U.S. Geological Survey
2009
MOSAIC7 - Composite sidescan-sonar mosaic collected by the U.S. Geological Survey offshore of the Chandeleur Islands, LA, 2007 (UTM Zone 16N GeoTIFF)
1.0
remote-sensing image
Open-File Report
2008-1195
Woods Hole Coastal and Marine Science Center, Woods Hole, MA
U.S. Geological Survey, Coastal and Marine Geology Program
https://doi.org/10.3133/ofr20081195
http://pubs.usgs.gov/of/2008/1195/GIS_catalog/Sidescan/mosaic7.zip
Wayne E. Baldwin
Elizabeth A. Pendleton
David C. Twichell
2009
Geophysical Data from offshore of the Chandeleur Islands, Eastern Mississippi Delta
1.0
Open-File Report
2008-1195
Reston, VA
U.S. Geological Survey
http://pubs.usgs.gov/of/2008/1195/
In 2006 and 2007, the U.S. Geological Survey, in partnership with Louisiana Department of Natural Resources and the University of New Orleans, conducted geologic mapping to characterize the sea floor and shallow subsurface stratigraphy offshore of the Chandeleur Islands in Eastern Louisiana. The mapping was carried out during two cruises on the R/V Acadiana. Data were acquired with the following equipment: an SEA Ltd SwathPlus interferometric sonar (234 kHz), Klein 3000 dual frequency sidescan sonar, and an Edgetech 512i chirp subbottom profiling system. The long-term goal of this mapping effort is to produce high-quality geologic maps and geophysical interpretations that can be utilized to investigate the impact of Hurricane Katrina in 2005 and to identify sand resources within the region.
This GeoTIFF (Tagged Image File Format) contains approximately 71 square-km of sidescan sonar data that were collected in 2007. These data are used to define the sea-floor morphology offshore of the Chandeleur Islands in Eastern Louisiana.
20070612
20070621
ground condition
None planned
-89.085591
-88.928501
29.589904
29.466703
USGS Metadata Identifier
USGS:4e5b05a5-14c6-4ff3-b9eb-7ab0e318335f
None
U.S. Geological Survey
USGS
Woods Hole Science Center
WHSC
Coastal and Marine Geology Program
CMGP
sidescan-sonar
sidescan
side scan sonar
backscatter
GeoTIFF image
grey scale
composite image
WHSC field activity report number 07007
mosaic
ISO 19115 Topic Category
oceans
geoscientificInformation
imageryBaseMapsEarthCover
USGS Thesaurus
sea-floor acoustic reflectivity
image mosaics
sidescan sonar
marine geophysics
geospatial datasets
None
Louisiana
Chandeleur Islands
Breton Island
Gosier Island
Curlew Island
MRGO
New Harbor Islands
North Islands
North-Central Gulf Coast
United States
Gulf of Mexico
Mississippi River Gulf Outlet
None
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
David C. Twichell
U.S. Geological Survey
Geologist
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
508-548-8700 x2266
508-457-2310
dtwichell@usgs.gov
http://pubs.usgs.gov/of/2008/1195/images/mosaic7.jpg
grey scale image of sidescan-sonar mosaic
JPEG
Microsoft Windows XP Professional x64 Edition Version 2003 Service Pack 2; ESRI ArcCatalog 9.2.4.1420
W.W. Danforth
T.F. O'Brien
W.C. Schwab
1991
USGS image processing system: near real-time mosaicking of high-resolution sidescan-sonar data
Sea Technology
Jan. 1991
William W. Danforth
1997
XSonar/ShowImage: A complete system for rapid sidescan-sonar processing and display.
Open-File Report
97-686
Reston, VA
U.S. Geological Survey
https://pubs.er.usgs.gov/publication/ofr97686
A. Malinverno
M. Edwards
W.B.F. Ryan
1990
Processing of SeaMARC swath sonar data.
Journal of Oceanic Engineering
15
V.F. Paskevich
1996
MAPIT: An improved method for mapping digital sidescan sonar data using the Woods Hole Image Processing System (WHIPS) Software
Open-File Report
96-281
Reston, VA
U.S. Geological Survey
https://pubs.er.usgs.gov/publication/ofr96281
Information unavailable from original metadata.
All available data were used to create the backscatter mosaic. Some lines with excess noise were clipped after the mosaic was completed.
These data were navigated with a Differential Global Positioning System (DGPS) mounted above the interferometric sonar head. Unless noted, all DGPS data are referenced to WGS84. The layback distance between towed sidescan sonar fish and the mounted GPS antennae were measured on the ship and corrected for these navigation data.
10
The differential GPS is accurate within 1 to 2 meters. The layback of the towfish adds additional uncertainty due to changes in angle and scope of the tow cable in response to sea state and vessel speed. Original metadata specified the horizontal positional accuracy value as < 10 meters.
U.S. Geological Survey
Unpublished material
Sidescan-sonar data collection
disc
20070612
20070621
ground condition
raw sidescan data
Data acquisition at sea:
These sidescan-sonar data were collected with a Klein 3000 dual frequency sidescan sonar towed 3 meters astern of the R/V Acadiana. These data were acquired using SonarPro Software (version: none) during a cruise in June 2007. Data were collected along tracklines spaced 100 to 125 m apart at a speed of 1.5 to 2.5 m/s. The dual frequencies of the sonar system are 100 and 500 kHz . Navigation was by means of differential GPS. All sidescan-sonar data were logged digitally at a sample rate resulting in a 0.18-m pixel size in the across-track direction and approximately 0.14-m in the along-track direction following the methodology outlined in Danforth and others (1991) and Danforth (1997).
Within XSonar Software (version: none) a median filtering routine (Malinverno and others, 1990) was applied to the raw sidescan-sonar data (.xtf) to remove speckle noise; the filter was 6 pixels across track by 3 pixels along track. The data were further processed to correct for fish altitude, slant and beam artifacts, and then merged with the navigation (Danforth, 1997). These 2007 data were affected by port noise on the following days 20070610-20070619. XSonar was edited to reduce the port highpass value (from 4095 to 2500), in an effort to improve the sonar image. Odd and even sidescan sonar lines were mapped seperately out of XSonar at 1 meter/pixel resolution. Sidescan areas were defined within the cruise domain such that the sonar images mapped in XSonar would be no larger than 200 Mb.
2007
Elizabeth A. Pendleton
U.S. Geological Survey
Geologist
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700x2259
(508) 457-2310
ependleton@usgs.gov
The odd and even area files were imported into PCI Geomatica Software (version 10.1) to be digitally mosaicked together using PCI's OrthoEngine and procedures described in Paskevich (1996). The mosaicking process produces an enhanced, geographically correct, sidescan-sonar mosaic with 1 meter/pixel resolution. The composite mosaic was exported as a GeoTIFF image.
MOSAIC9.pix
2007
MOSAIC9.tif
Elizabeth A. Pendleton
U.S. Geological Survey
Geologist
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700x2259
(508) 457-2310
ependleton@usgs.gov
The days that experienced portside noise problems (20070610-20070619) needed further processing to improve the mosaic image. Portside swaths that displayed as 'whiteout' within the mosaicked image had pixel values greater than 200 (out of 256) due to noise, and were deleted using the lasso tool in Adobe Photoshop CS2 (version 9.0.2).
Unknown
Elizabeth A. Pendleton
U.S. Geological Survey
Geologsit
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700x2259
(508) 457-2310
ependleton@usgs.gov
Edits to the metadata were made to fix any errors that MP v 2.9.34 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). The source information was incomplete and had to be modified to meet the standard. Formatting of the cross-references was fixed to meet the metadata standard. Some online links were added to the cross-references. The distribution format name was modified in an attempt to be more consistent with other metadata files of the same data format. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent.
20161103
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
USGS Thesaurus keywords added to the keyword section.
20180720
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
Crossref DOI link was added as the first link in the metadata.
20191118
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
Added keywords section with USGS persistent identifier as theme keyword.
20200908
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
Raster
Pixel
13400
15000
1
Universal Transverse Mercator
16
0.999600
-87.000000
0.000000
500000.000000
0.000000
row and column
1.000000
1.000000
meters
D_WGS_1984
WGS_1984
6378137.000000
298.257224
There are no attributes associated with a GeoTIFF image. Image pixel values contain acoustic reflectivity values normalized to an 8-bit data range (0-255). Low-backscatter is represented by dark tones (low values) and high-backscatter is represented by bright tones (high values). The background color is set to 255 and can be turned off without removing data values.
U.S. Geological Survey
Wayne E. Baldwin
U.S. Geological Survey
Geologist
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700x2226
(508) 457-2310
wbaldwin@usgs.gov
Downloadable Data
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
GeoTIFF
PCI version 10.1
This WinZip (version 9.0) file contains a geographic GeoTIFF image of side-scan sonar data collected offshore of the Chandeleur Islands, LA, and associated metadata.
use WinZip or pkUnzip
37.9
http://pubs.usgs.gov/of/2008/1195/GIS_catalog/Sidescan/mosaic7.zip
Data can be downloaded via the World Wide Web (WWW)
DVD-ROM
4.75
Gbytes
UDF
none
This zip file contains a GeoTIFF image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image.
20240318
Elizabeth A. Pendleton
U.S. Geological Survey
Geologist
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700x2259
(508) 457-2310
whsc_data_contact@usgs.gov
The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240318)
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
None
None