U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA.
2020
April 2018 bathymetry (NAVD88) of Coyote Creek and Alviso Slough, South San Francisco Bay, California
raster digital data
https://doi.org/10.3133/ofr20111315
U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA.
2020
Bathymetry and Digital Elevation Models of Coyote Creek and Alviso Slough, South San Francisco Bay, California (Version 5, Revised 2020)
Version 5.0
U.S. Geological Survey Open-File Report
2011-1315
https://doi.org/10.3133/ofr20111315
http://pubs.usgs.gov/of/2011/1315
1-m resolution bathymetry collected in Coyote Creek and Alviso Slough in April 2018.
Projection = UTM, zone 10 in meters,
Horizontal Datum = NAD83 (CORS96),
Vertical Datum = NAVD88, all units in meters.
The surveys extend east from Calaveras Point along Coyote Creek to the railroad bridge,
along Alviso Slough to the town of Alviso (just over 7 km), and along the 3.7 km of Guadalupe
Slough closest to the San Francisco Bay, California.
To monitor bathymetric change as the South Bay Salt Pond Restoration Project progresses
(http://www.southbayrestoration.org).
Additional information about the field activities from which these
data were derived is available online at:
https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-632-FA
Any use of trade, product, or firm names is for descriptive purposes only
and does not imply endorsement by the U.S. Government.
20180416
20180417
ground condition
As needed
-122.060187436
-121.974560855
37.4706742088
37.4231662547
USGS Metadata Identifier
USGS:8ebb7e68-47f1-422a-a728-250ddfe01da3
ISO 19115 Topic Category
elevation
inlandWaters
oceans
USGS Thesaurus
bathymetry
bathymetry measurement
digital elevation models
interferometric sonar
sidescan sonar
GPS measurement
None
U.S. Geological Survey
USGS
Coastal and Marine Hazards and Resources Program
CMHRP
Pacific Coastal and Marine Science Center
PCMSC
Data Categories for Marine Planning
Bathymetry and Elevation
Marine Realms Information Bank (MRIB) keywords
geographic information systems (GIS)
wetland restoration
Geographic Names Information System (GNIS)
State of California
San Francisco Bay
Alameda County
Santa Clara County
Alviso
Coyote Creek
Alviso Slough
Guadalupe Slough
None
USGS-authored or produced data and information are in the public
domain from the U.S. Government and are freely redistributable with
proper metadata and source attribution.
Please recognize and acknowledge the U.S. Geological Survey as the
originator of the dataset and in products derived from these data.
This information is not intended for navigational purposes.
USGS Pacific Coastal and Marine Science Center
Amy Foxgrover
Geographer
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
USA
(831) 460-7561
(831) 427-4748
afoxgrover@usgs.gov
Amy C. Foxgrover
Bruce E. Jaffe
Gerald T. Hovis
Craig A. Martin
James R. Hubbard
Manoj R. Samant
Steve M. Sullivan
2007
2005 Hydrographic Survey of South San Francisco Bay, California
Open-File Report
2007-1169
Reston, VA
U.S. Geological Survey
http://pubs.usgs.gov/of/2007/1169
Applied Microsystems Ltd.
2005
SVplus sound velocity, temperature, and depth profiler user's manual
User's manual
revision 1.23
T. Soler
R.A. Snay
2004
Transforming positions and velocities between the International Terrestrial Reference
Frame of 2000 and North American Datum of 1983
Journal article
Journal of Surveying Engineering, v. 130, no. 2
These bathymetric data have not been independently verified for accuracy.
All bathymetric values are derived from the same instruments and processing workflow.
The raw bathymetry data were filtered in SEA Swath Processor and imported into CARIS HIPS and SIPS for post-processing.
Within CARIS a swath angle BASE (Bathymetric with Associated Statistical Error) surface was created at 1 m resolution and the
subset editor used to manually eliminate any remaining outliers or artifacts. The average depth within each 1 by 1 m cell was exported
as an ASCII text file and imported into Surfer for interpolation using a linear kriging algorithm with a 1-simga nugget of 0.05 m and a
2 by 2 m search radius. The resultant grid was exported to ESRI ArcMap software for display.
Uncertainty in the horizontal position of each sounding is a function of the total uncertainty propagated through
each of the following component instruments: 1) base station GPS, 2) vessel GPS, 3) inertial
motion unit (IMU), 4) water sound velocity model, and 5) beam spreading in the water column. Assuming no
systematic errors in the measurement instruments themselves, beam spreading is the dominate source
of positional uncertainty. The 1-degree sonar beam of the SWATHplus-M results in horizontal uncertainty ranging
from 0.10 m at 10 m slant range, to about 0.45 m at 50 m slant range.
After filtering the data to remove obvious outliers, the standard deviation of the remaining sounding elevations
was calculated for each 1 m by 1 m cell (each containing 19 soundings on average) in CARIS. The mean
of the standard deviation for all cells in the survey is 0.06 m.
Additional uncertainty associated with the vertical datum conversion from NAVD88 to MLLW has not been
assessed.
U.S. Geological Survey, Coastal and Marine Hazards and Resources Program
2018
USGS CMHRP Field Activity 2018-632-FA
raster digital data
https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-632-FA
online
20180416
20180417
ground condition
2018-632-FA
This 2018 field activity collected bathymetric data in San Francisco Bay.
Bathymetric surveys were conducted using a 234.5 kHz SEA (Systems Engineering and Assessment Ltd)
SWATHplus-M phase-differencing sidescan sonar. The sonar was pole-mounted on the 34-foot USGS
mapping vessel R/V Parke Snavely, and affixed to a hull brace. GPS position data were passed through
an Applanix Position and Motion Compensation System for Marine Vessels POS/MV inertial measurement
unit (IMU) to the sonar hardware and data-collection software.
Sonar heads, GPS antennae, and the IMU were surveyed in place to a common reference frame with a
Geodimeter 640 Total Station. The R/V Snavely was outfitted with three networked workstations
and a navigation computer for use by the captain and survey crew for data collection and initial
processing.
2018
An Applanix Position and Motion Compensation System for Marine Vessels (POS/MV) was used to accurately determine the
survey vessel's position. The POS/MV utilizes Global Navigation Satellite System (GNSS) data in combination with angular
rate and acceleration data from the IMU and heading data from the GPS Azimuth Measurement Systems (GAMS) to produce accurate
position and orientation information through a virtual network of base stations. As opposed to receiving high-accuracy Real-Time
Kinematic (RTK) corrections, the POS records raw inertial and GNSS data while surveying, which is later refined through
post processing to incorporate publicly available GPS data from nearby base stations. During post processing the POS/MV
data is run through POSPac software to produce a Smoothed Best Estimate of Trajectory (SBET) file, which is then imported
back into Swath Processor to produce high-accuracy positions relative to the WGS84 ellipsoid. The RMS results from our
POS/MV surveys show positional errors of less than 5 cm in X, Y, and Z.
2018
Sound velocity measurements were collected continuously with an Applied Micro Systems Micro SV deployed
on the transducer frame for real-time sound velocity adjustments at the transducer-water interface. The Micro
SV is accurate to +/- 0.03 m/s. In addition, sound velocity profiles (SVP) were collected with an Applied Micro
Systems, SvPlus 3472. This instrument provides time-of-flight sound-velocity measurements by using invar rods
with a sound-velocity accuracy of +/- 0.06 m/s, pressure measured by a semiconductor bridge strain gauge to an
accuracy of 0.15 percent (Full Scale) and temperature measured by thermistor to an accuracy of 0.05 degrees
Celsius (Applied Microsystems Ltd., 2005).
2018
GPS data and measurements of vessel motion (heave, pitch, and roll) are combined in the POS/MV hardware to
produce a high-precision vessel attitude packet. This packet is transmitted to the Swath Processor acquisition
software in post-processing and combined with instantaneous sound velocity measurements at the transducer
head before each ping. Up to 20 pings per second are transmitted with each ping consisting of 2048 samples
per side (port and starboard). The returned samples are projected to the seafloor using a ray-tracing algorithm
working with the previously measured sound velocity profiles in SEA Swath Processor (version 3.12.7). A
series of statistical filters are applied to the raw samples that isolate the seafloor returns from other
uninteresting targets in the water column. Finally, the processed data are stored line-by-line in both raw (.sxr)
and processed (.sxp) trackline files.
2018
The raw bathymetry data were filtered in SEA Swath Processor (version 3.12.7) and imported into
CARIS HIPS and SIPS (version 11.2) for post-processing. Within CARIS a swath angle BASE
(Bathymetric with Associated Statistical Error) surface was created at 1 m resolution and the
subset editor used to manually eliminate any remaining outliers or artifacts. The average depth
within each 1 by 1 m cell was exported as an ASCII text file and imported into Surfer (version 10)
for interpolation using a linear kriging algorithm with a 1-simga nugget of 0.05 m and a 2 by 2 m
search radius. The resultant grid was exported to ESRI ArcMap (version 10.7.1) for display and
further analyses. The entire survey was shoaled by 4 cm to account for a combination of biases
resulting from changes in the boat instrumentation and configurations that occurred since the
initial survey was collected in 2010.
2018
To convert the bathymetry from WGS84 ellipsoid heights to the tidal datum of MLLW
the data were first transformed from WGS84(ITRF2000) to the NAD83(CORS96) ellipsoid
using a 14-point Helmert transformation described by Soler and Snay (2004) using the
command line tool CS2CS in the Proj4 library (http://trac.osgeo.org/proj/). A fixed
Geoid09 offset of -32.62 m was then applied to convert the NAD83 ellipsoid heights to
orthometric heights NAD83(CORS96)/NAVD88. The orthometric NAVD88 elevations were
converted to MLLW using the conversions provided by the CO-OPS division of NOAA for a
2005 bathymetric survey of South San Francisco Bay (Foxgrover and others, 2007).
2018
Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.
20201019
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
raster
grid cell
6850
4991
Universal Transverse Mercator
10
0.9996
-123
0.0
500000
0.0
row and column
1.0
1.0
meters
North American Datum of 1983 (CORS96)
Geodetic Reference System 80
6378137
298.257
North American Vertical Datum 1988 (NAVD88)
0.01
meters
Attribute values
Altitude
Orthometric altitude (elevation) relative to NAVD88 in meters. Values are positive up.
USGS Open-File Report: 2011-1315
U.S. Geological Survey, Pacific Coastal and Marine Science Center (PCMSC)
Amy Foxgrover
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
US
831-460-7561
831-427-4748
afoxgrover@usgs.gov
These data are available in both X,Y,Z text file format and ESRI ASCII Raster format.
Both formats are contained in a single zip file (Apr_2018.zip), which also includes
CSDGM FGDC-compliant metadata.
Unless otherwise stated, all data, metadata and related materials are considered to
satisfy the quality standards relative to the purpose for which the data were collected.
Although these data and associated metadata have been reviewed for accuracy and completeness
and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or
implied is made regarding the display or utility of the data on any other system or for general
or scientific purposes, nor shall the act of distribution constitute any such warranty.
ESRI ASCII Raster
The ASCII file consists of header information containing a set of keywords, followed by cell values in row-major
order. The file format is:
>
><NCOLS xxx>
><NROWS xxx>
><XLLCENTER xxx | XLLCORNER xxx>
><YLLCENTER xxx | YLLCORNER xxx>
><CELLSIZE xxx>
>{NODATA_VALUE xxx}
>row 1
>row 2
>.
>.
>.
>row n
>
where xxx is a number, and the keyword nodata_value is optional and defaults to -9999. Row 1 of the data is
at the top of the grid, row 2 is just under row 1 and so on. The nodata_value is the value in the ASCII file to
be assigned to those cells whose true value is unknown. In the grid they will be assigned the keyword NODATA.
Cell values are delimited by spaces. No carriage returns are necessary at the end of each row in the grid
(although they are included in this case). The number of columns in the header is used to determine when a
new row begins. The number of cell values is equal to the number of rows times the number of columns.
206
https://doi.org/10.3133/ofr20111315
http://pubs.usgs.gov/of/2011/1315/
No cost
20201019
Amy Foxgrover
U.S. Geological Survey, Pacific Coastal and Marine Science Center
mailing and physical
2885 Mission Street
Santa Cruz
California
95060
USA
(831) 460-7561
afoxgrover@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998