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Ediz Hook (Inside), Port Angeles Harbor, Washington, Bathymetry (Cruise ID: S-6-10-PS)

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Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator:
U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), Santa Cruz, CA.
Publication_Date: 2011
Title:
Ediz Hook (Inside), Port Angeles Harbor, Washington, Bathymetry (Cruise ID: S-6-10-PS)
Geospatial_Data_Presentation_Form: raster digital data
Series_Information:
Series_Name: U.S. Geological Survey Open-File Report
Issue_Identification: 1226
Online_Linkage: <https://pubs.usgs.gov/of/2011/1226/>
Description:
Abstract:
Between February 22, 2010 and March 3, 2010 the U.S. Geological Survey, Pacific Coastal and Marine Science Center mapped the bathymetry and acoustic backscatter of the Elwha River Delta, Strait of Juan de Fuca, Washington State. In addition to the main survey, 3 small surveys of interest to USGS partners were conducted on February 26, 2010. The first is the area surrounding the abandoned Rayonier Pier site in Port Angeles Harbor, the second is a former log-storage facility on the southern side of Ediz Hook near the Port Angeles Coast Guard station. Both of these smaller surveys were conducted during a weather day where sea conditions were too rough for surveying outside the harbor breakwaters. In addition, several lines of data were collected on the outer face of Ediz hook as the vessel transited to and from the Elwha river delta to inspect failure features along the northen edge of Ediz Hook first observed in 2005 during USGS cruise K-1-05-PS.

The surveys were conducted using the research vessel R/V Parke Snavely outfitted with an interferometric sidescan sonar for swath mapping and Real-Time Kinematic navigation equipment for accurate shallow water operations.

Purpose:
Preliminary bathymetry and coastal habitats assessment for change detection prior to Elwha dam removal.
Supplemental_Information:
The URL for USGS field activity S-6-10-PS is <http://walrus.wr.usgs.gov/infobank/s/s610ps/html/s-6-10-ps.meta.html> The URL for USGS field activity K-1-05-PS is <http://walrus.wr.usgs.gov/infobank/k/k105ps/html/k-1-05-ps.meta.html>
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20100222
Ending_Date: 20100302
Currentness_Reference: ground condition
Status:
Progress: complete
Maintenance_and_Update_Frequency: as needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -123.43617035521
East_Bounding_Coordinate: -123.45012687582
North_Bounding_Coordinate: 48.141881989435
South_Bounding_Coordinate: 48.137626581146
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificinformation
Theme_Keyword: oceans
Place:
Place_Keyword_Thesaurus: Geographic Names Information System (GNIS)
Place_Keyword: USA
Place_Keyword: State of Washington
Place_Keyword: Strait of Juan de Fuca
Place_Keyword: Port Angeles Harbor
Place_Keyword: Ediz Hook
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.

Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USGS Pacific Coastal and Marine Science Center
Contact_Person: David P Finlayson
Contact_Position: Geologist
Contact_Address:
Address_Type: physical address
Address: U.S. Geological Survey
Address: 400 Natural Bridges Drive
City: Santa Cruz
State_or_Province: CA
Postal_Code: 95060
Country: USA
Contact_Voice_Telephone: (831) 427-4757
Contact_Facsimile_Telephone: (831) 427-4748
Contact_Electronic_Mail_Address: dfinlayson@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 Ediz Hook survey was a secondary target of opportunity conducted on 26 February 2010. The survey extends along 1 kilometer of shoreline on the south side of Ediz Hook (in Port Angeles Harbor). The survey extends from shallow water offshore approximately 200 m with complete coverage within the area of interest.
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 x 1 m cell (each containing 28 soundings on average) in CARIS. The mean standard deviation for all cells in the survey is 0.23 m and 95% of the cells in the data set have a standard deviation of less than 0.50 m. Some of the vertical uncertainty can be attributed to the large quantity of sunken logs protruding from the seafloor in this location.
Lineage:
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. Real-time kinematic (RTK) GPS position data were passed through a CodaOctopus F180 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: 20100222
Process_Step:
Process_Description:
Geodetic Control

Geodetic control for the survey was established using a shore based Global Positioning System (GPS) base station broadcasting Real Time Kinematic (RTK) corrections to the survey vessel via UHF radio link. The base station was located at the base of Ediz Hook. The base station was programmed using the WGS84 (G1150) reference frame with an Epoch of 2010.1548. Average Opus Solution coordinates for the station are:

Reference Frame: WGS84 (G1150) Epoch: 2010.1548 Latitude: N 48° 08 06.01943 Longitude: W 123° 28 06.90674 Ellipsoid Height: -11.355m

The average values for the derived OPUS solution for MILL are: Reference Frame: ITRF00 [same as WGS84 (G1150)] Epoch: 2010.1548 Latitude: N 48° 08 06.01936 Longitude: W 123° 28 06.90685 Ellipsoid Height: -11.351m

The differences to be added to the RTK broadcast locations are: Latitude: -0.00007 Longitude: +0.00011 Ellipsoid Height: +0.004m

Using UTM coordinates as a comparison: The base station was programmed using the following coordinates: Reference Frame: NAD83, UTM zone 10 Epoch: 2002.0000 Northing: 5331411.376m Easting: 465138.251m Ellipsoid Height: -11.042m Orthometric Height: 9.155m (based Geoid09)

Process_Date: 20100222
Process_Step:
Process_Description:
Vessel Position and Attitude

The R/V Snavely was equipped with a CodaOctopus F180 attitude and positioning system for the duration of the survey. The F180 is running F190 firmware, and receives real-time kinematic (RTK) corrections directly. The RTK GPS data (2 cm error ellipse) are combined with the inertial motion measurements directly within the F190 hardware so that high-precision position and attitude corrections are fed in real-time to the sonar acquisition equipment. The WGS84 (G1150) Epoch 2010.1548 3-dimensional reference frame was used for all data acquisition.

Process_Date: 20100222
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: 2010022
Process_Step:
Process_Description:
Sonar Sounding Processing

GPS data and measurements of vessel motion are combined in the F180 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 3.05.18.04). 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. Processed (.sxp) files were further processed with sxpegn (build 151) by David Finlayson (USGS) to remove erroneous data from the files and make valid gain-normalized amplitude data for processing backscatter data.

Process_Date: 2010022
Process_Step:
Process_Description:
Digital Elevation Model Production

The digital elevation model (DEM) produced in this work is solely derived from the bathymetric data collected by the USGS during field activity S-6-10-PS. CARIS HIPS and SIPS (version 7.0.2 Service Pack 2) was used to clean and bin the raw bathymetry. Processed .sxp files were imported to CARIS, and field sheets were created within CARIS to encompass the survey area.

Survey lines were filtered to remove adjacent line data from nadir gaps. A CARIS Swath Angle BASE (Bathymetric with Associated Statistical Error) surface was created at 1 m resolution and the subset editor was used to clean artifacts and other unwanted soundings. The binned data were exported as an ASCII table along with calculations of the bin standard deviation (of all soundings within the 1 m x 1 m cell spacing) and the sounding density.

To convert the data from ITRF2000 (also known as WGS84 G1150) ellipsoid heights to orthometric heights on NAD83 (CORS96)/NAVD88, the Caris gridded data was exported as an ASCII table. The data was next transformed from the the ITRF2000 ellipsoid to the NAD83 (CORS96) ellipsoid using a 14-point Helmert transformation using the parameterization described in Soler and Snay (2004) with the command line tool CS2CS in the Proj4 library (<http://trac.osgeo.org/proj/>). The parameters were calculated for an Epoch date of 2010.1548. The conversion from WGS84 (G1150)/ITRF2000 to NAD83 (CORS96) shifts the data about +0.90 m to the east, -0.80 m to the south, and +0.30 m in elevation.

At the basestation location, the NAD83 ellipsoid height was -11.04 m and the orthometric height based on Geoid09 was 9.16m, representing a vertical offset of 20.2 m between the NAD83 ellipsoid heights and NAVD88. This static offset was applied to the dataset to convert the NAD83 (CORS96) ellipsoid elevations into NAVD88 altitudes. Finally, the ASCII data were gridded in Surfer at 1-m resolution using the IDW algorithm with a 3 m search radius and a smoothing parameter set to 0.25 (the smoothing parameter here accounts for the horizontal uncertainty in the sounding position). This process filled small gaps in the surface and provided some minor smoothing through the statistical noise inherent to interferometric bathymetry. This surface was converted to ESRI ASCII grid format using Surfer's conversion tools.

Process_Date: 20110320
Process_Step:
Process_Description:
Backscatter Image Production

The raw 16-bit backscatter recorded simultaneously with the bathymetry by the SWATHplus was georefrenced and gain-normalized by the program SXPEGN, software purpose written by the USGS to enhance the backscatter of the SWATHplus system. The program normalizes for time-varying signal loss and beam directivity differences. The resulting normalized amplitude values are re-scaled to 16-bit, exported as point files and gridded into GeoJPEGS using GRID Processor Software supplied by SEA.

Process_Date: 20110320

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: raster
Raster_Object_Information:
Raster_Object_Type: grid cell
Row_Count: 468
Column_Count: 1042

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: World Geodetic System 1984 (G1150)
Ellipsoid_Name: WGS 84
Semi-major_Axis: 6378137
Denominator_of_Flattening_Ratio: 298.257
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name: World Geodetic System 1984 (G1150)
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

Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
U.S. Geological Survey, Pacific Coastal and Marine Science Center (PCMSC)
Contact_Person: David P Finlayson
Contact_Address:
Address_Type: mailing and physical address
Address: U.S. Geological Survey
Address: 400 Natural Bridges Drive
City: Santa Cruz
State_or_Province: CA
Postal_Code: 95060-5792
Country: US
Contact_Voice_Telephone: 831-427-4757
Contact_Facsimile_Telephone: 831-427-4748
Contact_Electronic_Mail_Address: dfinlayson@usgs.gov
Resource_Description: Downloadable Data
Distribution_Liability:
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.

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:

<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.
Transfer_Size: 381 MB
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <https://pubs.usgs.gov/of/2011/1226/>
Fees: No cost

Metadata_Reference_Information:
Metadata_Date: 20110411
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Pacific Coastal and Marine Science Center (PCMSC), US Geological Survey
Contact_Address:
Address_Type: mailing address
Address: U.S. Geological Survey
Address: 400 Natural Bridges Drive
City: Santa Cruz
State_or_Province: California
Postal_Code: 95060
Country: USA
Contact_Voice_Telephone: 8314274757
Contact_Electronic_Mail_Address: dfinlayson@usgs.gov
Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998

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URL: https://pubs.usgs.gov/of/2011/1226/
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