ALBERT

Description: Despite an absence of freshwater exploitation, the adult salmon run in the Matamek River, Quebec, declined during 1975-1980 to 〈23% of the level thought to occur there prior to 1967. Returns in 1979 and 1980 of adults tagged as smolts were 1.0% and 0.9%, respectively. Numbers of emigrating smolts and their corresponding adult returns are not significantly correlated, although we observed a trend towards more salmon (2 sea year fish) returning with larger numbers of migrating smolts. Since 1967 there is noted a decrease in the age at which returning adults smolted and females appear to now constitute a larger percentage of returning grilse and salmon. These, and other changes in life history characteristics, appear to be caused solely by commercial exploitation.

Description: Prepared by the Woods Hole Oceanographic Institution and the Department of Recreation, Fish and Game of the Province of Quebec.

Description: The Seafloor Borehole Array Seismic System (SEABASS) was originally developed to record autonomously on the seafloor the signals received on a four-sonde three-component borehole geophone array in the VLF band (2-50Hz)(Stephen eta!., 1994). The system is designed to use the wireline re-entry capability (Spiess, 1993; Spiess eta!., 1992) to install and retrieve the seafloor instrumentation (Figures 1 and 2). Following the successful demonstration of this technology on the LFASE (Low Frequency Acoustic-Seismic Experiment) project in September 1989, it was decided to extend the capability to broadband (1000sec-5Hz) borehole seismometers which could be used for permanent seafloor seismic observatories in the Ocean Seismic Network (Orcutt and Stephen, 1993; Purdy and Dziewonski, 1988; Purdy and Orcutt, 1995; Stephen, 1995; Sutton and Barstow, 1990; Sutton eta!., 1988; Sutton eta!., 1965). The Broadband Borehole Seismic System (B3S2) is the prototype system for permanent broadband borehole seismic observatories on the seafloor. It has three major components: i) a broadband borehole seismometer, the Teledyne 54000, modified for seafloor operations by Scripps-IGPP; ii) the re-entry system provided by Scripps-MPL; and iii) the seafloor recording system developed by WHO I. Because of the similarity of the seafloor recording system to SEABASS we have named this new system SEABASS-ll. This report discusses the development of SEABASS-Il at WHOI in the period from July 14, 1992 to January 31, 1996. The motivation for the project and a work statement are contained in WHOI proposals 7016 and 7016.1. This report is a collection of documentation prepared while the work was being carried out. Some of the issues discussed in early memos were subsequently changed. Modifications and further testing of SEABASS-ll, as well as final system integration tests with the borehole andreentry systems (both of which are also still being modified and tested) have still to be carried out in preparation for the OSN Pilot Experiment Cruise in Spring 1997. This is a preliminary report only and presents work in progress. It will be useful to the engineering team as a historical reference of the sequence of events in the development of SEABASS-ll but it should not be considered as a technical manual for the instrumentation.

Description: A 21-cm diameter sphincter corer (Burke, 1968) has been modified by mounting it in a tripod frame. This modification results in more dependable recovery of undisturbed surficial sediment and greater penetration into firm sediment. The device is useful in water depths from 2-6000 m, is adaptable for use on small boats, is very easily employed on large research vessels, and can be readily disassembled for more convenient transporting and storing.

Description: Funding was provided by the U.S. Department of Energy under Contract EY-76-C-3563, Sandia National Laboratory under Contract 37/3164 and the U.S. Nuclear Regulatory Commission under Contract NRC- 04-76-349.

Description: The broadband borehole seismic system (B3S2) is being developed as one component of the Ocean Seismic Network (OSN) Pilot Experiment which will be carried out at the OSN-1 Site off Hawaii in Winter 1998. The other major instruments being developed for the experiment are a Broadband Ocean Bottom Seismometer and a Shallow Buried Broadband Ocean Bottom Seismometer. B3S2 consists of four major components: 1) a borehole sonde with a re-entry guide, Teledyne 54000 broadband seismometer, and REFTEK digitizing system, 2) a seafloor acquisition and recording system (SEABASS), 3) a control vehicle for deploying the sonde in a borehole, and 4) shipboard command and control electronics. The deployment system is very similar to the SEABASS configuration used on LFASE (Stephen eta!, 1994). The purposes of the tests at Pinon Flat were: 1) to integrate the borehole sonde and seafloor and shipboard electronics which had been constructed by different groups: WHOI and SIO/IGPP; 2) test the combined subsystem in a wet borehole environment using actual cables and simulating seafloor conditions; and 3) acquire seismic ambient noise and earthquake data over approximately a three month period for comparison with known stations at the Pinon Flat Observatory.

Description: This work was carried out under NSF Grants No. OCE-91-18943 and OCE No. OCE-95-05730: "A Broadband Borehole Seismometer for the Deep Ocean - Development and Land Testing"

Description: From the Forward: The idea for an Exploratory Workshop on Fisheries Sociology emerged from informal discussions held at the 1983 Rural Sociological Society meetings. Planning for the Exploratory Workshop was undertaken by the two of us (Bailey and Harris) with the assistance of Peter Sinclair and Christopher Vanderpool. We sought to identify persons working in different areas of the sociology of fisheries who could present review papers on their areas of inquiry. The papers in this volume are the result of that effort. At the same time, we sought to identify persons who would be interested in attending such a workshop• By combining our personal networks, the mailing list of the Fisheries Anthropologist at the National Marine Fisheries Service (Peter Fricke), and the list of attendees at two sessions on fisheries organized by Bailey at the 1984 Rural Sociological Society meetings, we developed a mailing list of 83 sociologists working on some aspect of fisheries. Invitations to attend the workshop were sent to those persons. In response to the invitation, 24 sociologists attended the Workshop. They came from eleven states, the District of Columbia and Puerto Rico, three provinces of Canada, and Norway. They represented work in both industrialized and developing nations, in subsistence, recreational and commercial fisheries, and in aquaculture.

Description: This report was prepared with funds from the American Sociological Society; U.S. Department of Commerce, NOAA, Office of Sea Grant under Grant Number NA84AA-D-00033 (R/S-12); and the J . N. Pew, Jr. Charitable Trust.

Description: The Coastal Research Center activities for the period of 1984 to 1986 are described briefly. Major projects include: Assimilative Capacity-Buzzards Bay, Georges Bank book; Instrumentation-Experimental Seawater Flume, Sea Level Change - Measurement and Consequences; and Fisheries Ecology. General activities are also described.

Description: Prepared under grants from the Andrew W. Mellon Foundation, the Richard King Mellon Foundation, and the Mobil Foundation, Incorporated.

Description: This project was initiated to accomplish the necessary research and documentation of existing seismic techniques and systems for the study of sediments and sedimentary structures in the oceans. In this respect , it is an 'inventory' of methods and techniques for looking at small-scale features or changes in structures lying from 10 to 1000 m beneath the sea floor. It attempts to assess the vertical and lateral resolution capabilities of existing and technically feasible seismic systems. Some of the questions posed are: how closely can we determine vertical variation such as sediment layer thickness and vertical variation with depth; also lateral coherence or its disruption by such agents as facies changes, thinning or thickening, slumping, faulting; the nature of the basement structure, its areal coherence, velocity structure and associated anomalies?

Description: Prepared for the Sandia Laboratories under Contract 13-9944.

Description: Also published as: Journal. of Marine Research 38 (1980): 215-248

Description: As a sequel to Schmitz and Hogg (1978), nine-month moored observations of current and temperature from the Charlie Gibbs Fracture Zone are further described, and then interpreted in terms of low frequency quasigeostrophic motions. Large vertical and horizontal changes are observed in the variance of both mean and fluctuating components. It is demonstrated that these changes could be associated with the (complex) nature of the topography. With regard to the mean flow, it is shown through an advective model that the topography is sufficiently steep to force this motion to closely follow isobaths. Time-dependent motions for periods from 2 to 96 days are described using the technique of empirical orthogonal functions. The most energetic mode is always bottom trapped, with flow oriented along isobaths at lower frequencies and approaching equipartition of along- and cross-isobath motions at higher frequencies. At the lowest frequencies a second mode which increases upward in energy is also judged significant, while for periods shorter than 3.6 days the second mode is again highly bottom trapped. We interpret these motions using linear wave theory. There is relatively close correspondence between theory and observation when the effects of both large- and small-scale topographic features are included in the model calculations. In addition to the usual topographic wave, the abrupt slope changes on the north wall allow for a baroclinic fringe mode with a ncar bottom node at low frequencies and small-scale bottom corrugations force highly bottom trapped waves above the smooth slope cut-off frequency.

Description: Prepared for the Office of Naval. Research under Contract N00014-76-C-0197; NR 083- 400.

Description: Also published as: Journal of the Acoustical Society of America 68 (1980): 602-612

Description: A new technique for the measurement of the plane-wave reflection coefficient of a horizontally stratified ocean bottom is described. It is based on the exact Hankel transform relationship between the reflection coefficient and the bottom reflected field due to a point source. The method employs a new algorithm for the numerical evaluation of the Hankel transform which is based on the "projection-slice" theorem for the two-dimensional Fourier transform. The details of the algorithm are described in the companion paper. Although the algorithm is applied to the case of an isovelocity ocean, the general theory for measuring the plane-wave reflection coefficient in a refracting ocean is developed. The technique provides information about the reflection coefficient, not only for real incident angles, _but also for complex angles, thus potentially providing substantial additional structural information about the bottom. The method is shown to yield excellent results with synthetically generated data for the cases of a hard bottom and slow isovelocity bottom.

Description: Prepared for the Office of Naval Research under Contracts N00014-77-C-0196 and N00014-75-C-0951; NR 049-328.

Description: Also published as: Journal of the Acoustical Society of America 68 (1980): 602-612

Description: The effects of normal modes in the bottom on the acoustic field in the ocean are examined. The ocean bottom model consists of a slow isovelocity layer overlying an isovelocity half-space to simulate the characteristic sound velocity drop at the water-bottom interface. Attention is focused on the perfectly trapped modes which are excited in the layer by inhomogeneous waves emitted by a point source in the water column. The relative normal mode contribution to the total acoustic field in the water is calculated analytically for a near-bottom source/receiver geometry and evaluated for representative ocean bottom examples. It is shown that, for combined source/receiver heights less than a wavelength, the field is dominated by the leaky mode contribution at short ranges ( $ 2 km) and the trapped mode contribution at long ranges ( ~ 2 km). For fixed bottom parameters, the trapped mode contribution increases exponentially with decreasing combined source/receiver height. It is also shown that, for a fixed layer wavenumber-thickness product and fixed layer sound speed, the leaky mode fields at different frequencies are approximately range-scaled versions of the same field.

Description: Prepared for the Office of Naval Research under Contract N000 14-77-C-0196.