U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA., 2011, 2010 Bathymetric Survey and DEM of Corte Madera Bay, California: U.S. Geological Survey Open-File Report OF2011-1217.Online Links:
This is a raster data set. It contains the following raster data types:
Planar coordinates are encoded using row and column
Abscissae (x-coordinates) are specified to the nearest 10.0
Ordinates (y-coordinates) are specified to the nearest 10.0
Planar coordinates are specified in meters
The horizontal datum used is World Geodetic System 1984 (G1150).
The ellipsoid used is WGS 84.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/298.257.
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Bathymetry of Corte Madera Bay collected for use in wave-attenuation studies and sea level rise analyses.
U.S. Geological Survey, Coastal and Marine Geology Program, USGS CMG Field Activity S-3-10-SF.Online Links:
U.S. Geological Survey, Coastal and Marine Geology Program, USGS CMG Field Activity S-9-10-SF.Online Links:
This bathymetric data has not been independently verified for accuracy.
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) intertial 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 x 1 m cell (each containing over 400 soundings on average) in CARIS. The mean of the standard deviation for all cells in the Corte Madera survey is 0.06 m and 98% of the cells in the data set have a standard deviation of less than 0.15 m.
Two separate bathymetric surveys of Corte Madera Bay were conducted: the first (USGS Field Activity ID: S-3-10-SF) from January 26 - 29, 2010 and the second (USGS Field Activity ID: S-9-10-SF) on March 29 and 30, 2010. The combined bathymetric surveys consist of 215 survey lines covering an area of approximately 6.5 square km extending north to the dredged ferry channel leading to Corte Madera Creek and to the south, just beyond Paradise Cay Yacht Harbor.
All bathymetric values are derived from the same instruments and processing workflow.
Are there legal restrictions on access or use of the data?
- Access_Constraints:
- If physical samples or materials are available, constraints on their on-site access are described in "WR CMG Sample Distribution Policy" at URL: <http://walrus.wr.usgs.gov/infobank/programs/html/main/sample-dist-policy.html>
- Use_Constraints:
- Not suitable for navigation.
Read and fully comprehend the metadata prior to data use.
Acknowledge the U.S. Geological Survey (USGS), the Originator, when using the data set as a source. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Share data products developed using the source data set with the Originator.
Data should not be used beyond the limits of the source scale.
This information is not intended for navigational purposes.
The data set is NOT a survey document and should not be utilized as such. Some USGS information accessed through this means may be preliminary in nature and presented without the approval of the Director of the USGS.
This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the responsibility of the user.
831-427-4757 (voice)
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Downloadable Data
This information is not intended for navigational purposes.
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Please recognize the U.S. Geological Survey (USGS) as the source of this information. Physical materials are under controlled on-site access. Some USGS information accessed through this means may be preliminary in nature and presented without the approval of the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the responsibility of the user.
| Data format: |
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 be 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. in format ESRI ASCII Grid (version 1.0) Size: 23 MB (compressed) |
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| Network links: |
<https://pubs.usgs.gov/of/2011/1217/> |
831-427-4785 (voice)
afoxgrover@usgs.gov
