Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Larger_Work_Citation:
Citation_Information:
Originator: Larry Poppe
Originator: Ralph S. Lewis
Originator: Jane F. Denny
Originator: Mary L. DiGiacomo-Cohen
Originator: Kenneth F. Parolski
Publication_Date: 1999
Title:
Sidescan sonar image, surficial geologic interpretation, and bathymetry of the Long Island Sound sea floor around Falkner Island, Connecticut
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: Geologic Investigations Series Map
Issue_Identification: I-2671
Publication_Information:
Publication_Place: Woods Hole, MA
Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Description:
Abstract:
Because of the enormous surrounding population of
Long Island Sound, large inputs of anthropogenic
wastes (e.g. fertilizers and sewage) and toxic
chemicals have produced stresses on the environment
of the Sound, causing degradation and potential loss
of benthic habitats. Anthropogenic wastes, toxic
chemicals, and changes in land use patterns from
residential, commercial, and recreational development
have stressed the environment of the Sound causing
degradation and potential loss of benthic habitats.
These studies build upon cooperative research with
the State of Connecticut that was initiated in 1982.
This particular study covers the sea floor around
Falkner Island.
The Connecticut Coastal National Wildlife Refuge
is part of the National Wildlife Refuge System. This
system constitutes an array of federal lands overseen
by the U.S. Fish and Wildlife Service that are set
aside primarily for the benefit of wildlife, for
managing biodiversity, and for the protection of
unique ecosystems. The refuge is made up of Milford
Chimon and Sheffield Islands
off Norwalk, Ram Island at the mouth of the Mystic
River, and Falkner Island.
Falkner Island's inaccessibility has allowed it to
remain relatively undeveloped and to become a refuge
for rare and environmentally sensitive fauna and
flora that have been unable to survive elsewhere
along the mainland coast. For example, the island
is Connecticut's only significant habitat for Roseate
Terns and the nesting area for 80 percent of
Connecticut's population of Common Terns.
Purpose:
This dataset presents the completed sidescan sonar
mosaic for Falkner Island, Connecticut study area
Supplemental_Information:
Distinctive acoustic patterns revealed by this
the complex patches of high and low
backscatter that coincide with areas where the
glacial drift crops out (boulders and bedrock),
elongate patches of alternating high and low
backscatter (sand waves), areas of lower backscatter
(dark, finer grained sediment), and areas of high
backscatter (light, coarser grained sediment). The
numerous ship wakes present on the image attest to
the popularity of sport falknerhing in the vicinity of
Falkner Island.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19960615
Ending_Date: 19960616
Currentness_Reference: Ground Condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -072.682872
East_Bounding_Coordinate: -072.632872
North_Bounding_Coordinate: +41.233431
South_Bounding_Coordinate: +41.191764
Keywords:
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: USGS
Theme_Keyword: U.S. Geological Survey
Theme_Keyword: Coastal and Marine Geology Program
Theme_Keyword: Long Island Sound Research Center
Theme_Keyword: Connecticut Geological and Natural History Survey
Theme_Keyword: sidescan sonar
Theme_Keyword: estuary
Theme_Keyword: benthic habitat
Theme_Keyword: hypoxia
Theme_Keyword: sediment distribution
Theme_Keyword: benthic community
Theme_Keyword: surficial geology
Theme_Keyword: Connecticut Coastal National Wildlife Refuge
Theme_Keyword: National Wildlife Refuge System
Theme_Keyword: U.S. Fish and Wildlife Service
Place:
Place_Keyword_Thesaurus: General
Place_Keyword: Long Island Sound
Place_Keyword: Connecticut
Place_Keyword: Falkner Island
Place_Keyword: estuary
Place_Keyword: Eastern Long Island Sound
Access_Constraints: None
Use_Constraints:
The U.S. Geological Survey must be referenced as the
originator of the dataset in any future products or
research derived from these data.
Although this derived data set and it's lineage dataset
have been used by the USGS, no warrant, expressed
or implied, is made by the USGS as to the accuracy
of the data and/or related materials. The act of
distribution shall not constitute any such warranty,
and no responsibility is assumed by the USGS in the use
of these data or related materials.
SIS-1000 Datasonics sidescan sonar system set to
image 100-m to either side of the shiptrack. These
data were logged digitally to 8-mm tape on a ISIS
data acquisition system.
Type_of_Source_Media: cartridge tape
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19960615
Ending_Date: 19960616
Source_Currentness_Reference: Ground Condition
Source_Citation_Abbreviation: QMIPS
Source_Contribution:
These data were processed to apply radiometric and
geometric corrections. The processed swaths were
then mapped and digitally mosaicked to complete
the sidescan sonar mosaic for the study area.
Process_Step:
Process_Description:
QMIPS data were processed through a median
filtering routine to suppress speckle noise.
Navigation merged into the header record portion
of the data were plotted and checked. The QMIPS
data were exported for import to the WHIPS
processing.
Source_Used_Citation_Abbreviation: QMIPS
Process_Date: Unknown
Source_Produced_Citation_Abbreviation: WHIPS
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02532-1598
Country: USA
Contact_Voice_Telephone: (508) 548-8700 x2311
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Process_Step:
Process_Description:
The individual sidescan swaths were processed
to apply a slant-to-ground range correction,
shading correction and striped noise removal.
the geometrically and radiometrically enhanced
swaths were then individually mapped to a user
specified scale and projection.
Source_Used_Citation_Abbreviation: WHIPS
Process_Date: Unknown
Source_Produced_Citation_Abbreviation: WHIPS
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02532-1598
Country: USA
Contact_Voice_Telephone: (508) 548-8700 x2311
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Process_Step:
Process_Description:
The individually mapped swaths were imported
into a PCI "pix" database file for digital
mosaicking. The mosaicking procedure included
trimming off unwanted data where two sonar images
overlapped, tone matching the adjacent sonar
images if there are differences, and combining
the individual strips together into a
composite image.
Utilizing the PCI Remote Sensing Software
reprojection utility, the completed and
archived mosaic was reprojected to UTM to
be consistent with current Long Island
Sound GIS datasets.
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: WGS84
Semi-major_Axis: 6378137.00
Denominator_of_Flattening_Ratio: 0.00335281066747
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: (508) 548-8700
Contact_Facsimile_Telephone: (508) 457-2310
Resource_Description: falkner Island sidescan sonar mosaic: GEOTIFF image.
Distribution_Liability:
Although this derived data set and it's lineage
dataset have been used by the USGS, no warranty,
expressed or implied, is made by the USGS as to
the accuracy of the data and/or related materials.
The act of distribution shall not constitute any such
warranty, and no responsibility is assumed by the USGS
in the use of these data or related materials.
The sidescan sonar mosaic is available as a
GEOTIFF image with accompanying world file and
georeference report. To utilize this data, the user
must have an image viewer, image processing or
GIS software package capable of importing a
GEOTIFF image. If the georeferencing information
cannot be imported, the user may wish to obtain
the georeference information contained in a separate
file, georep.txt, included in the zip file.
