Transition metal and rare earth element (REE) data are presented
for various sedimentary materials from two Manganese Nodule
Program (MANOP) sites in the eastern tropical Pacific. These data
constrain the sources of elemental supply to the seafloor and the
processes that control ferromanganese nodule genesis. Investigation
of elemental partitioning between...
File scanned at 300 ppi (Monochrome) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Examination of polished sections of manganese micronodules
from metalliferous sediments from the Bauer Deep reveals sequences
of ferromanganese deposition which are consistent for micronodules
from a single sediment sample and imply a common depositional
history for members of such assemblages. The relatively simple
'stratigraphy' of manganese micronodules, as compared to...
Easter Island and Sala y Gomez are part of the Sala y Gomez
Ridge, a broad band of high topography and scattered seamounts
extending ESE from the East Pacific Rise. It has been proposed that
the Sala y Gomez Ridge results from the movement of the Nazca Plate
over a...
Time series records of horizontal current velocity, temperature, light attenuation
and settling particle flux obtained using moored instruments above Endeavour Ridge in
the northeast Pacific Ocean elucidate the dynamics of a deep-sea, neutrally buoyant,
hydrothermal plume. Data collected in four mooring deployments over three years
within 20 km of an...
The Blanco Trough, a deep depression located in the Blanco Fracture Zone near the intersection with the Juan de Fuca Ridge, contains unusual manganese-enriched layered sediments. Due to the Blanco Trough's bathymetric isolation and confinement, and its location in a tectonically active zone, three hypotheses concerning the origin and cause...
Subsurface hydrothermal activity dominates the heat and salt budgets of the deep water column in Crater Lake, Oregon. From a time series of conductivity-temperature-depth data and data from a thermistor chain mooring, we estimate that the net hydrothermal heat flow is ~1 W m⁻² and the corresponding salt flux is...
As a result of the past three years of field studies and our interpretation of these and other data from the literature, we conclude that there are inputs of hydrothermal fluids into the bottom of Crater Lake. The dissolved materials associated with these thermally and chemically enriched fluids, coupled with...
This study examined the effects of a group treatment of Self-Instructional
Training (S.I.T.) with an institutionalized aged (65
or over) population. The purpose of the S.I.T. program was to
increase the positive content of speech elicited in a structured
social interaction. S.I.T., as developed for this study, followed
Meichenbaum's three...
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...
Flux estimates show that upward mixing of the deep-water nitrate pool accounts for more than 85% of the total new nitrogen input to the euphotic zone of Crater Lake. Because measured primary productivity (360 mg C m-2 d-1) is 10–30 times higher than a level supported solely by the input...
Active inputs of thermally and chemically enriched fluids at the bottom of Crater Lake create small vertical and horizontal heterogeneities in the deep-lake temperature and salt distribution. Using an internally recording CTD and a precise definition for salinity as a function of in situ conductivity and temperature, we assess the...
Major (Fe, Mn, Al) and minor (Cr, Mo, Pb, Zn, Cd) element
analyses of metalliferous sediments in cores from the East Pacific
Rise and Bauer Deep indicate that the Bauer Deep sediments are
similar in chemistry and origin to metalliferous sediments of the
East Pacific Rises.
Fe, Pb, and Zn...
This thesis investigates lithogenic sediments on the Siberian Arctic shelf, their sources, modes of dispersal, transport pathways and post-depositional diagenetic alteration. Working with cores collected from the Chukchi, East Siberian and Laptev Seas, we characterize surface-sediment elemental chemistry and clay mineralogy. We identify five regions with endmember sedimentary compositions. Comparing...