate great heterogeneity. With one side advocating for the facticity of climate change and a pro-active stance, while the other argues about negative economic trade-offs, viewpoints diverge. Between controversy...
For decades, sexual violence has been a persistent crisis and challenge for universities and colleges across the United States. In order to address this problem and adhere to the strict legal obligations that require post-secondary institutions to prevent sexual violence on their campuses, universities and colleges have implemented a range...
The various solution-based processes, spin coating, inkjet printing, microreactor assisted nanoparticle deposition (MANDTM) and spin-successive ionic layer absorption and reaction (Spin-SILAR) were used to demonstrate thin film electronics and anti-reflective coatings. Several aspects of thin film transistors (TFTs) were tested including a range of temperatures, annealing atmosphere, and deposition methods....