Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA. Publication_Date: 2015 Title: October 2014 bathymetry (WGS84) of Coyote Creek and Alviso Slough, South San Francisco Bay, California Geospatial_Data_Presentation_Form: raster digital data Larger_Work_Citation: Citation_Information: Originator: U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA. Publication_Date: 2015 Title: Bathymetry and Digital Elevation Models of Coyote Creek and Alviso Slough, South San Francisco Bay, California (Version 3, Revised 2015) Edition: Version 3.0 Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: OF2011-1315 Online_Linkage: http://pubs.usgs.gov/of/2011/1315, http://dx.doi.org/10.3133/ofr20111315 Description: Abstract: 1-m resolution bathymetry collected in Coyote Creek and Alviso Slough in October 2014. Projection = UTM Zone 10 in meters, Horizontal Datum = WGS84(G1150), Elevations relative to the WGS84 Ellipsoid, all units in meters. The surveys extend east from Calaveras Point along Coyote Creek to approximately 2 km west of 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 San Francisco Bay, California. Purpose: To monitor bathymetric change as the South Bay Salt Pond Restoration Project progresses (http://www.southbayrestoration.org). Supplemental_Information: USGS Field Activity 2014-670-FA Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20141023 Ending_Date: 20141024 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -122.060187436 East_Bounding_Coordinate: -121.974560855 North_Bounding_Coordinate: 37.4706742088 South_Bounding_Coordinate: 37.4231662547 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme_Keyword: inlandWaters Theme_Keyword: oceans Theme: Theme_Keyword_Thesaurus: GCMD SCIENCE PARAMETERS Theme_Keyword: OCEANS > BATHYMETRY > SEAFLOOR TOPOGRAPHY > BATHYMETRY Theme: Theme_Keyword_Thesaurus: GCMD INSTRUMENT PARAMETERS Theme_Keyword: SIDE-SCAN SONAR Theme_Keyword: GPS > Global Positioning System Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: State of California Place_Keyword: San Francisco Bay Place_Keyword: Alameda County Place_Keyword: Santa Clara County Place_Keyword: Alviso Place_Keyword: Coyote Creek Place_Keyword: Alviso Slough Place_Keyword: Guadalupe Slough 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: This information is not intended for navigational purposes. Read and fully comprehend the metadata prior to data use. Uses of these data should not violate the spatial resolution of the data. Where these data are used in combination with other data of different resolution, the resolution of the combined output will be limited by the lowest resolution of all the data. Acknowledge the U.S. Geological Survey in products derived from these data. Share data products developed using these data with the U.S. Geological Survey. This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Although this Federal Geographic Data Committee-compliant metadata file is intended to document these data in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: USGS Pacific Coastal and Marine Science Center Contact_Person: Amy Foxgrover Contact_Position: Geographer Contact_Address: Address_Type: physical address Address: 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Country: USA Contact_Voice_Telephone: (831) 460-7561 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: afoxgrover@usgs.gov Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: This bathymetric data has not been independently verified for accuracy. Logical_Consistency_Report: All bathymetric values are derived from the same instruments and processing workflow. Completeness_Report: The raw bathymetry data was 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. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: 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. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: 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 0.05 m and 97% of the cells in the data set have a standard deviation of less than 0.15 m. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey, Coastal and Marine Geology Program Publication_Date: 2015 Title: USGS CMG Field Activity 2014-670-FA Geospatial_Data_Presentation_Form: raster digital data Online_Linkage: Type_of_Source_Media: online Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20141023 Ending_Date: 20141024 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: 2014-670-FA Source_Contribution: This 2014 field activity collected bathymetric data in San Francisco Bay. Process_Step: Process_Description: Sonar Data Collection The bathymetric surveys were conducted using a 234.5 kHz SEA (Systems Engineering & 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 a POS MV intertial 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. Process_Date: 2014 Process_Step: Process_Description: Vessel Position and Attitude Vessel and position attitude measured using an Applanix Position and Orientation System for Marine Vessels (POS MV). 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 RTK corrections in real time, 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 M/V 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 5cm in X, Y, and Z. Process_Date: 2014 Process_Step: Process_Description: Sound Velocity Measurements 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). Process_Date: 2014 Process_Step: Process_Description: Sonar Sounding Processing GPS data and measurements of vessel motion 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 real-time 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 3.7.17). 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 is stored line-by-line in both raw (.sxr) and processed (.sxp) trackline files. Process_Date: 2014 Process_Step: Process_Description: Digital Elevation Model Production The raw bathymetry data was filtered in SEA Swath Processor (version 3.7.17) and imported into CARIS HIPS and SIPS (version 8.1) 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 10.2.1) for display and further analyses. The entire survey was shoaled by 7 cm to account for a combination of biases resulting from changes in the boat instrumentation and configurations that occured since the initial survey was collected in 2010. Process_Date: 2014 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Raster_Object_Information: Raster_Object_Type: grid cell Row_Count: 5062 Column_Count: 6916 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 10 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -123 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 1.0 Ordinate_Resolution: 1.0 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: WGS84 Ellipsoid_Name: WGS84 (G1150) Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: WGS84 Altitude_Resolution: 0.01 Altitude_Distance_Units: meters Altitude_Encoding_Method: Attribute values Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Altitude Entity_Type_Definition: Altitude (elevation) above the WGS84 (G1150) ellipsoid in meters. Values are positive up. Entity_Type_Definition_Source: USGS Open-File Report: 2011-1315 Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center (PCMSC) Contact_Person: Amy Foxgrover Contact_Address: Address_Type: mailing and physical address Address: 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Country: US Contact_Voice_Telephone: 831-460-7561 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: afoxgrover@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: This information is not intended for navigational purposes. This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ESRI ASCII Grid Format_Version_Number: 1.0 Format_Information_Content: The ASCII file consists of header information containing a set of keywords, followed by cell values in row-major order. The file format is: > > > > > > >{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. Transfer_Size: 50 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2011/1315/, http://dx.doi.org/10.3133/ofr20111315 Fees: No cost Metadata_Reference_Information: Metadata_Date: 20150623 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Amy Foxgrover Contact_Address: Address_Type: mailing address Address: 400 Natural Bridges Drive City: Santa Cruz State_or_Province: California Postal_Code: 95060 Country: USA Contact_Voice_Telephone: (831) 460-7561 Contact_Electronic_Mail_Address: afoxgrover@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998