D.B. Moore
1965
Recent coastal sediments Double Point to Point San Pedro, California
Paper
Hydraulic Engineering Laboratory Technical Report
HEL-2-14
Berkeley, CA
University of California
"This study seeks to examine patterns of long term sediment movement along a portion of the California coast centering around the mouth of San Francisco Bay. Naturally-occurring heavy minerals were used to trace the influence of the several sources of sediments. Surface samples were collected from beaches and from the adjacent portion of the shelf under less than 130 feet of water. The samples obtained were analyzed mechanically and petrographically. Six petrographic provinces were differentiated on the basis of physical and mineralogical properties. It was found that sands south and west of the Golden Gate in less than 60 to 100 feet of water reflect the mineralogy of San Francisco Bay sediment, and samples from the mollusk-rich Bolinas Bay and adjacent areas to the north and west contained large amounts of aragonite. Sediments in 60 to 100 feet of water west of the Golden Gate are unusually high in hornblende and sediments in more than 100 feet of water are somewhat higher in minerals of the Franciscan Formation than sediments closer to the coast. It is concluded from this information that the San Francisco Bay Bar and adjacent sediments south and west of the Golden Gate bridge have been derived principally from San Francisco Bay, and that sediments in the Bolinas Bay area are derived in large part from the decomposition of shells of modern marine organisms. The areas in 60 to 100 feet of water and greater than 100 feet of water do not appear to have any modern sources of sediment and are interpreted as relicts of features developed during lower sands of sea level. Similarities between sediments in more than 100 feet of water in this area and sediments in the same environment to the north of the area studies suggest a less complicate distribution of sediments and perhaps extensive longshore transport of sediments during this lower stand of sea level. The distribution of recent sediments near the coast in the area studies indicates that longshore transport is now only of limited, local importance."
"In the past decade, much interest has been generated in the study of the long term movement of Recent sediments. The present study continues this work, concentrating on the coastal shelf sediments west of Marin and San Francisco Counties, California."
This work was supported by Contract DA-49-055-CIV-ENG-63-4 with the Coastal Engineering Research Center, Corps of Engineers, U.S. Army. Samples 1683-1745 from Trask's 1954 study (Collected May 1952 to October 1954) Data digitized by the USGS for inclusion into usSEABED (http://walrus.wr.usgs.gov/usseabed)
1964
Publication date
None planned
-122.7977
-122.4654
37.9456
37.6664
None
University of California at Berkeley
Steel bucket
ISO 19115 Topic Category
Oceans and Estuaries
Location
GeoscientificInformation
NASA/Global Change Master Directory (GCMD) Earth Science Keyword. Version 5.3.3
Marine Sediments
Sedimentary Textures
Terrigenous Sediments
Geographic Names Information System (GNIS)
California
Double Point
Point San Pedro
San Francisco Bay
Bolinas Bay
Golden Gate Bridge
Available at the USGS library and others
Cite D.B. Moore and the University of California, Berkeley as the source of the information
University of California
Mail
Department of Civil and Environmental Engineering
760 Davis Hall
Berkeley
CA
94720-1710
510-642-3261
HEL2-14
Sample distribution with bathymetry and coastline for reference
.jpg
D.B. Moore at the University of California Berkeley for the collection and analysis of data. For inclusion into usSEABED: Digitization: Carolynn Box and Jennifer Mendonca (USGS); Location digitization by Nadine Golden (USGS), Formatting corrections: Jane Reid (USGS) and Chris Jenkins (University of Colorado)
Tkme: Another editor for formal metadata by Peter N. Schweitzer (U.S. Geological Survey, Reston, VA 22092), version 2.9.13, Microsoft Windows Version 5.1; Microsoft Word 2000 9.0
P.D. Trask
1954
San Francisco Bay sediment study
Paper
University of California Institute of Engineering Research
57, issues 1 and 2
Berkeley, CA
University of California
No estimate made for the accuracy of the data in the original report. Data digitized by the USGS and partners were visually compared to the source data, and corrected. Where appropriate, data were tested for completeness using MS Excel. Locations checked using GIS.
Data fall within normal ranges for statistical values.
Data from Appendix: statistical data were digitized by hand (typed in), visually compared to source and corrected as needed.. Heavy mineral percents, carbonate percents, and mineral percents not included in usSEABED.
Navigation by radio compass and ship's compass. Locations were digitized from scanned figure using ArcMap 8.3a.
Depth determination by unspecified fathometer. Water depths recorded in feet.
Samples were washed to remove clay, salt, and organic matter, and sieved.
Unknown
HEL-2-14
University of California
Mail
Department of Civil and Environmental Engineering
760 Davis Hall
Berkeley
CA
94720-1710
510-642-3261
Vector
Point
181
.0001
.0001
Decimal degrees
Point
SDTS point
Source report
Depth
Water depth
Source report
5.5
45.7
Meters
0.1
Median
Median grainsize
Source report
-1.32
3.84
Phi
0.01
Sorting coefficient
Sorting of grainsize
Trask 1932
1.05
3.42
Phi
0.01
University of California
Mail
Department of Civil and Environmental Engineering
760 Davis Hall
Berkeley
CA
94720-1710
510-642-3261
HEL Report 2-14
Although this dataset has been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data. Users of the data should be aware of limitations of the data due to possible imprecision due to navigational inaccuracies and limitations of the statistical data.
Report is available at some libraries.
None
None
1966
2005
U.S. Geological Survey
Jane A. Reid
Geologist
Physical and mail
400 Natural Bridges Drive
Santa Cruz
CA
95060
831-427-4727
jareid@usgs.gov
email preferred
CSDGM Version 2
FGDC-STD-001-1998
None
Metadata was written by a user of the data. Any information contained in the physical report is authoritative and supercedes any information given here.