Mineralogical compositions of sediment samples from the San Francisco Bay coastal system

The mineralogical compositions of 119 samples collected from throughout the San Francisco Bay coastal system, including bayfloor and seafloor, area beaches, cliff outcrops, and major drainages, were determined using X-ray diffraction (XRD). Comparison of the mineral concentrations and application of statistical cluster analysis of XRD spectra allowed for the determination of provenances and transport pathways. The use of XRD mineral identifications provides semi-quantitative compositions needed for comparisons of beach and offshore sands with potential cliff and river sources, but the innovative cluster analysis of XRD diffraction spectra provides a unique visualization of how groups of samples within the San Francisco Bay coastal system are related so that sand-sized sediment transport pathways can be inferred. The main vector for sediment transport as defined by the XRD analysis is from San Francisco Bay to the outer coast, where the sand then accumulates on the ebb tidal delta and also moves alongshore. This mineralogical link defines a critical pathway because large volumes of sediment have been removed from the Bay over the last century via channel dredging, aggregate mining, and borrow pit mining, with comparable volumes of erosion from the ebb tidal delta over the same period, in addition to high rates of shoreline retreat along the adjacent, open-coast beaches. Therefore, while previously only a temporal relationship was established, the transport pathway defined by mineralogical and geochemical tracers support the link between anthropogenic activities in the Bay and widespread erosion outside the Bay. The XRD results also establish the regional and local importance of sediment derived from cliff erosion, as well as both proximal and distal fluvial sources. This research is an important contribution to a broader provenance study aimed at identifying the driving forces for widespread geomorphic change in a heavily urbanized coastal-estuarine system.

Social and economic characteristics of Spanish-origin hired farmworkers in 1973 /

"Revised version of a paper presented to the annual meeting of the Rural Sociological Society, San Francisco, Calif., August 1975."

Planning and scheduling work zone traffic control - technical report. Final report.

Federal Highway Administration, Office of Research, Washington, D.C.

State of the art: residential traffic management.

Federal Highway Administration, Office of Research, Washington, D.C.

Effective treatments of over and undercrossings for use by bicyclists, pedestrians and the handicapped. Final report.

Federal Highway Administration, Office of Research and Development, Washington, D.C.

Successful methods of teaching English to bilingual children in Seattle public schools,

"This pamphlet reports the findings of one of the investigations undertaken during 1936-37 under the Project in Research in Universities of the Office of Education ... The project was financed under the Emergency Relief Appropriation Act of 1935 and conducted in accordance with administrative regulations of the Works Progress Administration." -Foreword.

Desegregation of the nation's public schools : a status report.

Includes bibliographical references.

Human relations : a guide for leadership training in the public schools : summary report on a project with the Syracuse, New York, school system.

Cover title.

The Puerto Rican study, 1953-1957; a report on the education and adjustment of Puerto Rican pupils in the public schools of the city of New York

Mode of access: Internet.

The Californian.

Editor: 1891-, C.F. Holder.

Fourth annual education conference on problems of segregation and desegregation of public schools : May 3-4, 1962, Washington, D.C.

Includes index.

Planning and scheduling work zone traffic control. Executive summary.

Federal Highway Administration, Office of Research, Washington, D.C.

Planning and scheduling work zone traffic control. Final technical report.

Federal Highway Administration, Office of Research, Washington, D.C.

Planning and scheduling work zone traffic control. User's guide.

Federal Highway Administration, Office of Research, Washington, D.C.

Lessons learned in the D.C. public schools : hearing before the Subcommittee on Oversight of Government Management, Restructuring, and the District of Columbia of the Committee on Governmental Affairs, United States Senate, One Hundred Fifth Congress, second session, March 9, 1998.

Shipping list no.: 98-0336-P.