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Marlene A. Noble

Publications and source records attributed to Marlene A. Noble.

22 records · Page 2Linked to original sources

The Monterey Submarine Canyon, California, CTD Data Report Part C: The R/V Robert Gordon Sproul Cruise S-1-94-MB, Aug. 17 - 22, 1994

In August 1993, a program was begun to study the mechanisms that govern the circulation within and the transport of sediment and water through Monterey Submarine Canyon. This is a very large, deep submarine canyon off central California that incises the continental margin from the outer slope to close to the coastline. A key component of the study was to document the interactions between circulation patterns above the canyon, within the canyon, and past the mouth of the canyon. The first part of this program entailed deploying a set of six moorings to measure current, temperature, salinity, and water clarity for one year within Monterey Canyon. The information from the moorings can be found in the U. S. Geological Survey Open File Report 95-838. In the second part of this program, which is the subject of this report, four cruises were conducted during August 1993 to November 1994 within Monterey Bay and along the Monterey Canyon to collect salinity, temperature, and water clarity data with depth (CTD data). The data from each of the four cruises are presented in detail in four separate reports. This report describes and depicts the data collected from the RN Robert Gordon Sproul cruise S-1-94-MB (labeled in our reports as S-1-94-MB).

California↗

Tidal currents and anticyclonic motions on two North Pacific seamounts

Near-bottom currents were measured for several days at three sites on the summits of Fieberling Guyot (32°26′N, 127°46′W) and Horizon Guyot (19°15′N, 160°00′W). Three moorings comprised of two current meters were deployed on each summit; two moorings were deployed on opposite sides of the rim of the summit and one mooring was deployed near the center of the summit. The observed currents were strong, with maximum speeds of 48 and 24 cm s −1 on Fieberling and Horizon, respectively. The currents at specific frequencies were enhanced relative to those in the surrounding ocean. Diurnal currents were the dominant component of the current field on Fieberling Guyot. They accounted for 39–68% of the energy and had amplitudes around 12 cm s −1 . We suspect that these diurnal currents were waves trapped over the seamount. Semidiurnal internal tidal currents were the strongest currents over Horizon Guyot, with amplitudes around 4 cm s −1 . The flow patterns determined in this study seemed to affect the biological and geological characteristics of the seamounts.

Deep Sea Research Part A, Oceanographic Research P↗

Long-term observations of bottom conditions and sediment movement on the Atlantic continental shelf; time-lapse photography from instrumented tripod

An instrument system that measures bottom current, temperature, light transmission, and pressure, and that photographs the bottom at 2- to 6-hour intervals has been developed to study sediment transport on the Atlantic Continental Shelf. Instruments have been deployed extensively along the United States East Coast Continental Shelf for periods of from 2 to 6 months to study the frequency, direction, and rate of bottom sediment movement, and the processes causing movement. The time-lapse photographs are used to (1) characterize the bottom benthic community and surface microtopography; (2) monitor changes in the bottom topography and near-bottom water column caused by currents and storms (for example, ripple generation and migration, sediment resuspension); and (3) monitor seasonal changes in the bottom benthic community and qualitative effects of this community on the bottom sediments.

Conference Paper↗