Rikk G. Kvitek
Carrie K. Bretz
Peter Dartnell
Sam Y. Johnson
Guy R. Cochrane
2013
Contours--Offshore of San Gregorio, California
Version 1.0, 2013
vector
Guy R. Cochrane
Peter Dartnell
H. Gary Greene
Janet T. Watt
Nadine E. Golden
Charles A. Endris
Eleyne L. Phillips
Stephen R. Hartwell
Samuel Y. Johnson
Rikk G. Kvitek
Mercedes D. Erdey
Carrie .K. Bretz
Michael W. Mansion
Ray W. Sliter
Stephanie L. Ross
Brian E. Dieter
John L. Chin
2014
California State Waters Map Series--Offshore of San Gregorio Map Area, California
map
Scientific Investigations Map
SIM 3306
Reston, VA
U.S. Geological Survey
https://dx.doi.org/10.3133/sim3306
https://pubs.usgs.gov/sim/3306/
Nadine E. Golden
2013
California State Waters Map Series Data Catalog
database
Data Series
DS 781
Reston, VA
U.S. Geological Survey
https://pubs.usgs.gov/ds/781/
This part of SIM 3306 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 7, 10, SIM 3306) of the Offshore of San Gregorio map area, California. The vector data file is included in "Contours_OffshoreSanGregorio.zip," which is accessible from https://pubs.usgs.gov/ds/781/OffshoreSanGregorio/data_catalog_OffshoreSanGregorio.html.
10-m interval contours of the Offshore of San Gregorio 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 intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposesThese data can be used with geographic information systems or other software to identify bathymetric features.
2006
2007
ground condition
As needed
-122.54
-122.34
37.39
37.23
Global Change Master Directory (GCMD)
Oceans > Bathymetry/SeafloorTopography > Bathymetry
Oceans > Bathymetry/SeafloorTopography > Seafloor Topography
General
Marine Geology
Multibeam
Contours
Bathymetry
Water Depth
Ocean Floor Topography
U.S. Geological Survey
USGS
Pacific Coastal and Marine Science Center
CMGP
ISO 19115 Topic Category
geoscientIficinformation
imageryBaseMapsEarthCover
oceans
Geographic Names Information System (GNIS)
San Gregorio
Half Moon Bay
State of California
None
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.
Peter Dartnell
U.S. Geological Survey,
Pacific Coastal and Marine Science Center
Physical Scientist
mailing and physical address
400 Natural Bridges Dr.
Santa Cruz
CA
95060-5792
USA
(831) 460-7415
(831) 427-4709
pdartnell@usgs.gov
<https://pubs.usgs.gov/ds/781/OffshoreSanGregorio/images/Contours_OffshoreSanGregorio.jpg>
Acoustic backscatter imagery of offshore San Gregorio.
GIF Offshore San Gregorio
Not applicable
Unspecified
Complete
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.
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.
During the mapping missions, an Applanix position and motion compensation system (POS/MV) was used to accurately position the vessel during data collection, and it also accounted for vessel motion such as heave, pitch, and roll (position accuracy, ±2 m; pitch, roll, and heading accuracy, ±0.02%, heave accuracy, ±5%, or 5 cm). KGPS altitude data (Fugro Pelagos, StarFix HP & XP units; CSUMB, NavCom 2050) were used to account for tide cycle fluctuations and sound velocity profiles were collected with an Applied Microsystems SVPlus sound velocimeter. Soundings were corrected for vessel motion using the Applanix POS/MV data, for variations in water-column sound velocity using the AM SVPlus data, and for variations in water height (tides) using vertical-position data from the KGPS receivers. Final XYZ soundings and bathymetric-surface models were referenced to the World Geodetic System of 1984 (WGS 1984) relative to the North American Vertical Datum of 1988 (NAVD 1988). 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.
2007
Carrie Bretz
Seafloor Mapping Lab, California State University Monterey Bay
Projects Manager, GIS & Metadata Supervisor
mailing and physical address
100 Campus Center, Bldg 13
Seaside
CA
93955
USA
831.582.4197
carrie_bretz@csumb.edu
Vector
String
6
WGS 1984 UTM Zone 10N
0.9996
-117.0
0.0
500000.0
0.0
coordinate pair
0.0001
0.0001
Meter
D WGS 1984
WGS 1984
6378137.0
298.257223563
Contours_OffshoreSanGregorio.shp
The shapefile attributes include FID - Internal Feature Number, SHAPE - feature geometry, VALUE - code for the seafloor character classes, ID - feature ID, and CONTOUR - contour depth value. The shapefile can be added to any ESRI ArcMap project.
ESRI
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
SHAPE
Feature geometry
ESRI
Polyline
ID
Unique identifier for each contour line. Value of 0 means the line segment has been generated during the smoothing process.
ESRI
-60
-10
Double
CONTOUR
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 -60 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.
USGS
-60
-10
Integer values -10 to -60 representing depth intervals as described above.
20130614
20130614
Peter Dartnell
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Physical Scientist
mailing and physical address
400 Natural Bridges Dr.
Santa Cruz
CA
95060-5792
USA
(831) 460-7415
(831) 427-4709
pdartnell@usgs.gov
Content Standard for Digital Geospatial Metadata
("CSDGM version 2")
FGDC-STD-001-1998
universal time