A stable-isotope stratigraphy at Site 846 (tropical Pacific, 3°06'S, 90°49'W, 3307 m water depth), based on the benthic
foraminifers Cibicides wuellerstorfi and Uvigerina peregrina, yields a high-resolution record of deep-sea δ¹⁸O and δ¹³C over the
past 1.8 Ma, with an average sampling interval of 3 k.y. Variance in the δ¹⁸O...
The sorbed gases at all four Ocean Drilling Program Leg 139 sites (855, 856, 857, and 858) showed the unmistakable presence of thermogenic hydrocarbons. No indication of abiogenic gas was found. The evidence for the thermogenic hydrocarbons includes elevated contents of higher hydrocarbons (i.e., C₁/[C₂ + C₃] ca. 2-20), δ¹³CCH₄...
The accelerated diagenesis, maturation, and catagenesis of organic matter to hydrothermal petroleum was studied in sediments from Ocean Drilling Program Leg 139 in Middle Valley, northern Juan de Fuca Ridge. Sediments at Sites 855 and 856 have experienced high heat flow resulting in accelerated diagenesis of the immature organic matter...
We carried out a detailed rock magnetic and paleomagnetic study of deep-sea sediments from selected intervals of Site 1233 in order to assess whether they contain reproducible evidence for submillennial-scale environmental, climatic, and geomagnetic field variability. Three 1.5-m sediment intervals from oxygen isotope Stages 1, 2, and 3 were sampled...
Carbonate nodules and associated sediments from Ocean Drilling Program Leg 139 sites of the Middle Valley, Juan de Fuca Ridge, were studied using a combination of inorganic and organic geochemical techniques. The mineralogy and stable isotopic compositions defined three types of nodules, reflecting the conditions of carbonate precipitation. Nodule ingrowth...
The shallow sections of most holes drilled during Ocean Drilling Program Leg 139 contain alkenones derived from prymnesiophyte algae. The alkenones indicate a paleotemperature of the photic zone in the upper ocean during primary carbon fixation of 7°-15°C, with an average of 10.7°C. Based on laboratory hydrous pyrolyses these alkenones...
Sediments from five Leg 167 drill sites and three piston cores were analyzed for C[subscript ORG] and CaCO₃. Oxygen isotope stratigraphy on benthic foraminifers was used to assign age models to these sedimentary records. We find that the northern and central California margin is characterized by k.y.-scale events that can...
High-temperature combustion oxidation measurements of nonvolatile dissolved organic carbon (DOC) have been determined for pore waters from sediments of Middle Valley, Ocean Drilling Program Leg 139, as well as for overlying and near-bottom seawater. The DOC values in the interstitial waters are generally greater than those in the overlying water...
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...
The central purposes of this study were to review the
historical sources of David Kolb's formulation of experiential
learning theory, and to determine the effect and
application of Kolb's theory and Learning Style Inventory
as reflected in the literature between 1971 and 1990.
It was found that Kolb based his...
Agonistic behavior among three species of Microtus live-trapped
near Corvallis, Oregon was recorded in order to interpret habitat
segregation by the species in areas of syrnpatry. The method used to
measure agonistic interaction was similar to that of Colvin (1970).
Agonistic behavior was recorded under red light in a neutral...
The data presented in this report demonstrate significant improvements
in the ability to constrain trace element and Sr isotopic
concentrations in sediments overlying ridge-flank hydrothermal
systems. Improved sampling methods orchestrated by the Integrated
Ocean Drilling Program (i.e., advanced piston coring and
anoxic sample processing) enabled the collection of reactive pore...
High resolution, continuous records of GRAPE wet bulk density (a carbonate proxy) from Ocean Drilling Program Leg 138
provide one the opportunity for a detailed study of eastern equatorial Pacific Ocean carbonate sedimentation during the last 6 m.y.
The transect of sites drilled spans both latitude and longitude in the...
A publication containing advice on a wide range of gardening topics, including composting, container gardens, fall/winter gardens, fertilizing, insect pests, plant diseases, planting guidelines, raised beds, site selection, slugs, soil improvement, tilling, warm-season crops, watering, and weeds. Includes regional tips for various parts of Oregon.
Full Text:
a good chance you can garden almost year-round with a little extra effort. Many cool-season crops
Establishing true depths of recovered sediments is critical to determining sedimentation rates for high-resolution paleoclimatic
studies. We have corrected the composite depth scale, which accounts for the entire continuous sedimentary sequence, so that sediment
depths are consistent with logging depths, or "true" depths. We accomplished this by taking advantage of...
An exact integral solution for the moisture profile in growing fingers in sandy soil is derived from Richards' equation. The solution provides moisture content along a finger as a function of position and time and provides applicable results, including the calculation of the asymptotic matric potential of a growing finger...