Long Island Sound Environmental Studies

Metadata:

* Identification_Information
* Data_Quality_Information
* Spatial_Data_Organization_Information
* Spatial_Reference_Information
* Entity_and_Attribute_Information
* Distribution_Information
* Metadata_Reference_Information

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Identification_Information:

Description:

Abstract: This CD-ROM (Compact Disk - Read Only Memory) contains sidescan sonar, high-resolution seismic-reflection, bathymetric, textural, and bibliographic data and interpretations collected, compiled, and produced through the U.S. Geological Survey/State of Connecticut Cooperative and the Long Island Sound Environmental Studies Project of the Coastal and Marine Geology Program, U.S. Geological Survey during October 1991 to August 1998. Cooperative research with the State of Connecticut was initiated in 1982. During the initial phase of this cooperative program, geologic framework studies in Long Island Sound were completed. The second and current phase of the program, which is the focus of this CD-ROM, emphasizes studies of sediment distribution, processes that control sediment distribution, near-shore environmental concerns, and the relationship of benthic communities to sea-floor geology. The study area covers all of Long Island Sound, which is bordered on the north by the rocky shoreline of Connecticut, on the east by Block Island Sound, on the south by the eroding sandy bluffs of Long Island, and on the west by the East River and the New York metropolitan area.

Sidescan sonar data were variously collected with 100 kHz Klein, Datasonics, and Edgetech systems under two survey schemes. In the first scheme, the data were collected along closely-spaced grids where the ship tracks were spaced 150 m apart and the sonar system was set to sweep 100 m to either side of the ship's track. This scheme produced the continuous-coverage acoustic images that are stored on the CD-ROM as TIF files. In the second scheme, the sidescan sonar data collected along reconnaissance lines spaced about 2,400 m apart. Only selected portions of this data, when used for geologic interpretation, are stored on this CD-ROM. Under both survey schemes, the sidescan sonar data were processed according to procedures summarized by Danforth and others (1991) and Paskevich (1992a, 1992b, 1992c).

The seismic reflection data were variously collected with an Ocean Research Equipment 3.5-kHz profiler transmitting at a 0.25-s repetition rate and a Datasonics CHIRP system set to sweep between 2-7 kHz. Only selected seismic-reflection data, which are used as examples in geologic interpretations, are stored as GIF-formatted images on this CD-ROM.

Navigation during this project was determined with a differential Global Positioning System (GPS); position data were logged at 10-second intervals. The bathymetric data were collected by means of a 200-kHz echo sounder and logged digitally.

Surficial sediment (0-2 cm below the sediment-water interface) sampling completed as part of this project was conducted using a Van Veen grab sampler equipped with an Osprey video and still camera system. The photographic system was used to appraise bottom variability around stations, faunal communities, and sedimentary processes. It also documented bedrock outcrops and boulder fields where samples could not be collected. The fine fraction (less than 62 microns) was analyzed by Coulter Counter (Shideler, 1976); the coarse fraction was analyzed by sieving (gravel) and by rapid sediment analyzer (sand; Schlee, 1966). The data were corrected for the salt content of interstitial water. Size classifications are based on the method proposed by Wentworth (1929) and were calculated using the inclusive graphics statistical method (Folk, 1974), using the nomenclature proposed by Shepard (1954). A detailed discussion of the sedimentological methods employed are given in Poppe and others (1985); a detailed description of the methods used to perform the CHN analyses are given in Poppe and others (1996) . The database presented here contains over 14,000 records and 83 fields (see the Data Dictionary below). The specific fields and parameters have been chosen based on the data produced by the sedimentation laboratory of the Coastal and Marine Geology Program of the U.S. Geological Survey in Woods Hole, Mass., and the format of information typically found in the literature. Because the data have come from numerous sources, there are differing amounts and types of information. Most of the samples or sets of samples do not have data in all of the given fields. However, additional fields, qualifiers, and data can be added in virtually unlimited fashion to accommodate specific needs. The database itself is provided in four formats: Microsoft EXCEL, ver. 5, Quattro Pro for Windows, Dbase IV, and Tab-delimited ASCII text.

Four bathymetric data sets are presented and include:1) Interpretations of the bathymetry within the continuous-coverage sidescan sonar study areas; 2} The NOS database modified to remove extraneous data (i.e. bouys); 3) Contoured National Ocean Service (NOS) bathymetry digitized by Applied Geographics Inc., Boston, Massachusetts; and 4) a fly-by based on the modified NOS database. Data files are present in ASCII format with navigation and depth in meters. The bathymetric interpretations within the sidescan sonar study areas are based on mean sea level and stored as TIF images; the NOS data are based on mean low sea level; and the fly-by is configured to run in QuickTime or MPEG, which can be downloaded from this CD-ROM.

The bibliographic database, which contains over 2,000 references, is stored as an ASCII text, Microsoft Word, Corel WordPerfect, HTML, and Microsoft EXCEL files. This bibliography is largely a compilation of references from Lewis and Coffin (1985) and the GENCAT bibliographic database at the Long Island Sound Resource Center, Connecticut Department of Environmental Protection, Groton, Connecticut. These sources have been supplemented by citations from the BIOSIS, GEOREF, and FISH AND FISHERIES WORLDWIDE bibliographic databases.

Purpose: Long Island Sound is a major east-coast estuary that has more than 8 million people within its watershed. Because of this enormous population, anthropogenic wastes, toxic chemicals, and changes in land use from residential, commercial, and recreational development have stressed the environment of the Sound, causing degradation and potential loss of benthic habitats (Koppelman and others, 1976). A detailed understanding of sea-floor processes are needed to help evaluate the extent of adverse impacts and to manage resources wisely in the future. Therefore, we conducted acoustic and sampling surveys, both regionally and within specific areas of special interest. The data and interpretations serve many purposes including: (1) defining the geological variability of the sea floor, one of the primary controls of benthic habitat diversity; (2) improving our understanding of the processes that control the distribution and transport of bottom sediments, the benthic habitats, and the associated infaunal community structures; and (3) providing raw data and a detailed framework for future research, monitoring, and management activities. The sidescan-sonar mosaics also serve as base maps for subsequent sedimentological, geochemical and biological observations because precise information on environmental setting is important for selection of sampling sites and for accurate interpretation of point measurements. The goal of this project is to provide a regional synthesis of the offshore geology and physical oceanography to support a wide variety of management decisions and to provide a basis for further process-oriented investigations. The project was conducted cooperatively with the Connecticut Department of Environmental Protection Connecticut Geologic and Natural History Survey, the University of New Haven, the University of Connecticut, and the New York State Department Division of Coastal Resources..

Entity_and_Attribute_Detail_Citation:

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 19911001

Beginning_Time:

Ending_Date: 19981001

Ending_Time:

Currentness_Reference: publication date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -73.8

East_Bounding_Coordinate: -71.8

North_Bounding_Coordinate: 41.4

South_Bounding_Coordinate: 40.75

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: sidescan sonar

Theme_Keyword: sediment texture

Theme_Keyword: bathymetry

Theme_Keyword: bibliograpgy

Theme_Keyword: ISO 9660 CD-ROM

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: Long Island Sound

Place_Keyword: Connecticut

Place_Keyword: New York

Place_Keyword: CT

Place_Keyword: NY

Place_Keyword: estuary

Access_Constraints: none

Use_Constraints: none

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Lawrence J. Poppe

Contact_Organization: U.S. Geological Survey

Contact_Position: Long Island Sound Environmental Studies Project

Contact_Address:

Address_Type: mailing address

Address:

U.S. Geological Survey

Woods Hole Field Center

384 Woods Hole Road

Quissett Campus

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-2314

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: lpoppe@usgs.gov

Data_Set_Credit: Long Island Sound Environmental Studies Project

Native_Data_Set_Environment: sidescan sonar: 8-mm tape; 3.5 kHz high-resolution seismic reflection: analog records; bathymetry and navigation: 3.5" diskettes; bottom video: 8-mm tapes; databases are housed on both PCs and UNIX systems.

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Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:

Attribute_Accuracy_Explanation:

Logical_Consistency_Report:

Completeness_Report: archive of acoustic (sidescan and bathymetric) and sampling (textural) data

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report: The ships were navigated with Differential GPS

Quantitative_Horizontal_Positional_Accuracy_Assessment:

Horizontal_Positional_Accuracy_Value: 5-10 meters

Horizontal_Positional_Accuracy_Explanation: DGPS is assumed to be accurate within 5-10 meters

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report: Bathymetry was corrected to mean sea-level by the Tidal Analysis Branch of the national Oceanographic and Atmospheric Administration and commercially available software.

Quantitative_Vertical_Positional_Accuracy_Assessment:

Vertical_Positional_Accuracy_Value: 1 m

Vertical_Positional_Accuracy_Explanation: All depths were rounded to the nearest meter.

Lineage:

Process_Step:

Process_Description: The sidescan sonar data were logged on 8-mm tape with the Q-MIPS and ISIS acquisition systems. The Norwalk and Milford surveys were processed the U.S. National Marine Fisheries facility in Milford, Connecticut. All other processing of sidescan data were performed at the Woods Hole Field Center of the Coastal and Marine Geology Program, U.S. Geological Survey. The sediment samples were frozen in the field. Textural samples were processed in the sedimentation laboratory at the Woods Hole Field center; CHN analyses were performed at the facilities of the Woods Hole Oceanographic Institution and the Marine Biological Laboratory. Mean sea-level tidal-height measurements used to correct the bathymetric data for the detailed surveys were computed by the Tidal Analysis Branch of the National Oceanographic and Atmospheric Administration, Silver Spring, Maryland (Norwalk, Milford, Hammonasset, Niantic Bay, and Fishers Island Sound Surveys) and Tides and Currents version 2.1, a commercially available software program (Falkner Island, Roanoke Point, New Haven harbor, and new haven Dumping Ground Surveys) .

Source_Used_Citation_Abbreviation:

Process_Date: 199709

Source_Produced_Citation_Abbreviation:

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Poppe, Lawrence J.

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing address

Address:

U.S. Geological Survey

Woods Hole Field Center

384 Woods Hole Road

Quissett Campus

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 457-2314

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address:

lpoppe@usgs.gov

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Spatial_Data_Organization_Information:

Indirect_Spatial_Reference: Horizontal X and Y are in decimal degrees from Greenwich and the Equator for each sample location. Navigation are stored with each record.

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Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name:

Geographic

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Planar_Distance_Units: Degrees decimal minutes

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:(for the subbottom data)

Altitude_Datum_Name: two-way travel time

Altitude_Resolution: 1

Altitude_Distance_Units: m

Altitude_Encoding_Method: Attribute values

Depth_System_Definition:

Depth_Datum_Name: mean sea level

Depth_Resolution: 1

Depth_Distance_Units: meters

Depth_Encoding_Method: Attribute values

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Entity_and_Attribute_Information:

Overview_Description:

Entity_and_Attribute_Overview: The sidescan sonar data were acquired using a Klein (Norwalk, Milford, Hammonasset, Niantic Bay, and Fishers Island Sound Surveys), Datasonics SIS-1000 (Falkner Island and Roanoke Point Surveys), and Edgetech (New Haven Harbor and New Haven Dumping Ground Surveys) sidescan sonar systems. The sidescan sonar data were digitally logged to 8-mm tape with Q-MIPS (Norwalk, Milford, Hammonasset, Niantic Bay, and Fishers Island Sound Surveys) and ISIS (Falkner Island, Roanoke Point, New Haven Harbor, and New Haven Dumping Ground Surveys) acquisition systems.The sidescan sonar data were processed according to procedures summarized by Danforth and others (1991) and Paskevich (1992a; 1992b). Briefly, the sonar data were multiplexed, filtered to convert the data into a processing format and to remove speckle noise and corrected for slant-range distortions. Additional corrections were applied to compensate for signal attenuation and dropped lines in the sonar data. A contrast enhancement based on the dynamic range of the data was applied, ship navigation was merged with the sonar data, and the data were geographically oriented and displayed on a Mercator grid.

After this preliminary processing, these data were used to make the composite digital mosaics. Alternating strips of sonar data were placed in their proper geographic location at the appropriate scale and projection (Paskevich (1992c). The adjacent sonar images were matched for tone, unwanted data (where two images overlapped) were digitally trimmed off, and images were progressively combined into composite digital images. Registration between the shiptrack navigation and the strips of sidescan sonar data are generally good throughout both of the study areas. The final digital mosaics, which have a 1-m pixel size, were output as TIF images for this CD-ROM.

Entity_and_Attribute_Detail_Citation:

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Distribution_Information:

Distributor:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Soderberg, Nancy

Contact_Organization: U.S. Geological Survey

Contact_Position: Data Library

Contact_Address:

Address_Type: mailing address

Address:

U.S. Geological Survey

Woods Hole Field Center

384 Woods Hole Road

Quissett Campus

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

Contact_Electronic_Mail_Address: nsoderberg@usgs.gov

Resource_Description: U.S. Geological Survey CD-ROM Open-File Report

Data Archive

Distribution_Liability: This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Although all data published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ISO 9660 CD-ROM

Format_Version_Number: ISO 9660

Format_Specification:

Format_Information_Content: TIF and JPEG images

File_Decompression_Technique: none

Transfer_Size: 650 MB

Digital_Transfer_Option:

Offline_Option:

Offline_Media: CD-ROM

Recording_Format: ISO 9660

Compatibility_Information: UNIX, DOS, MAC

Fees:

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Metadata_Reference_Information:

Metadata_Date: 19980801

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Polloni, Chris

Contact_Organization: U.S. Geological Survey

Contact_Position: Seafloor Mapping Group

Contact_Address:

Address_Type: mailing address

Address:

U.S. Geological Survey

Woods Hole Field Center

384 Woods Hole Road

Quissett Campus

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 457-2280

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: cpolloni@usgs.gov

Metadata_Standard_Name: FGDC Content Standard

Metadata_Standard_Version: 19940608

Metadata_Time_Convention: universal time

Metadata_Access_Constraints: none

Metadata_Use_Constraints: none

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