This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Half Moon map
area, California. The vector data file is included in "Contours_OffshoreHalfMoonBay.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshoreSanGregorio/data_catalog_OffshoreSanGregorio.html.
10-m interval contours of the Offshore of Half Moon Bay map area, California, were generated from bathymetry data collected
by Fugro Pelagos and by California State University, Monterey Bay, Seafloor Mapping Lab (CSUMB). Mapping was completed in
2006 and 2007, using a combination of 400-kHz Reson 7125 and 244-kHz Reson 8101 multibeam echosounders. These mapping missions
combined to collect bathymetry from about the 10-m isobath to beyond the 3-nautical-mile limit of California's State Waters.
Bathymetric contours at 10-m intervals were generated from the merged 2-m bathymetric surface. The most continuous contour
segments were preserved while smaller segments and isolated island polygons were excluded from the final output. Contours
were smoothed via a polynomial approximation with exponential kernel (PAEK) algorithm using a tolerance value of 60 m. The
contours were then clipped to the boundary of the map area. These data are not intended for navigational purposes.
Citation
Title Contours--Offshore of Half Moon Bay, California
These data are intended for science researchers, students, policy makers, and the general public. This information is not
intended for navigational purposes. These data can be used with geographic information systems or other software to identify
bathymetric features.
thumbnail file description:
Contours derived from bathymetry of offshore Half Moon Bay.
Resource language:
eng; USA
Resource progress code:
completed
Resource Maintenance Information
maintenance or update frequency:
asNeeded
Constraints on resource usage:
Constraints
Use limitation statement:
Constraints on resource usage:
Legal Constraints
use constraint:
otherRestrictions
Other constraints
Use Constraints: Please recognize the U.S. Geological Survey (USGS) and the California State University, Monterey Bay, Seafloor
Mapping Lab (CSUMB). USGS-authored or produced data and information are in the public domain. 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.
Constraints on resource usage:
Legal Constraints
Access Constraints
otherRestrictions
Other constraints
Access Constraints: None
Spatial representation type code:
vector
Resource extent
Geographic Extent
Geographic Bounding Box
westBoundLongitude
-122.58
eastBoundLongitude
-122.42
northBoundLatitude
37.55
southBoundLatitude
37.39
Temporal Extent
2006-01-01
2007-01-01
point of contact
-
pointOfContact
individual Name Peter Dartnell
organisation Name
U.S. Geological Survey, Pacific Coastal and Marine Science Center
position Name Physical Scientist
Contact information
Telephone
Voice (831) 460-7415
Fax (831) 427-4709
Address
400 Natural Bridges Dr., Santa Cruz, CA, 95060-5792
Country USA
descriptor Unique identifier for each contour line. Value of 0 means the line segment has been generated during the smoothing process.
sequence Identifier
name ID
Long Wavelength
-10
Short Wavelength
-50
units
Band
descriptor Contours are lines that connect points of equal depth based on the bathymetry grid. The contour values indicate the depth
value the line represents. This makes it easier to identifier features on the seafloor. Contour lines were generated at 10-m
intervals, from -10 m to -50 m, then the contours were clipped to the boundary of the map area. Values are negative to indicate
depth below sea level. The value of 0 represents a line segment created during the smoothing process.
name Of Measure Horizontal Positional Accuracy Report
evaluation Method Description
Estimated to be no less than 2 m, owing to water depth and total propagated uncertainties of the mapping systems, which include
sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning,
gridding, and datum transformations.
AbsoluteExternalPositionalAccuracy
name Of Measure Vertical Positional Accuracy Report
evaluation Method Description
Estimated to be no less than 20 cm, owing to water depth and total propagated uncertainties of the mapping systems, which
include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding
cleaning, gridding, and datum transformations.
notes: This metadata was automatically generated from the Content Standard for Digital Geospatial Metadata ("CSDGM version 2") standard
(version FGDC-STD-001-1998) using the 2012-06-20T17:21:00 version of the FGDC RSE to ISO 19115-2 transform.
notes: Last Metadata Review Date: 2014-08-25
Metadata contact
-
pointOfContact
individual Name Peter Dartnell
organisation Name
U.S. Geological Survey, Pacific Coastal and Marine Science Center
position Name Physical Scientist
Contact information
Telephone
Voice (831) 460-7415
Fax (831) 427-4709
Address
400 Natural Bridges Dr., Santa Cruz, CA, 95060-5792
Country USA