Carrie K. Bretz
Rikk G. Kvitek
Peter Dartnell
Mercedes D. Erdey
2015
BackscatterB [7125]--Offshore Pigeon Point, California
1.0
GeoTiff
Data Series
DS 781
Reston, VA
U.S. Geological Survey
https://www.sciencebase.gov/catalog/item/5548073be4b0a658d7954cf6
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/
https://cmgds.marine.usgs.gov/data/csmp/OffshorePigeonPoint/data_catalog_OffshorePigeonPoint.html
This part of DS 781 presents data for the acoustic-backscatter map of Offshore of Pigeon Point map area, California. Backscatter data are provided as three separate grids depending on mapping system. This metadata file refers to the data included in "BackscatterB_7125_OffshorePigeonPoint.zip," which is accessible from https://doi.org/10.5066/F7513W80. These data accompany the pamphlet and map sheets of Cochrane, G.R., Watt, J.T., Dartnell, P., Greene, H.G., Erdey, M.D., Dieter, B.E., Golden, N.E., Johnson, S.Y., Endris, C.A., Hartwell, S.R., Kvitek, R.G., Davenport, C.W., Krigsman, L.M., Ritchie, A.C., Sliter, R.W., Finlayson, D.P., and Maier, K.L. (G.R. Cochrane and S.A. Cochran, eds.), 2015, California State Waters Map Series—Offshore of Pigeon Point, California: U.S. Geological Survey Open-File Report 2015–1232, pamphlet 40 p., 10 sheets, scale 1:24,000, https://doi.org/10.3133/ofr20151232.
The acoustic-backscatter map of the Offshore of Pigeon Point, California was generated from backscatter data collected by California State University, Monterey Bay (CSUMB), by Fugro Pelagos, and by the U.S. Geological Survey (USGS). Mapping was completed between 2006 and 2009, using a combination of 400-kHz Reson 7125 and 244-kHz Reson 8101 multibeam echosounders, as well as a 234-kHz SWATHplus bathymetric sidescan-sonar system. Within the final imagery, brighter tones indicate higher backscatter intensity, and darker tones indicate lower backscatter intensity. The intensity represents a complex interaction between the acoustic pulse and the seafloor, as well as characteristics within the shallow subsurface, providing a general indication of seafloor texture and composition. Backscatter intensity depends on the acoustic source level; the frequency used to image the seafloor; the grazing angle; the composition and character of the seafloor, including grain size, water content, bulk density, and seafloor roughness; and some biological cover. Harder and rougher bottom types such as rocky outcrops or coarse sediment typically return stronger intensities (high backscatter, lighter tones), whereas softer bottom types such as fine sediment return weaker intensities (low backscatter, darker tones).
These data are intended for science researchers, students, policy makers, and the general public. These data can be used with geographic information systems or other software.
Any use of trade, product, or firm 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 Esri format, this metadata file may include some Esri-specific terminology.
2006
2009
ground condition
As needed
-122.49
-122.29
37.23
37.07
USGS Metadata Identifier
USGS:5548073be4b0a658d7954cf6
Global Change Master Directory (GCMD)
Acoustic Reflectivity
None
Fisheries
Backscatter
Intensity
Seafloor Character
U.S. Geological Survey
USGS
Coastal and Marine Hazards and Resources Program
CMHRP
Pacific Coastal and Marine Science Center
PCMSC
ISO 19115 Topic Category
geoscientificInformation
environment
oceans
imageryBaseMapsEarthCover
Data Categories for Marine Planning
distributions
physical habitats and geomorphology
Marine Realms Information Bank (MRIB) keywords
seabed
sidescan sonar
marine geophysics
USGS Thesaurus
geology
bathymetry
ecosystems
multibeam sonar
sonar methods
sidescan sonar
image mosaics
marine geophysics
sea-floor characteristics
sea-floor acoustic reflectivity
maps and atlases
geospatial datasets
Coastal and Marine Ecological Classification Standard (CMECS)
Marine Nearshore Subtidal
Marine Offshore Subtidal
Transform Continental Margin
Continental/Island Shelf
Rock Substrate
Unconsolidated Mineral Substrate
Geographic Names Information System (GNIS)
Pacific Ocean
State of California
Pigeon Point
San Mateo County
Ano Nuevo
Coastal and Marine Ecological Classification Standard (CMECS)
Northern California Ecoregion
Coastal and Marine Ecological Classification Standard (CMECS)
Substrate
None
USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey and California State University Monterey Bay as the originator(s) of the dataset and in products derived from these data.
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060-5792
US
831-427-4747
pcmsc_data@usgs.gov
https://www.sciencebase.gov/catalog/file/get/5547e66ae4b0a658d79520c0?name=BackscatterB_7125_OffshorePigeonPoint.jpg&allowOpen=true
Acoustic backscatter imagery of offshore Pigeon Point.
JPEG
Microsoft Windows Server 2008 R2 Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 10.0
Guy R. Cochrane
Janet T. Watt
Peter Dartnell
H. Gary Greene
Mercedes D. Erdey
Bryan E. Dieter
Nadine E. Golden
Samuel Y. Johnson
Charles A. Endris
Stephen R. Hartwell
Rikk G. Kvitek
Clifton W. Davenport
Lisa M. Krigsman
Andrew C. Ritchie
Ray W. Sliter
David P. Finlayson
Katherine L. Maier
2015
California State Waters Map Series--Offshore of Pigeon Point, California
map
Open-File Report
2015-1232
Reston, VA
U.S. Geological Survey
https://doi.org/10.3133/ofr20151232
Not applicable for raster data.
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.
Not applicable to acoustic-backscatter imagery.
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 degrees; heave accuracy, +/-5 percent, 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. Processing and mosaicking of Reson 7125 trace data were completed using GEOCODER Version 3.2 level 1 (created by Luciano Fonseca; Fugro Pelagos Modified Test Release 16). Within Geocoder, the backscatter intensities were radiometrically corrected (including despeckling and angle varying gain adjustments) and the position of each acoustic sample was geometrically corrected for slant-range and georeferenced to UTM Zone 10 N, WGS1984 datum. After the lines were imported, they were mosaicked into a 1m resolution image. Overlap between parallel lines was resolved using a priority table based on the distance of each sample from the ship track, with samples closest to- and furthest from- the ship track given the lowest priority. An anti-aliasing algorithm was also applied.
2006
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
California Seafloor Mapping Project 1- and 2-m resolution backscatter imagery (CSMP survey blocks CC-09, CC-10, and CC-11) within this map were downloaded from California State University, Monterey Bay, Seafloor Mapping Lab (http://seafloor.csumb.edu/SFMLwebDATA.htm) and converted to grids. Backscatter grids of similar mapping systems were merged in a GIS and clipped to the boundary of the map area. Grids from different mapping systems were not merged together due to different mapping frequencies and processing techniques.
2014
Pete 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
pdartnell@usgs.gov
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
20171005
U.S. Geological Survey
Alan O. Allwardt
Contractor -- Information Specialist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
831-460-7551
831-427-4748
aallwardt@usgs.gov
Added keywords from Coastal and Marine Ecological Classification Standard (CMECS) to metadata.
20180426
U.S. Geological Survey
Alan O. Allwardt
Contractor -- Information Specialist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
831-460-7551
831-427-4748
aallwardt@usgs.gov
Corrected author spelling in Larger Work section
20180622
Susan A Cochran
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Geologist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060-5792
USA
(831) 460-7545
scochran@usgs.gov
Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.
20201019
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Edits were made to bring the metadata up to current PCMSC standards including standardizing authors' names, adding a doi# link, correcting typos, refining keywords, and using current access and distribution liability statements. Point of Contact and Metadata Contact information sections were changed to static PCMSC contact information. No data were changed. The metadata available from a harvester may supersede metadata bundled within a download file. Users are advised to compare the metadata date of this file to any similar file to ensure they are using the most recent version.
20211101
U.S. Geological Survey
Susan A. Cochran
Geologist
Mailing and Physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-7545
scochran@usgs.gov
Raster
Grid Cell
8890
8890
1
Universal Transverse Mercator
10
0.9996
-123.00000
0.00000
500000.0
0.00
coordinate pair
2.0
2.0
Meters
WGS84
WGS84
6378137.00
298.257223563
Value
BackscatterB [7125] intensity value
ESRI
Rowid
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
VALUE
Backscatter intensity values
ESRI
0.0
253.0
Integers representing intensity values
COUNT
The number of pixels (2m x 2m size grid cell) represented in each intensity value (see Attribute: VALUE).
ESRI
18
176981
Integers
The merged Reson 8101 acoustic-backscatter grid was originally archived as an ESRI grid
with the following attributes:
>Cell size = 2.0
>Number of rows = 8885
>Number of columns = 8880
>
>Data type = floating point
>
>Boundary
>Xmin = 545630
>Xmax = 563390
>Ymin = 4103330
>Ymax = 4121100
>
>Statistics
>Minimum value = 0
>Maximum value = 254
>Mean = 157.75
>Standard deviation = 29.38
>
>Coordinate system description
>Projection UTM
>Zone 10
>Datum WGS84
>Units meter
none
U.S. Geological Survey
mailing and physical address
345 Middlefield Rd
Menlo Park
CA
94025-3561
USA
(650) 329-4309
The .zip file (BackscatterB_7125_OffshorePigeonPoint.zip) includes the .tfw, .tif, .tif.aux.xml, and .tif.ovr files, as well as FGDC-compliant metadata for the BackscatterB [7125] data layer in the Offshore Pigeon Point region of California.
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
TIFF
ArcMap (version 10.0, ESRI, 2011)
Raster data layer is registered TIFF image in the UTM Zone 10 coordinate system with datum WGS84.
The .zip file for the TIFF image includes the image (.tif), the world registration file (.tfw), and the text (.txt) and XML (.tif.xml) versions of the metadata for the BackscatterB [7125] data layer of Offshore Pigeon Point, California.
WinZip
12.6
https://www.sciencebase.gov/catalog/file/get/5548073be4b0a658d7954cf6
https://cmgds.marine.usgs.gov/data/csmp/OffshorePigeonPoint/data_catalog_OffshorePigeonPoint.html
https://doi.org/10.3133/ds781
The first link will begin a direct download of the data. The second link is a landing page on which all of the downloadable data for a particular region are listed. The third link is a landing page for the entire data catalog.
none
The downloadable data file has been compressed with the "zip" command and can be unzipped with Winzip (or other tool) on Windows systems. To utilize these data, the user must have software capable of uncompressing the WinZip file and importing and viewing an Esri ArcMap TIFF. Users should download the ArcGIS Project File, OffshorePigeonPointGIS.mxd.zip, a compressed (with the "zip" command) version of the ArcMap document (.mxd) that has all the data layers loaded in the table of contents for "Offshore Pigeon Point" and has all the data symbolized as on the data release map sheets. Download and save this ArcGIS project file, including all data layers, to the directory the user has created for this GIS.
20211101
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060-5792
US
831-427-4747
pcmsc_data@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time