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std_2sigma

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Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator:
U.S. Geological Survey (USGS), Coastal and Marine Geology (CMG), Menlo Park, CA.
Publication_Date: 2010
Title: std_2sigma
Edition: 1
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage: <https://pubs.usgs.gov/ds/514/>
Description:
Abstract:
USGS Western Coastal & Marine Geology scientists mapped the Monterey Bay area from Ano Nuevo to Moss landing between August and December 2009 using a SEA SWATHplus interferometric sonar system. Data were collected as part of the cooperative California Seafloor Mapping program, during field activities S-7-09-MB and S-10-09-MB. Raw sonar data were processed with SEA Swath Processor (version 3.05.18.04) before being cleaned and prepared for CARIS with sxpegn (build 151) by David Finlayson (USGS). Data were then imported to CARIS HIPS and SIPS (version 7.0.1.0 Service Pack 1). Within CARIS, field sheets were created to tile the data into smaller work areas, and survey lines were trimmed to optimize overlap, water column noise was removed, and data were gridded to 2m resolution using a swath angle BASE surface. Standard Deviation values were exported from CARIS as ascii XYZ files and imported to ARCGIS where they were combined into a single grid and multiplied by 2 to give 2 sigma error. Data were then exported as a single continuous ASCII grid
Purpose: California State Waters Mapping
Supplemental_Information:
Information about August-September 2009 field activity data collection at <http://walrus.wr.usgs.gov/infobank/s/s709mb/html/s-7-09-mb.fmeta.faq.html>.

Information about October - December field activity data collection at <http://walrus.wr.usgs.gov/infobank/s/s1009mb/html/s-10-09-mb.fmeta.faq.html>.

Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20090813
Ending_Date: 20091222
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -122.338797
East_Bounding_Coordinate: -121.785351
North_Bounding_Coordinate: 37.111583
South_Bounding_Coordinate: 36.793514
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificinformation
Theme_Keyword: oceans
Theme:
Theme_Keyword_Thesaurus: USGS CMG InfoBank
Theme_Keyword: geoscientific information
Theme_Keyword: bathymetry
Theme_Keyword: oceans
Theme_Keyword: Marine Geology
Place:
Place_Keyword_Thesaurus: Geographic Names Information System (GNIS)
Place_Keyword: Ano Nuevo
Place_Keyword: Moss Landing
Place_Keyword: Monterey Bay
Place_Keyword: California
Place_Keyword: Pacific Ocean
Place:
Place_Keyword_Thesaurus: USGS CMG InfoBank
Place_Keyword: "Monterey Bay, CA"
Place_Keyword: CA
Place_Keyword: Monterey Bay
Place_Keyword: Moss Landing to Ano Nuevo
Place_Keyword: North Pacific Ocean
Place_Keyword: Northern California
Place_Keyword: Northern Pacific Ocean
Place_Keyword: USA
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 Western Coastal & Marine Geology
Contact_Person: David Finlayson
Contact_Position: Operational Geologist
Contact_Address:
Address_Type: physical address
Address: 400 Natural Bridges Drive
City: Santa Cruz
State_or_Province: CA
Postal_Code: 95062
Country: USA
Contact_Voice_Telephone: (831) 427-4757
Contact_Facsimile_Telephone: (831) 427-4748
Contact_Electronic_Mail_Address: dfinlayson@usgs.gov
Browse_Graphic:
Browse_Graphic_File_Name:
<http://walrus.wr.usgs.gov/infobank/s/s709mb/html/s-7-09-mb.index.png>
Browse_Graphic_File_Description:
Illustration of ship tracklines for data collection field activity S-7-09-MB.
Browse_Graphic_File_Type: PNG
Browse_Graphic:
Browse_Graphic_File_Name:
<http://walrus.wr.usgs.gov/infobank/s/s1009mb/html/s-10-09-mb.index.png>
Browse_Graphic_File_Description:
Illustration of ship tracklines for data collection field activity S-10-09-MB.
Browse_Graphic_File_Type: PNG
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.1.3500

Data_Quality_Information:
Logical_Consistency_Report:
These are raw data with uninterpreted results. for updated on this dataset, search for cruise S-7-09-MB and S-10-09-MB on USGS Coastal & Marine Geology InfoBank, or email: dfinlayson@usgs.gov.
Completeness_Report:
GPS Data Collection and Processing

Bathymetric surveys were conducted using a 234.5 kHz SEA (AP) Ltd. SWATHplus-M phase-differencing sidescan sonar. The sonar was pole-mounted on the 34-foot USGS mapping vessel R/V Parke Snavely. The R/V Snavely was equipped with a CodaOctopus F180 attitude and position 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 2002.0 3-dimensional reference frame was used for all measurements.

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).

Sound Velocity Measurements

Sound velocity profile (SVP) measurements were collected on average every two hours throughout the survey. A total of 440 SVPs were collected for this survey. 114 SVPs were collected during cruise S-7-09-MB and 326 SVPs were collected during S-10-09-MB. In general, SVPs were collected every 2 hours, or when the survey vessel moved to a different survey block. Typically two SVPs were collected every four lines. Water column sound velocity profiles varied significantly throughout the survey, however this frequency of SVP collection was sufficient to correct for variations in sound velocity. Only one line from cruise S-7-09-MB (BlockA_230_044) shows an artifact from an uncorrected sound velocity error (smile), for part of it's length. Insufficient sound velocity data were available to correct this line, and no attempt was made to synthesize data.

SVPs were collected with an Applied Micro Systems, SvPlus 3472. This instrument provides time-of-flight sound velocity measurements using invar rods with a sound velocity accuracy of +/- 0.06 m/s, pressure measured by a semiconductor bridge strain gauge to an accuracy to 0.15% (Full Scale) and temperature measured by thermistor to an accuracy of 0.05 C (Applied Microsystems Ltd., 2005). In addition, an Applied Micro Systems Micro SV accurate to +/- 0.03 m/s was deployed on the transducer frame for real-time sound velocity adjustments at the transducer-water interface.

The returned samples are projected to the lake bottom using a ray-tracing algorithm working with 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 lake bottom returns from other uninteresting targets in the water column. Finally, the processed x,y,z, amplitude data is stored line-by-line in both raw (.sxr) and processed (.sxp) trackline files. For this cruise, processed files were filtered across-track with a mean filter at 0.5m resolution.

Bathymetry Processing

Processed (.sxp) files were run through sxpegn (build 151) by David Finlayson (USGS) to remove erroneous data from the files and make valid gain-normalized amplitude data for CARIS HIPS and SIPS (version 7.0.1.0 Service Pack 1) Processed .sxp files were imported to CARIS, and field sheets were created within CARIS and defined to the nearest even integer meter in ground coordinates (WGS84(G1150) UTM Zone 10), to approximately match CA State Waters Quads 36 - 41. Because quads 38 & 39, and quads 40 & 41 had very little horizontal overlap, a horizontal overlap was added to the eastern quads in both cases; that is, the western bounds of quads 39 and 41 were extended to create overlap between field sheets.

Survey line widths were filtered (trimmed) in CARIS to remove adjacent line data from nadir gaps. Target overlap between lines was 25 - 30%, though values ranged from ~10% to <50% depending on line spacing and data quality. CARIS Swath Angle BASE surfaces were then created for each map block at 2m resolution, and the subset editor was used to examine each field sheet and clean artifacts from biological targets and other unwanted soundings. Cleaned data were exported in ASCII xyz format and imported to ArcGIS where they were combined and exported to a single unfilled ESRI ASCII GRID. This is a raw 2m grid of 2 sigma standard deviation of gridded sonar data and no further processing was done on this product.

Positional_Accuracy:

Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Accuracy should be on the order of 2 meters due to datum transformations and grid cell size

Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: U.S. Geological Survey, Coastal and Marine Geology Program
Publication_Date: 2009
Title: USGS CMG S-7-09-MB Metadata
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage:
<http://walrus.wr.usgs.gov/infobank/s/s709mb/html/s-7-09-mb.meta.html>
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20090813
Ending_Date: 20090903
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: S-7-09-MB
Source_Contribution:
Cruise S-7-09-MB contributed swath mapping data from Point Año Nuevo to Table Rock, and a block near Soquel Canyon, in Monterey Bay National Marine Sanctuary. These data are primarily the western 1/3 of the survey area.
Source_Information:
Source_Citation:
Citation_Information:
Originator: U.S. Geological Survey, Coastal and Marine Geology Program
Publication_Date: 2009
Title: USGS CMG S-10-09-MB Metadata
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage:
<http://walrus.wr.usgs.gov/infobank/s/s1009mb/html/s-10-09-mb.meta.html>
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20091012
Ending_Date: 20091126
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: S-10-09-MB
Source_Contribution:
Cruise S-10-09-MB contributed swath mapping data to this survey from Table rock to Moss Landing, in Monterey Bay National Marine Sanctuary. This comprised approximately the eastern 2/3 of the survey area.
Process_Step:
Process_Description:
Data Collection and Processing

Bathymetric surveys were conducted using a 234.5 kHz SEA (AP) Ltd. SWATHplus-M phase-differencing sidescan sonar. The sonar was pole-mounted on the 34-foot USGS mapping vessel R/V Parke Snavely. The R/V Snavely was equipped with a CodaOctopus F180 attitude and position 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 2002.0 3-dimensional reference frame was used for all measurements.

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).

Sound Velocity Measurements

Sound velocity profile (SVP) measurements were collected on average every two hours throughout the survey. A total of 440 SVPs were collected for this survey. 114 SVPs were collected during cruise S-7-09-MB and 326 SVPs were collected during S-10-09-MB. In general, SVPs were collected every 2 hours, or when the survey vessel moved to a different survey block. Typically two SVPs were collected every four lines. Water column sound velocity profiles varied significantly throughout the survey, however this frequency of SVP collection was sufficient to correct for variations in sound velocity. Only one line from cruise S-7-09-MB (BlockA_230_044) shows an artifact from an uncorrected sound velocity error (smile), for part of it's length. Insufficient sound velocity data were available to correct this line, and no attempt was made to synthesize data.

SVPs were collected with an Applied Micro Systems, SvPlus 3472. This instrument provides time-of-flight sound velocity measurements using invar rods with a sound velocity accuracy of +/- 0.06 m/s, pressure measured by a semiconductor bridge strain gauge to an accuracy to 0.15% (Full Scale) and temperature measured by thermistor to an accuracy of 0.05 C (Applied Microsystems Ltd., 2005). In addition, an Applied Micro Systems Micro SV accurate to +/- 0.03 m/s was deployed on the transducer frame for real-time sound velocity adjustments at the transducer-water interface.

The returned samples are projected to the lake bottom using a ray-tracing algorithm working with 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 lake bottom returns from other uninteresting targets in the water column. Finally, the processed x,y,z, amplitude data is stored line-by-line in both raw (.sxr) and processed (.sxp) trackline files. For this cruise, processed files were filtered across-track with a mean filter at 0.5m resolution.

Bathymetry Processing

Processed (.sxp) files were run through sxpegn (build 151) by David Finlayson (USGS) to remove erroneous data from the files and make valid gain-normalized amplitude data for CARIS HIPS and SIPS (version 7.0.1.0 Service Pack 1) Processed .sxp files were imported to CARIS, and field sheets were created within CARIS and defined to the nearest even integer meter in ground coordinates (WGS84(G1150) UTM Zone 10), to approximately match CA State Waters Quads 36 - 41. Because quads 38 & 39, and quads 40 & 41 had very little horizontal overlap, a horizontal overlap was added to the eastern quads in both cases; that is, the western bounds of quads 39 and 41 were extended to create overlap between field sheets.

Survey line widths were filtered (trimmed) in CARIS to remove adjacent line data from nadir gaps. Target overlap between lines was 25 - 30%, though values ranged from ~10% to <50% depending on line spacing and data quality. CARIS Swath Angle BASE surfaces were then created for each map block at 2m resolution, and the subset editor was used to examine each field sheet and clean artifacts from biological targets and other unwanted soundings. Cleaned data were exported in ASCII xyz format and imported to ArcGIS where they were combined and exported to a single unfilled ESRI ASCII GRID. This is a raw 2m grid of sonar data and no further processing was done on this product.

Process_Date: 2009
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Coastal and Marine Geology Program
Contact_Person: David Finlayson
Contact_Address:
Address_Type: mailing and physical
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
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: C:\DOCUME~1\DAVIDF~1\LOCALS~1\Temp\xml7A.tmp
Process_Date: 20100407

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 17404
Column_Count: 24469
Vertical_Count: 1

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: 0.999600
Longitude_of_Central_Meridian: -123.000000
Latitude_of_Projection_Origin: 0.000000
False_Easting: 500000.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 2.000000
Ordinate_Resolution: 2.000000
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: D_WGS_1984
Ellipsoid_Name: WGS_1984
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257224

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: monterey_bay_STD_itrf2000_utm10
Entity_Type_Definition:
The standard deviation of the raw bathymetry grid is provided in ESRI ASCII GRID format in WGS84 (G1150). This represents the weighted standard deviation for all of the soundings used to compute the elevation of the grid cell. The standard deviation (2 sigma) where values are in meters.
Entity_Type_Definition_Source: USGS
Attribute:
Attribute_Label: ObjectID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Value
Attribute_Definition:
These are standard deviations of gridded data from swath sonar returns.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Unrepresentable_Domain: Standard Deviation values in meters (float)

Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Coastal and Marine Geology Program
Contact_Person: David Finlayson
Contact_Address:
Address_Type: mailing and physical address
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.

Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology.

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: ASC
Transfer_Size: 1635.635
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <https://pubs.usgs.gov/ds/514/>
Fees: none

Metadata_Reference_Information:
Metadata_Date: 20100504
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Coastal and Marine Geology Program
Contact_Person: David Finlayson
Contact_Address:
Address_Type: mailing and physical address
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
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile

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URL: https://pubs.usgs.gov/ds/514/
Maintained by: Mike Diggles
Page last modified and
Generated by mp version 2.9.8 on Tue May 4 14:13:30 2010