Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA (simplified point shapefile and CSV files)

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What does this data set describe?

Title:
Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA (simplified point shapefile and CSV files)
Abstract:
Two marine geological surveys were conducted in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey (USGS), University of Connecticut, and University of New Haven through the Long Island Sound Mapping and Research Collaborative. Sea-floor images and videos were collected at 210 sampling sites within the survey area, and surficial sediment samples were collected at 179 of the sites. The sediment data and the observations from the images and videos are used to identify sediment texture and sea-floor habitats.
Supplemental_Information:
See the larger work citation to view the geotagged sea-floor images, location of bottom images, sea-floor videos, and location of bottom video tracklines collected during the surveys. For more information about these field activities, see https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-056-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-018-FA. These data were collected as part of a larger collaborative project, the Long Island Sound Habitat Mapping Initiative; for more information about this project, see https://lismap.uconn.edu/.
  1. How might this data set be cited?
    U.S. Geological Survey, 20201123, Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA (simplified point shapefile and CSV files): data release DOI:10.5066/P9GK29NM, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts.

    Online Links:

    This is part of the following larger work.

    Ackerman, Seth D., Huntley, Emily C., Blackwood, Dann S., Babb, Ivar G., Zajac, Roman N., Conroy, Christian W., Auster, Peter J., Schneeberger, Courtney L., and Walton, Olivia L., 2020, Sea-floor sediment and imagery data collected in Long Island Sound, Connecticut and New York, 2017 and 2018: data release DOI:10.5066/P9GK29NM, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Ackerman, S.D., Huntley, E.C., Blackwood, D.S., Babb, I.G., Zajac, R.N., Conroy, C.W., Auster, P.J., Schneeberger, C.L., and Walton, O.L., 2020, Sea-floor sediment and imagery data collected in Long Island Sound, Connecticut and New York, 2017 and 2018: U.S. Geological Survey data release, https://doi.org/10.5066/P9GK29NM.
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -72.430178
    East_Bounding_Coordinate: -71.866860
    North_Bounding_Coordinate: 41.324710
    South_Bounding_Coordinate: 41.193178
  3. What does it look like?
    https://www.sciencebase.gov/catalog/file/get/5de9be03e4b02caea0eeda45/?name=2017-056-FA_and_2018-018-FA_samples_browse.jpg (JPEG)
    Map of sediment sample locations in the survey area in Long Island Sound, Connecticut and New York.
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 28-Nov-2017
    Ending_Date: 15-May-2018
    Currentness_Reference:
    Data were collected on the following dates: 20171128-20171203 and 20180508-20180515
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: vector and tabular digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • Entity point (210)
    2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.00000001. Longitudes are given to the nearest 0.00000001. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_WGS_1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257224.
  7. How does the data set describe geographic features?
    2017-056-FA_and_2018-018-FA_samples_GS-LD
    Grain-size analysis results using the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction for sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 during USGS field activities 2017-056-FA and 2018-018-FA. (Source: U.S. Geological Survey)
    ANALYSIS_ID
    An identifier for the sample that is unique to the database. This identifier begins with the assigned multi-letter code GS-, which corresponds to the type of analysis performed on the sample (grain-size analysis), followed by a six-digit number assigned sequentially as samples are registered for analysis. (Source: U.S. Geological Survey) Character string.
    SAMPLE_ID
    The identification value assigned to the sample at the time of collection. This varies from field activity to field activity, and the ID can contain any combination of letters and numbers. (Source: U.S. Geological Survey) Character string.
    PROJECT
    Name of project or project number under which samples were taken or data generated; sometimes project name indicates a more specific area. (Source: U.S. Geological Survey) Character sting.
    FAN
    The serial number assigned to the dataset field activity during which the sample was collected. This value is in the format YYYY-XXX-FA where YYYY is the year, XXX is the number assigned to the activity within the year, and FA indicates Field Activity. (Source: U.S. Geological Survey) Character string.
    SUBMITTER
    Name of Principal investigator or chief scientist responsible for data collection, or researcher submitting samples for analysis (usually first initial and last name). (Source: U.S. Geological Survey) Character string.
    AREA
    General geographic area of data collection. Name is general enough to easily locate area on a map. (Source: U.S. Geological Survey) Character string.
    SUBMISSION
    Unique sample submission identifier. This identifier begins with the initials of the submitter, followed by a two-digit number assigned sequentially relative to previous submissions. (Source: U.S. Geological Survey) Character string.
    LATITUDE
    Latitude coordinate, in decimal degrees (WGS 84), of sample location. South latitude is recorded as negative values. (Source: U.S. Geological Survey)
    Range of values
    Minimum:41.19317830
    Maximum:41.32471000
    Units:decimal degrees
    Resolution:0.00000001
    LONGITUDE
    Longitude coordinate, in decimal degrees (WGS 84), of sample location. West longitude is recorded as negative values. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-72.43017830
    Maximum:-71.86686000
    Units:decimal degrees
    Resolution:0.00000001
    DEPTH_M
    Approximate depth of water in meters at the sample location derived from an unpublished composite bathymetry dataset used by the Long Island Sound Mapping and Research Collaborative project. (Source: U.S. Geological Survey)
    Range of values
    Minimum:4
    Maximum:89
    Units:meters
    Resolution:1
    T_DEPTH
    Top depth of the sample below the sediment-water interface in centimeters. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:centimeters
    B_DEPTH
    Bottom depth of the sample below the sediment-water interface in centimeters. (Source: U.S. Geological Survey)
    Range of values
    Minimum:2
    Maximum:2
    Units:centimeters
    DEVICE
    Sampling device used to collect the sample. (Source: U.S. Geological Survey) Character string.
    DATE COLLECTED
    Calendar date based on UTC time indicating when the sample was collected in the format MM/DD/YYYY where MM is the numeric month, DD is the day of the month, and YYYY is the year. (Source: U.S. Geological Survey) Character string.
    ANALYSIS COMPLETION DATE
    Calendar date indicating when analyses on the sample were completed in the format MM/DD/YYYY where MM is the numeric month, DD is the day of the month, and YYYY is the year. (Source: U.S. Geological Survey) Character string.
    ANALYSIS METHOD
    Method used to analyze the sample for grain-size distribution. (Source: U.S. Geological Survey)
    ValueDefinition
    GS-LDGrain-size analysis using the HORIBA laser diffraction unit and sieving of the >= -2 phi fraction.
    WEIGHT WET SAMPLE (g)
    Weight of initial sample in grams. (Source: U.S. Geological Survey)
    Range of values
    Minimum:4.3286
    Maximum:30.3185
    Units:grams
    Resolution:0.0001
    GRAVEL (wt%)
    Gravel content in percent dry weight of the sample. Gravel consists of particles with nominal diameters greater than 2 mm (-1 phi and larger). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:61.3508
    Units:weight percent
    Resolution:0.0001
    SAND (wt%)
    Sand content in percent dry weight of the sample. Sand consists of particles with nominal diameters less than 2 mm, but greater than or equal to 0.0625 mm (0 phi through 4 phi, inclusive). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.0515
    Maximum:99.5135
    Units:weight percent
    Resolution:0.0001
    SILT (wt%)
    Silt content in percent dry weight of the sample. Silt consists of particles with nominal diameters less than 0.0625 mm, but greater than or equal to 0.004 mm (5 phi through 8 phi, inclusive). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:62.8030
    Units:weight percent
    Resolution:0.0001
    CLAY (wt%)
    Clay content in percent dry weight of the sample. Clay consists of particles with nominal diameters less than 0.004 mm (9 phi and smaller). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:47.5030
    Units:weight percent
    Resolution:0.0001
    CLASSIFICATION (Shepard)
    Sediment classification based on a rigorous definition (Shepard [1954] as modified by Schlee and Webster [1967], Schlee [1973], and Poppe and others [2005]). In the definitions below, gravel is defined as particles with nominal diameters greater than 2 mm; sand consists of particles with nominal diameters less than 2 mm, but greater than or equal to 0.0625 mm; silt consists of particles with nominal diameters less than 0.0625 mm, but greater than or equal to 0.004 mm; and clay consists of particles with nominal diameters less than 0.004 mm. (Source: U.S. Geological Survey)
    ValueDefinition
    clayey siltSediment whose main phase is silt, but with significant clay.
    gravelSediment whose main phase is gravel.
    gravelly sedimentSediment whose main phase is gravel, but with significant other sediment. Gravel greater than 10 percent.
    sandSediment whose main phase is sand.
    sandy siltSediment whose main phase is silt, but with significant sand.
    silty sandSediment whose main phase in sand, but with significant silt.
    MEAN (Method of Moments Statistics - Logarithmic [phi])
    Average value in the grain-size distribution in phi units. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-2.16
    Maximum:8.59
    Units:phi
    Resolution:0.01
    STDEV (Method of Moments Statistics - Logarithmic [phi])
    Standard deviation (root mean square of the deviations) of the grain-size distribution in phi units (sorting). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.57
    Maximum:3.87
    Units:phi
    Resolution:0.01
    SKEWNESS (Method of Moments Statistics - Logarithmic [phi])
    Skewness (deviation from symmetrical form) of the grain-size distribution in phi units. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-2.39
    Maximum:4.29
    Units:phi
    Resolution:0.01
    KURTOSIS (Method of Moments Statistics - Logarithmic [phi])
    Kurtosis (degree of curvature near the mode) of the grain-size distribution in phi units. (Source: U.S. Geological Survey)
    Range of values
    Minimum:1.01
    Maximum:35.39
    Units:phi
    Resolution:0.01
    D10 (Method of Moments Statistics - Logarithmic [phi])
    Diameter at which 10% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-4.80
    Maximum:5.81
    Units:phi
    Resolution:0.01
    D25 (Method of Moments Statistics - Logarithmic [phi])
    Diameter at which 25% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-4.50
    Maximum:6.66
    Units:phi
    Resolution:0.01
    MEDIAN (D50; Method of Moments Statistics - Logarithmic [phi])
    Diameter at which 50% of the sample mass is comprised of sediment particles with a diameter less than this value and 50% is larger; middle point in the grain-size distribution in phi units. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-3.98
    Maximum:7.88
    Units:phi
    Resolution:0.01
    D75 (Method of Moments Statistics - Logarithmic [phi])
    Diameter at which 75% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.32
    Maximum:11.17
    Units:phi
    Resolution:0.01
    D90 (Method of Moments Statistics - Logarithmic [phi])
    Diameter at which 90% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.83
    Maximum:11.89
    Units:phi
    Resolution:0.01
    MEAN (Method of Moments Statistics - Arithmetic [micron])
    Average value in the grain-size distribution in microns. (Source: U.S. Geological Survey)
    Range of values
    Minimum:6.65
    Maximum:12,594.95
    Units:microns
    Resolution:0.01
    STDEV (Method of Moments Statistics - Arithmetic [micron])
    Standard deviation (root mean square of the deviations) of the grain-size distribution in microns (sorting). (Source: U.S. Geological Survey)
    Range of values
    Minimum:8.11
    Maximum:10,397.25
    Units:microns
    Resolution:0.01
    SKEWNESS (Method of Moments Statistics - Arithmetic [micron])
    Skewness (deviation from symmetrical form) of the grain-size distribution in microns. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-0.19
    Maximum:14.80
    Units:microns
    Resolution:0.01
    KURTOSIS (Method of Moments Statistics - Arithmetic [micron])
    Kurtosis (degree of curvature near the mode) of the grain-size distribution in microns. (Source: U.S. Geological Survey)
    Range of values
    Minimum:1.06
    Maximum:266.87
    Units:microns
    Resolution:0.01
    D10 (Method of Moments Statistics - Arithmetic [micron])
    Diameter at which 10% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.28
    Maximum:711.50
    Units:microns
    Resolution:0.01
    D25 (Method of Moments Statistics - Arithmetic [micron])
    Diameter at which 25% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.45
    Maximum:924.32
    Units:microns
    Resolution:0.01
    MEDIAN (D50; Method of Moments Statistics - Arithmetic [micron])
    Diameter at which 50% of the sample mass is comprised of sediment particles with a diameter less than this value and 50% is larger; middle point in the grain-size distribution in microns. (Source: U.S. Geological Survey)
    Range of values
    Minimum:4.93
    Maximum:15,856.37
    Units:microns
    Resolution:0.01
    D75 (Method of Moments Statistics - Arithmetic [micron])
    Diameter at which 75% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:10.86
    Maximum:23,976.96
    Units:microns
    Resolution:0.01
    D90 (Method of Moments Statistics - Arithmetic [micron])
    Diameter at which 90% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)
    Range of values
    Minimum:19.02
    Maximum:28,790.78
    Units:microns
    Resolution:0.01
    PHI_16
    Weight percent of the sample in the 16-phi fraction and smaller (nominal diameter of particles less than 0.00003125 mm); colloid. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:weight percent
    Resolution:0.001
    PHI_15
    Weight percent of the sample in the 15-phi fraction (nominal diameter of particles greater than or equal to 0.00003125 mm, but less than 0.0000625 mm); colloid. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:weight percent
    Resolution:0.001
    PHI_14
    Weight percent of the sample in the 14-phi fraction (nominal diameter of particles greater than or equal to 0.0000625 mm, but less than 0.000125 mm); colloid. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0.491
    Units:weight percent
    Resolution:0.001
    PHI_13
    Weight percent of the sample in the 13-phi fraction (nominal diameter of particles greater than or equal to 0.000125 mm, but less than 0.00025 mm); fine clay. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:7.122
    Units:weight percent
    Resolution:0.001
    PHI_12
    Weight percent of the sample in the 12-phi fraction (nominal diameter of particles greater than or equal to 0.00025 mm, but less than 0.0005 mm); fine clay. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:20.865
    Units:weight percent
    Resolution:0.001
    PHI_11
    Weight percent of the sample in the 11-phi fraction (nominal diameter of particles greater than or equal to 0.0005 mm, but less than 0.001 mm); fine clay. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:5.917
    Units:weight percent
    Resolution:0.001
    PHI_10
    Weight percent of the sample in the 10-phi fraction (nominal diameter of particles greater than or equal to 0.001 mm, but less than 0.002 mm); medium clay. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:1.938
    Units:weight percent
    Resolution:0.001
    PHI_9
    Weight percent of the sample in the 9-phi fraction (nominal diameter of particles greater than or equal to 0.002 mm, but less than 0.004 mm); coarse clay. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:11.171
    Units:weight percent
    Resolution:0.001
    PHI_8
    Weight percent of the sample in the 8-phi fraction (nominal diameter of particles greater than or equal to 0.004 mm, but less than 0.008 mm); very fine silt. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:20.639
    Units:weight percent
    Resolution:0.001
    PHI_7
    Weight percent of the sample in the 7-phi fraction (nominal diameter of particles greater than or equal to 0.008 mm, but less than 0.016 mm); fine silt. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:25.934
    Units:weight percent
    Resolution:0.001
    PHI_6
    Weight percent of the sample in the 6-phi fraction (nominal diameter of particles greater than or equal to 0.016 mm, but less than 0.031 mm); medium silt. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:21.261
    Units:weight percent
    Resolution:0.001
    PHI_5
    Weight percent of the sample in the 5-phi fraction (nominal diameter of particles greater than or equal to 0.031 mm, but less than 0.0625 mm); coarse silt. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:34.783
    Units:weight percent
    Resolution:0.001
    PHI_4
    Weight percent of the sample in the 4-phi fraction (nominal diameters of particles greater than or equal to 0.0625 mm, but less than 0.125 mm); very fine sand. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:54.543
    Units:weight percent
    Resolution:0.001
    PHI_3
    Weight percent of the sample in the 3-phi fraction (nominal diameter of particles greater than or equal to 0.125 mm, but less than 0.25 mm); fine sand. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:52.024
    Units:weight percent
    Resolution:0.001
    PHI_2
    Weight percent of the sample in the 2-phi fraction (nominal diameter of particles greater than or equal to 0.25 mm, but less than 0.5 mm); medium sand. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:59.879
    Units:weight percent
    Resolution:0.001
    PHI_1
    Weight percent of the sample in the 1-phi fraction (nominal diameter of particles greater than or equal to 0.5 mm, but less than 1 mm); coarse sand. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:69.706
    Units:weight percent
    Resolution:0.001
    PHI_0
    Weight percent of the sample in the 0-phi fraction (nominal diameters of particles greater than or equal to 1 mm, but less than 2 mm); very coarse sand. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:63.764
    Units:weight percent
    Resolution:0.001
    PHI_-1
    Weight percent of the sample in the -1-phi fraction (nominal diameter of particles greater than or equal to 2 mm, but less than 4 mm); very fine pebbles (granules). (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:8.571
    Units:weight percent
    Resolution:0.001
    PHI_-2
    Weight percent of the sample in the -2-phi fraction (nominal diameter of particles greater than or equal to 4 mm, but less than 8 mm); fine pebbles. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:29.953
    Units:weight percent
    Resolution:0.001
    PHI_-3
    Weight percent of the sample in the -3-phi fraction (nominal diameter of particles greater than or equal to 8 mm, but less than 16 mm); medium pebbles. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:53.733
    Units:weight percent
    Resolution:0.001
    PHI_-4
    Weight percent of the sample in the -4-phi fraction (nominal diameter of particles greater than or equal to 16 mm, but less than 32 mm); coarse pebbles. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:49.856
    Units:weight percent
    Resolution:0.001
    PHI_-5
    Weight percent of the sample in the -5-phi fraction (nominal diameter of particles greater than or equal to 32 mm, but less than 64 mm); very coarse pebbles. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:weight percent
    Resolution:0.001
    PHI_-6
    Weight percent of the sample in the -6-phi fraction and larger (nominal diameter of particles greater than or equal to 64 mm); cobbles and boulders. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:weight percent
    Resolution:0.001
    ANALYST
    Name (usually first, middle, and last initials) of person who performed the grain-size or physical properties analysis. (Source: U.S. Geological Survey) Character string.
    QA/QC COMMENTS
    Relevant comments on analytical observations or anomalies that may affect the quality of the data. Entries with no comments are left blank. (Source: U.S. Geological Survey) Character string.
    COMMENTS
    Comments field with the USGS site number and University of Connecticut's Northeast Underwater Research, Technology and Education Center (NURTEC) site name for the spring 2018 survey. (Source: U.S. Geological Survey) Character string.
    2017-056-FA_and_2018-018-FA_samples_GS-MS
    Grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction for sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 during USGS field activities 2017-056-FA and 2018-018-FA. These are the attributes for the CSV file. The shapefile is a simplified version of the CSV file with fewer attribute fields and two additional software-generated attributes, FID and Shape. Please see the entity and attribute overview section for a description of the shapefile attributes. (Source: U.S. Geological Survey)
    ANALYSIS_ID
    An identifier for the sample that is unique to the database. This identifier begins with the assigned multi-letter code GS-, which corresponds to the type of analysis performed on the sample (grain-size analysis), followed by a six-digit number assigned sequentially as samples are registered for analysis. No data value is -9999. (Source: U.S. Geological Survey) Character string.
    FIELD_NO
    The identification value assigned to the sample at the time of collection. This varies from field activity to field activity, and the ID can contain any combination of letters and numbers. (Source: U.S. Geological Survey) Character string.
    PROJECT
    Name of project or project number under which samples were taken or data generated; sometimes project name indicates a more specific area. (Source: U.S. Geological Survey) Character sting.
    FA_ID
    The serial number assigned to the dataset field activity during which the sample was collected. This value is in the format YYYY-XXX-FA where YYYY is the year, XXX is the number assigned to the activity within the year, and FA indicates Field Activity. (Source: U.S. Geological Survey) Character string.
    CONTACT
    Name of Principal investigator or chief scientist responsible for data collection, or researcher submitting samples for analysis (usually first initial and last name). (Source: U.S. Geological Survey) Character string.
    AREA
    General geographic area of data collection. Name is general enough to easily locate area on a map. (Source: U.S. Geological Survey) Character string.
    LATITUDE
    Latitude coordinate, in decimal degrees (WGS 84), of sample location. South latitude is recorded as negative values. (Source: U.S. Geological Survey)
    Range of values
    Minimum:41.19317830
    Maximum:41.32471000
    Units:decimal degrees
    Resolution:0.00000001
    LONGITUDE
    Longitude coordinate, in decimal degrees (WGS 84), of sample location. West longitude is recorded as negative values. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-72.43017830
    Maximum:-71.86686000
    Units:decimal degrees
    Resolution:0.00000001
    DEPTH_M
    Approximate depth of water in meters at the sample location derived from an unpublished composite bathymetry dataset used by the Long Island Sound Mapping and Research Collaborative project. (Source: U.S. Geological Survey)
    Range of values
    Minimum:4
    Maximum:89
    Units:meters
    Resolution:1
    T_DEPTH
    Top depth of the sample below the sediment-water interface in centimeters. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    Units:centimeters
    B_DEPTH
    Bottom depth of the sample below the sediment-water interface in centimeters. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:2
    Maximum:2
    Units:centimeters
    DEVICE
    Sampling device used to collect the sample. (Source: U.S. Geological Survey) Character string.
    DATE_COLLECTED
    Calendar date based on UTC time indicating when the sample was collected in the format MM/DD/YYYY where MM is the numeric month, DD is the day of the month, and YYYY is the year. (Source: U.S. Geological Survey) Character string.
    ANALYSIS_COMPLETION_DATE
    Calendar date indicating when analyses on the sample were completed in the format MM/DD/YYYY where MM is the numeric month, DD is the day of the month, and YYYY is the year. No data value is -9999. (Source: U.S. Geological Survey) Character string.
    WEIGHT
    Weight of initial sample in grams. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:36.3872
    Maximum:153.7566
    Units:grams
    Resolution:0.0001
    GRAVEL_PCT
    Gravel content in percent dry weight of the sample. Gravel consists of particles with nominal diameters greater than 2 mm (-1 phi and larger). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:74.3715
    Units:weight percent
    Resolution:0.0001
    SAND_PCT
    Sand content in percent dry weight of the sample. Sand consists of particles with nominal diameters less than 2 mm, but greater than or equal to 0.0625 mm (0 phi through 4 phi, inclusive). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:12.8380
    Maximum:99.8050
    Units:weight percent
    Resolution:0.0001
    SILT_PCT
    Silt content in percent dry weight of the sample. Silt consists of particles with nominal diameters less than 0.0625 mm, but greater than or equal to 0.004 mm (5 phi through 8 phi, inclusive). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.0002
    Maximum:60.4170
    Units:weight percent
    Resolution:0.0001
    CLAY_PCT
    Clay content in percent dry weight of the sample. Clay consists of particles with nominal diameters less than 0.004 mm (9 phi and smaller). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:41.9248
    Units:weight percent
    Resolution:0.0001
    CLASSIFICATION (Shepard)
    Sediment classification based on a rigorous definition (Shepard [1954] as modified by Schlee and Webster [1967], Schlee [1973], and Poppe and others [2005]). In the definitions below, gravel is defined as particles with nominal diameters greater than 2 mm; sand consists of particles with nominal diameters less than 2 mm, but greater than or equal to 0.0625 mm; silt consists of particles with nominal diameters less than 0.0625 mm, but greater than or equal to 0.004 mm; and clay consists of particles with nominal diameters less than 0.004 mm. (Source: U.S. Geological Survey)
    ValueDefinition
    gravelSediment whose main phase is gravel.
    gravelly sedimentSediment whose main phase is gravel, but with significant other sediment. Gravel greater than 10 percent.
    sandSediment whose main phase is sand.
    sandy siltSediment whose main phase is silt, but with significant sand.
    silty claySediment whose main phase in clay, but with significant silt.
    silty sandSediment whose main phase in sand, but with significant silt.
    MEDIAN
    Diameter at which 50% of the sample mass is comprised of sediment particles with a diameter less than this value and 50% is larger; middle point in the grain-size distribution in phi units. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-4.22
    Maximum:6.51
    Units:phi
    Resolution:0.01
    MEAN
    Average value in the grain-size distribution in phi units. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-3.04
    Maximum:5.94
    Units:phi
    Resolution:0.01
    STDEV
    Standard deviation (root mean square of the deviations) of the grain-size distribution in phi units (sorting). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.52
    Maximum:4.15
    Units:phi
    Resolution:0.01
    SKEWNESS
    Skewness (deviation from symmetrical form) of the grain-size distribution in phi units. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-1.90
    Maximum:4.66
    Units:phi
    Resolution:0.01
    KURTOSIS
    Kurtosis (degree of curvature near the mode) of the grain-size distribution in phi units. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:1.35
    Maximum:63.48
    Units:phi
    Resolution:0.01
    PHI_11
    Weight percent of the sample in the 11-phi fraction and smaller (nominal diameter of particles less than 0.001 mm); fine clay. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:9.451
    Units:weight percent
    Resolution:0.001
    PHI_10
    Weight percent of the sample in the 10-phi fraction (nominal diameter of particles greater than or equal to 0.001 mm, but less than 0.002 mm); medium clay. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:21.003
    Units:weight percent
    Resolution:0.001
    PHI_9
    Weight percent of the sample in the 9-phi fraction (nominal diameter of particles greater than or equal to 0.002 mm, but less than 0.004 mm); coarse clay. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:13.526
    Units:weight percent
    Resolution:0.001
    PHI_8
    Weight percent of the sample in the 8-phi fraction (nominal diameter of particles greater than or equal to 0.004 mm, but less than 0.008 mm); very fine silt. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:11.599
    Units:weight percent
    Resolution:0.001
    PHI_7
    Weight percent of the sample in the 7-phi fraction (nominal diameter of particles greater than or equal to 0.008 mm, but less than 0.016 mm); fine silt. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:13.693
    Units:weight percent
    Resolution:0.001
    PHI_6
    Weight percent of the sample in the 6-phi fraction (nominal diameter of particles greater than or equal to 0.016 mm, but less than 0.031 mm); medium silt. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:19.248
    Units:weight percent
    Resolution:0.001
    PHI_5
    Weight percent of the sample in the 5-phi fraction (nominal diameter of particles greater than or equal to 0.031 mm, but less than 0.0625 mm); coarse silt. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:26.456
    Units:weight percent
    Resolution:0.001
    PHI_4
    Weight percent of the sample in the 4-phi fraction (nominal diameters of particles greater than or equal to 0.0625 mm, but less than 0.125 mm); very fine sand. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.031
    Maximum:78.656
    Units:weight percent
    Resolution:0.001
    PHI_3
    Weight percent of the sample in the 3-phi fraction (nominal diameter of particles greater than or equal to 0.125 mm, but less than 0.25 mm); fine sand. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.065
    Maximum:81.325
    Units:weight percent
    Resolution:0.001
    PHI_2
    Weight percent of the sample in the 2-phi fraction (nominal diameter of particles greater than or equal to 0.25 mm, but less than 0.5 mm); medium sand. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.392
    Maximum:90.072
    Units:weight percent
    Resolution:0.001
    PHI_1
    Weight percent of the sample in the 1-phi fraction (nominal diameter of particles greater than or equal to 0.5 mm, but less than 1 mm); coarse sand. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.188
    Maximum:75.003
    Units:weight percent
    Resolution:0.001
    PHI_0
    Weight percent of the sample in the 0-phi fraction (nominal diameters of particles greater than or equal to 1 mm, but less than 2 mm); very coarse sand. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0.026
    Maximum:42.523
    Units:weight percent
    Resolution:0.001
    PHI_-1
    Weight percent of the sample in the -1-phi fraction (nominal diameter of particles greater than or equal to 2 mm, but less than 4 mm); very fine pebbles (granules). No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:29.194
    Units:weight percent
    Resolution:0.001
    PHI_-2
    Weight percent of the sample in the -2-phi fraction (nominal diameter of particles greater than or equal to 4 mm, but less than 8 mm); fine pebbles. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:35.482
    Units:weight percent
    Resolution:0.001
    PHI_-3
    Weight percent of the sample in the -3-phi fraction (nominal diameter of particles greater than or equal to 8 mm, but less than 16 mm); medium pebbles. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:26.718
    Units:weight percent
    Resolution:0.001
    PHI_-4
    Weight percent of the sample in the -4-phi fraction (nominal diameter of particles greater than or equal to 16 mm, but less than 32 mm); coarse pebbles. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:30.900
    Units:weight percent
    Resolution:0.001
    PHI_-5
    Weight percent of the sample in the -5-phi fraction and larger (nominal diameter of particles greater than or equal to 32 mm); very coarse pebbles, cobbles, and boulders. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:46.452
    Units:weight percent
    Resolution:0.001
    ANALYST
    Name (usually first, middle, and last initials) of person who performed the grain-size or physical properties analysis. No data value is -9999. (Source: U.S. Geological Survey) Character string.
    COMMENTS
    Comments field with the USGS site number and University of Connecticut's Northeast Underwater Research, Technology and Education Center (NURTEC) site name for the spring 2018 survey. (Source: U.S. Geological Survey) Character string.
    Entity_and_Attribute_Overview:
    The shapefile is a simplified version of the CSV file of the Multisizer analysis results (2017-056-FA_and_2018-018-FA_samples_GS-MS.csv) with fewer attribute fields. Specifically, STDEV, SKEWNESS, KURTOSIS, and the individual phi measurements (e.g., PHI_11) were removed. The shapefile also has two additional attributes, FID and Shape, which have the following descriptions:
    Attribute: Attribute Label: FID Attribute Definition: Internal feature number. Attribute Definition Source: Esri Attribute Domain Values: Unrepresentable Domain: Sequential unique whole numbers that are automatically generated.
    Attribute: Attribute Label: Shape Attribute Definition: Feature geometry. Attribute Definition Source: Esri Attribute Domain Values: Unrepresentable Domain: Coordinates defining the features.
    All the other attributes in the shapefile have the same definitions as the CSV file attributes (see the detailed description section for the 2017-056-FA_and_2018-018-FA_samples_GS-MS entity for definitions of the CSV file attributes). Please note that some of the field names were truncated since a shapefile field name can only contain up to 10 characters. The following fields are included in the shapefile: FID, Shape, ANALYSIS_I (truncated field name for ANALYSIS_ID), FIELD_NO, PROJECT, FA_ID, CONTACT, AREA, LATITUDE, LONGITUDE, DEPTH_M, T_DEPTH, B_DEPTH, DEVICE, DATE_COLLE (truncated field name for DATE_COLLECTED), ANALYSIS_C (truncated field name for ANALYSIS_COMPLETION_DATE), WEIGHT, GRAVEL_PCT, SAND_PCT, SILT_PCT, CLAY_PCT, CLASSIFICA (truncated field name for CLASSIFICATION), MEDIAN, MEAN, ANALYST, and COMMENTS.
    Entity_and_Attribute_Detail_Citation: U.S. Geological Survey

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • U.S. Geological Survey
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    Seth Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2315 (voice)
    508-457-2310 (FAX)
    sackerman@usgs.gov

Why was the data set created?

This dataset provides access to the locations and grain-size analysis results of surficial sediments collected with a modified Van Veen grab sampler on the SEABed Observation and Sampling System (SEABOSS) aboard the Research Vessel (R/V) Connecticut during USGS field activities 2017-056-FA (November 28 to December 3, 2017) and 2018-018-FA (May 8 to 15, 2018). These data were collected to explore the nature of the sea floor and to characterize the seabed by identifying sediment texture. The sediments were analyzed using two different methods: the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction, and the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction. The HORIBA LA-960 laser diffraction analyzer is a new method for analyzing grain-size distribution at the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center. This dataset was analyzed using both methods so that the results could be compared. Results of the comparison are not included in this data release.

How was the data set created?

  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
    Date: 15-May-2018 (process 1 of 8)
    Step 1: Collected data.
    Two marine geological surveys were conducted in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018. The R/V Connecticut occupied one of the target sites and the SEABOSS was deployed off the vessel's A-frame on the stern of the ship. The SEABOSS was equipped with a modified Van Veen grab sampler, a Nikon D300 digital still camera with a Photosea strobe, two video cameras (one forward-looking so that a shipboard operator could monitor for proper tow depth and obstacles, and one downward-looking, a Kongsberg Simrad OE1365 in this setup, that overlapped with the field of view of the still camera) with a topside feed, a GoPro HERO4 Black camera recording backup video, and lights to illuminate the sea floor for video and photograph collection. The elements of this particular SEABOSS were held within a stainless-steel frame that measured 1.15 x 1.15 meters. The frame had a stabilizer fin that oriented the system as it drifted over the seabed. The winch operator lowered the SEABOSS until the sea floor was observed in the topside live video feed. For those sites that were primarily targeted for a sediment grab, the vessel and SEABOSS then drifted with wind and current for up to a few minutes to ensure a decent image with a clear view of the sea floor was acquired; for those sites that were targeted for both a video transect of the sea floor and a sediment grab, the vessel was navigated along a planned transect for up to an hour. A scientist monitored the real-time bottom video and acquired bottom photographs at points of interest by remotely triggering the Nikon camera shutter. Bottom video was also recorded during the drift from the downward-looking video camera. Then, at most sites the winch operator lowered the Van Veen grab sampler until it rested on the sea floor. When the system was raised, the Van Veen grab sampler closed and collected a sample as it was lifted off the sea floor. Times for the sampler retrieval, which would later be used to derive the sample locations, were manually recorded in the survey log when the sampler was lifted off the seabed. The sampler was recovered to the deck of the survey vessel where a subsample was taken for grain-size analysis at the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center. Sediment samples were only attempted in areas where collecting a sample would not damage the SEABOSS; therefore, no samples were collected in areas with a cobble, boulder, or rocky seabed, as identified in real time using the topside live video feed. Samples were also not attempted if the current was too strong, if the deployment was aborted due to the strobe malfunctioning, or if the grab sampler accidentally tripped earlier in the deployment. A total of 210 sites were occupied aboard the R/V Connecticut with the SEABOSS: 93 sites were occupied in fall 2017 during field activity 2017-056-FA, and 117 sites were occupied in spring 2018 during field activity 2018-018-FA. Sediment samples were collected at 179 of the 210 sites. Person who carried out this activity:
    Seth Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2315 (voice)
    508-457-2310 (FAX)
    sackerman@usgs.gov
    Data sources produced in this process:
    • Sediment samples
    • Survey logs
    Date: Sep-2018 (process 2 of 8)
    Step 2: Acquired and processed navigation.
    During the surveys, WAAS-enabled GPS navigation from a Garmin GPSMAP 76C receiver was logged through a DataBridge data logger and ArcMap GPS. The GPS was set to receive fixes at a 2-second interval in geographic coordinates (WGS 84). Dates and times were recorded in Coordinated Universal Time (UTC). Log files were saved for each Julian day in text format. An AWK script (parse_gprmc17056.awk for the fall 2017 log files and parse_gprmc18018.awk for the spring 2018 log files) was used to parse the GPRMC navigation string from the log files for each survey and create ASCII Comma Separated Values (CSV) text files. The output files were merged for each survey and then reformatted using an AWK script (nav_time_reformat.awk), creating a processed navigation CSV text file for each sampling survey. Person who carried out this activity:
    Seth Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2315 (voice)
    508-457-2310 (FAX)
    sackerman@usgs.gov
    Data sources produced in this process:
    • Processed DataBridge navigation files
    Date: Sep-2018 (process 3 of 8)
    Step 3: Assembled sample information for sediment laboratory.
    The sediment sample times (as recorded in the survey logs) were used to parse GPS positions for each sediment sample from the logged GPS data. Approximate depths for each sample were derived from an unpublished composite bathymetry dataset used by the Long Island Sound Mapping and Research Collaborative project. This information was then provided to the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center with the sample analysis request form for each survey. Person who carried out this activity:
    Seth Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2315 (voice)
    508-457-2310 (FAX)
    sackerman@usgs.gov
    Data sources used in this process:
    • Survey logs
    • Processed DataBridge navigation files
    • Unpublished composite bathymetry
    Data sources produced in this process:
    • Sediment sample locations CSV files
    Date: 01-Mar-2019 (process 4 of 8)
    Step 4: Analyzed sediment samples using the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction.
    The samples from each survey were analyzed in the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center using two different methods: the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction, and the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction. Separate subsamples were taken from each sample submitted to the sediment analysis laboratory for each method. For the sediments analyzed using the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction, the subsamples for grain-size analysis were assigned unique analysis identifiers (ANALYSIS_ID) and divided into batches of no more than 30 samples. Each batch was entered into a Microsoft Excel data entry spreadsheet (LD Worksheet Template_xxxx.xlsx, where xxxx is the identifier assigned to the sample submission) to record the initial and dried sample weights, as well as the sieved coarse fraction weights. Each batch was also entered into macro-enabled Microsoft Excel data entry spreadsheets (GrainSizeWorksheet_LD1-30_xxxx(batch_yy).xlsm or GrainSizeWorksheet_LD31-60_xxxx(batch_yy).xlsm, where xxxx is the identifier assigned to the sample submission, "LD1-30" and "LD31-60" refer to the pre-labeled and weighed glass laser diffraction vials in which the samples will be run, and "batch_yy" refers to the sample batch) to record the measurement data coming from the laser diffraction unit and incorporate the initial, dried, and sieved weights. About 10-15 grams of wet sediment were placed in a pre-weighed beaker and the gross weight was recorded. The sample was wet sieved through a 4 mm (No. 5) sieve. If there was any coarse fraction remaining in the sieve, the coarse material was oven dried at 100 degrees Celsius in a pre-weighed beaker, and weighed again when dry. This coarse fraction was dry sieved to determine the individual weights of the -2- to -5-phi fractions, and the weights were recorded in the data entry spreadsheet LD Worksheet Template_xxxx.xlsx. The fine fraction in water was collected in a pre-labeled and weighed glass laser diffraction vial. If there was any coarse fraction remaining in the sieve from wet sieving, this vial was also oven dried at 100 degrees Celsius and weighed when dry. If there was no coarse fraction remaining from wet sieving, the sample can proceed directly to processing for analyses by the HORIBA LA-960 laser diffraction unit. Fine fractions ready for analysis by the HORIBA laser diffraction unit were rehydrated with distilled water if they had been dry. Fifteen (15) ml of pre-mixed 40 g/l sodium hexametaphosphate [(NaPO3)6] were added to each sample. If the height of the fluid in the laser diffraction vial was less than 5 cm, more distilled water was added to raise the level to no more than 8 cm in the vial. The samples were gently stirred, covered, and allowed to soak for at least 1 hour (for samples that were not dried) or up to 24 hours (for samples that were dried). Soaked vials were placed into an ultrasonic bath and run for 10 minutes at a frequency of 37 Hz with a power level of 100. If the samples appeared to be fully disaggregated, they were placed into pre-determined autosampler locations and were run using the HORIBA LA-960 for Windows software to get the fine fraction grain-size distributions. The fine fraction distribution data were added to the appropriate data entry spreadsheets (GrainSizeWorksheet_LD1-30_xxxx(batch_yy).xlsm or GrainSizeWorksheet_LD31-60_xxxx(batch_yy).xlsm) for each survey. The spreadsheet for each survey was used to calculate a continuous phi class distribution from the original fractions. Person who carried out this activity:
    Brian Buczkowski
    U.S. Geological Survey
    Physical Scientist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2361 (voice)
    508-457-2310 (FAX)
    bbuczkowski@usgs.gov
    Data sources used in this process:
    • Sediment samples
    • Sediment sample locations CSV files
    Data sources produced in this process:
    • Sediment subsamples
    • Laser diffraction data entry spreadsheets
    Date: 18-Apr-2019 (process 5 of 8)
    Step 5: Analyzed sediment samples using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction.
    The subsamples for grain-size analysis using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction were assigned unique analysis identifiers (ANALYSIS_ID), and a macro-enabled Microsoft Excel data entry spreadsheet (GrainSizeWorksheet_xxxx.xlsm, where xxxx is the batch number assigned to the sample submission) was created for each survey to record the measurement data. About 50 grams of wet sediment were placed in a pre-weighed beaker, weighed, oven dried at 100 degrees Celsius, and reweighed to correct for salt. The dried sample was wet sieved through a 0.062 mm (No. 230) sieve. The coarse fraction remaining in the sieve was oven dried at 100 degrees Celsius (until completely dried) and weighed. The fine fraction in water was collected in a plastic Nalgene bottle and sealed with a screw lid (stored for no longer than one week). The coarse fraction was dry sieved to determine the individual weights of the 4- to -5-phi fractions, and the weights were recorded in the data entry spreadsheet. The fine fraction was run and combined using the 200-micron and 30-micron Coulter analyses using the Multisizer 3 software to get the fine fraction grain-size distribution for each survey. The fine fraction distribution data were added to the data entry spreadsheet for each survey. The spreadsheet for each survey was used to calculate a continuous phi class distribution from the original fractions. Person who carried out this activity:
    Allison Paquette
    U.S. Geological Survey
    Integrated Statistics contractor to the U.S. Geological Survey
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    Data sources used in this process:
    • Sediment subsamples
    • Sediment sample locations CSV files
    Data sources produced in this process:
    • Multisizer data entry spreadsheets
    Date: 18-Apr-2019 (process 6 of 8)
    Step 6: Calculated grain-size classification and statistical analyses.
    A continuous phi class distribution from the original fractions was transposed to the "results" tab in the macro-enabled Microsoft Excel data entry workbook (GrainSizeWorksheet_LD1-30_xxxx(batch_yy).xlsm or GrainSizeWorksheet_LD31-60_xxxx(batch_yy).xlsm for the laser diffraction results, where xxxx is the identifier assigned to the sample submission, "LD1-30" and "LD31-60" refer to the pre-labeled and weighed glass laser diffraction vials in which the samples were run, and "batch_yy" refers to the sample batch; or GrainSizeWorksheet_xxxx.xlsm for the Multisizer results, where xxxx is the identifier assigned to the sample submission) for each survey. Macros in the workbook ("GS_MoM_Arithmatic," "GS_statistics," and "sedimentname" for the laser diffraction results, and "GS_statistics" and "sedimentname" for the Multisizer results) were run to calculate grain-size classification and statistical analyses and finish processing the data. Sample, navigation, and field identifiers along with continuous phi class distribution data, grain-size classification, and statistical analysis results were copied and pasted into a final Microsoft Excel spreadsheet (xxxx_GS-LD_results.xlsx for the laser diffraction results and xxxx_GS-MS_results.xlsx for the Multisizer results, where xxxx is the batch number assigned to the sample submission) for each survey. The processed data were quality control checked and assigned a quality grade based on the examination of the analytical data. Processed data were released to the submitter and incorporated into the laboratory's database. All raw analytical data generated by the samples were archived in the sediment analysis laboratory. Person who carried out this activity:
    Brian Buczkowski
    U.S. Geological Survey
    Physical Scientist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2361 (voice)
    508-457-2310 (FAX)
    bbuczkowski@usgs.gov
    Data sources used in this process:
    • Laser diffraction data entry spreadsheets
    • Multisizer data entry spreadsheets
    Data sources produced in this process:
    • Final Microsoft Excel spreadsheets (SA10_GS-LD_results.xlsx, SA11_GS-LD_results.xlsx, SA10_GS-MS_results.xlsx, and SA11_GS-MS_results.xlsx)
    Date: Oct-2019 (process 7 of 8)
    Step 7: Created final sediment grain-size analysis results CSV files.
    For the laser diffraction results, the sediment grain-size analysis results spreadsheets for each survey were merged in Microsoft Excel 2016 for Mac and then edited to remove the quality grade and metric distribution fields and to format fields. The Microsoft Excel spreadsheet was then saved as a CSV file (2017-056-FA_and_2018-018-FA_samples_GS-LD.csv). For the Multisizer results, the sediment grain-size analysis results spreadsheets for each survey were merged in Microsoft Excel 2016 for Mac and then edited to remove some fields, format fields, add site locations for those sites where no sample was successfully collected, and add a no data value (-9999) to empty attributes as needed. The sites with no successful grab were located using the start time of the sampler retrieval from the survey logs; the sampler retrieval position was chosen as the sample location because the video clip is considered the sample in the absence of a physical sample. Some of these site locations from the survey logs did not intersect a bottom video trackline, so they were moved to the last navigation fix along the site's bottom video trackline. Finally, the Microsoft Excel spreadsheet was saved as a CSV file (2017-056-FA_and_2018-018-FA_samples_GS-MS.csv). This process step and the subsequent process step were performed by the same person, Emily Huntley. Person who carried out this activity:
    Emily Huntley
    U.S. Geological Survey
    Geographer/Database Specialist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    ehuntley@contractor.usgs.gov
    Data sources used in this process:
    • Final Microsoft Excel spreadsheets (SA10_GS-LD_results.xlsx, SA11_GS-LD_results.xlsx, SA10_GS-MS_results.xlsx, and SA11_GS-MS_results.xlsx)
    • Survey logs
    Data sources produced in this process:
    • Final sediment grain-size analysis results CSV files
    Date: Oct-2019 (process 8 of 8)
    Step 8: Created a simplified sediment grain-size analysis results shapefile from the Multisizer analysis.
    The CSV file of the sediment grain-size analysis results from the Multisizer analysis was copied and edited to create a simplified version of the CSV file with fewer attribute fields (specifically, STDEV, SKEWNESS, KURTOSIS, and the individual phi measurements [e.g., PHI_11] were removed). A shapefile was created using the simplified version of the CSV file in Esri ArcGIS (version 10.3.1), and XTools Pro (version 12.0) for Esri ArcGIS was used to modify some field parameters in the point shapefile (Table Operations - Table Restructure). Please note that this metadata file represents the CSV file; users should access the CSV file for the full sediment grain-size analysis results. Data sources used in this process:
    • Final sediment grain-size analysis results CSV file from Multisizer analysis
    Data sources produced in this process:
    • Final simplified sediment grain-size analysis results shapefile
  3. What similar or related data should the user be aware of?
    Shepard, F.P., 1954, Nomenclature based on sand-silt-clay ratios: Journal of Sedimentary Petrology v. 24, no. 3., p. 151-158.

    Schlee, J.S., and Webster, J., 1967, A computer program for grain-size data: Sedimentology v. 8, no. 1., p. 45-53.

    Schlee, J.S., 1973, Atlantic continental shelf and slope of the United States—sediment texture of the northeastern part: Professional Paper 529-L, U.S. Geological Survey, Reston, VA.

    Online Links:

    Poppe, L.J., McMullen, K.Y., Williams, S.J., and Paskevich, V.F., 2014, USGS east-coast sediment analysis: Procedures, database, and GIS data: Open-File Report 2005-1001, U.S. Geological Survey, Reston, VA.

    Online Links:

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    All attributes were evaluated during data processing as standard quality control to ensure attributes contain accurate and relevant information and values. Due to rounding, the sum of the aggregate class percentages (e.g., GRAVEL (wt%), GRAVEL_PCT, etc.) and the sum of the phi fraction percentages (e.g., PHI_11, PHI_10, etc.) may not always add up to exactly 100.000%.
  2. How accurate are the geographic locations?
    Navigation for field activities 2017-056-FA and 2018-018-FA used Wide Area Augmentation System (WAAS)-enabled GPS. The GPS was set to receive fixes at a 2-second interval in geographic coordinates (World Geodetic System of 1984 [WGS 84]). The recorded position of each sediment sample is the position of the GPS antenna on the survey vessel, located on the aft port side of the R/V Connecticut, not the location of the SEABOSS. The antenna was located approximately 5 meters from the SEABOSS deployment location in fall 2017 and 3 meters in spring 2018. No layback or offset was applied to the recorded position. In addition, the SEABOSS may drift away from the survey vessel when deployed to the sea floor. Based on the various sources of horizontal offsets, a conservative estimate of the horizontal accuracy of the sediment sample locations is 10 meters. The sites with no successful grab included in the Multisizer results are located along the bottom video trackline at the start of the SEABOSS retrieval. Some of these site locations did not originally intersect a bottom video trackline and were moved to the last navigation fix along the site's bottom video trackline.
  3. How accurate are the heights or depths?
    The depths recorded for each sample are approximate and were derived from an unpublished composite bathymetry dataset used by the Long Island Sound Mapping and Research Collaborative project.
  4. Where are the gaps in the data? What is missing?
    Physical sediment samples were collected at 179 of the 210 sites occupied during field activities 2017-056-FA and 2018-018-FA; however, locations for all 210 sites are included in the Multisizer analysis results (2017-056-FA_and_2018-018-FA_samples_GS-MS.csv and 2017-056-FA_and_2018-018-FA_samples_GS-MS.shp) with no data values (i.e., -9999) for those sites with no sediment sample analysis. Sediment samples were only attempted in areas where collecting a sample would not damage the SEABOSS; therefore, no samples were collected in areas with a cobble, boulder, or rocky seabed, as identified in real time using the topside live video feed. Samples were also not attempted if the current was too strong, if the deployment was aborted due to the strobe malfunctioning, or if the grab sampler accidentally tripped earlier in the deployment. Each deployment of the SEABOSS is generally considered a unique site; however, five sites (sites SB64_2, 2018-018-024, 2018-018-089, 2018-018-094, and 2018-018-104) had two separate deployments because a sediment grab was not successfully collected during the first deployment. The sediment sample locations for these five sites are from the second deployment when a grab sample was successfully collected. For the spring 2018 data, 14 samples were randomly selected and run as replicates using the laser diffraction analyzer for internal testing purposes. The replicate results are not included in this publication.
  5. How consistent are the relationships among the observations, including topology?
    The sediment samples were all collected with the same modified Van Veen grab sampler mounted on the SEABOSS. The sediment samples were usually collected at the end of the video trackline, but some samples were collected in the middle of the transect (sites NB30, SB50_3, NB65, SB65_2, and 2018-018-112). The samples were analyzed using two methods; separate subsamples were taken for each grain-size analysis. For the spring 2018 survey, the University of Connecticut's Northeast Underwater Research, Technology and Education Center (NURTEC) assigned different names to the sites, which are available in the comments field (COMMENTS). Some USGS site numbers (FIELD_NO) have the same NURTEC site name (e.g., sites 2018-018-011 and 2018-018-012 are both NURTEC site NB64-T) because the NURTEC site names are based on the target sampling site names.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints: None
Use_Constraints:
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.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey - ScienceBase
    Denver Federal Center, Building 810, Mail Stop 302
    Denver, CO
    USA

    1-888-275-8747 (voice)
    sciencebase@usgs.gov
  2. What's the catalog number I need to order this data set? Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA. This dataset contains the following files: a CSV file of the sediment sample locations and grain-size analysis results using the HORIBA LA-960 laser diffraction analyzer and sieving of the >= -2-phi fraction (2017-056-FA_and_2018-018-FA_samples_GS-LD.csv); a CSV file of the sediment sample locations and grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction (2017-056-FA_and_2018-018-FA_samples_GS-MS.csv); a simplified shapefile of the sediment sample locations and grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction (2017-056-FA_and_2018-018-FA_samples_GS-MS.shp); a browse graphic of sediment sample locations (2017-056-FA_and_2018-018-FA_samples_browse.jpg); and a Federal Geographic Data Committee (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM) metadata file (2017-056-FA_and_2018-018-FA_samples_meta.xml).
  3. What legal disclaimers am I supposed to read?
    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 USGS 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.
  4. How can I download or order the data?
  5. What hardware or software do I need in order to use the data set?
    This dataset contains data available as CSV files and a point shapefile. The CSV files can be read with a text editor. The user must have software capable of reading shapefile format to use the point shapefile.

Who wrote the metadata?

Dates:
Last modified: 23-Nov-2020
Metadata author:
Emily Huntley
U.S. Geological Survey
Geographer/Database Specialist
384 Woods Hole Rd.
Woods Hole, MA
USA

508-548-8700 (voice)
508-457-2310 (FAX)
ehuntley@contractor.usgs.gov
Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/SB_data_release/DR_P9GK29NM/2017-056-FA_and_2018-018-FA_samples_meta.faq.html>
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