Location and analyses of sediment samples collected on Stellwagen Bank during U.S. Geological Survey field activity 2019-008-FA, aboard the R/V Auk, July 30, 31, and August 1, 2019 (ver. 1.1, May 2023)

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What does this data set describe?

Title:
Location and analyses of sediment samples collected on Stellwagen Bank during U.S. Geological Survey field activity 2019-008-FA, aboard the R/V Auk, July 30, 31, and August 1, 2019 (ver. 1.1, May 2023)
Abstract:
This field activity is part of the effort to map geologic substrates of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts. The overall goal is to develop high-resolution (1:25,000) interpretive maps, based on multibeam sonar data and seabed sampling, showing surficial geology and seabed sediment dynamics. This cruise was conducted in collaboration with the Stellwagen Bank National Marine Sanctuary, and the data collected will aid research on the ecology of fish and invertebrate species that inhabit the region. The Sanctuary's research vessel, R/V Auk, visited 53 locations on Stellwagen Bank at which a customized Van Veen grab sampler (SEABOSS) equipped with a video camera and a CTD was deployed in drift mode to collect sediment for grain-size analysis, video imagery of the seabed, and measurements of water column properties.
Supplemental_Information:
Additional information regarding the field activity can be obtained from https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-008-FA.
  1. How might this data set be cited?
    Valentine, Page C., 2020, Location and analyses of sediment samples collected on Stellwagen Bank during U.S. Geological Survey field activity 2019-008-FA, aboard the R/V Auk, July 30, 31, and August 1, 2019 (ver. 1.1, May 2023): data release DOI:10.5066/P93ATKSC, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Valentine, Page C., and Cross, VeeAnn A., 2020, Sea-floor sediment samples, seabed imagery, and CTD instrument data collected on Stellwagen Bank in July and August, 2019, U.S. Geological Survey Field Activity 2019-008-FA (ver. 1.1, May 2023): data release DOI:10.5066/P93ATKSC, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Valentine, P.C., and Cross, V.A., 2020, Sea-floor sediment samples, seabed imagery, and CTD instrument data collected on Stellwagen Bank in July and August, 2019, U.S. Geological Survey Field Activity 2019-008-FA (ver. 1.1, May 2023): U.S. Geological Survey data release, https://doi.org/10.5066/P93ATKSC .
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -70.456940
    East_Bounding_Coordinate: -70.137190
    North_Bounding_Coordinate: 42.421360
    South_Bounding_Coordinate: 42.170197
  3. What does it look like?
    https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/data/samples/2019-008-FA_sedsamps_browse.jpg (JPEG)
    Browse graphic of the sediment sample locations collected on Stellwagen Bank.
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 30-Jul-2019
    Ending_Date: 01-Aug-2019
    Currentness_Reference:
    Ground condition of when data were collected. There were three days of data collection, July 30, 31, and August 1, 2019.
  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 Point data set. It contains the following vector data types (SDTS terminology):
      • Point (44)
    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 0.000001. Longitudes are given to the nearest 0.000001. 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.
      Vertical_Coordinate_System_Definition:
      Depth_System_Definition:
      Depth_Datum_Name: Local surface
      Depth_Resolution: 1
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Attribute values
  7. How does the data set describe geographic features?
    2019-008-FA_sedsamps.xlsx
    The attributes defined refer to the Excel spreadsheet column headings, and are also in the header row of the CSV file. The shapefile has these attributes (except ANALYSIS_I instead of ANALYSIS_ID and CLASSIFICA instead of CLASSIFICATION). Additionally, the shapefile has the software generated FID and shape, which are absent from the Excel spreadsheet and CSV file. (Source: U.S. Geological Survey)
    FID
    Internal feature number. (Source: Esri) Sequential unique whole numbers that are automatically generated.
    Shape
    Feature geometry (Source: Esri) Coordinates defining the features.
    ANALYSIS_ID
    Unique identification number generated in the sediment laboratory of the USGS's Woods Hole Coastal and Marine Science Center. This identifier consists of 2 characters followed by a dash and 6 numerics. (Source: U.S. Geological Survey) Character string.
    FIELD_NO
    Sample name or number as assigned in the field by the Chief Scientist. (Source: USGS East Coast Sediment Texture Database data dictionary) 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: USGS East Coast Sediment Texture Database data dictionary) Character string.
    CRUISE_ID
    Name or number of cruise on which sample collected. The cruise identifier is in the format YYYY-XXX-FA where YYYY is the survey year, XXX is the survey number of that year, and FA is Field Activity. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.
    CONTACT
    Name of Principal Investigator or Chief Scientist responsible for data collection (usually first initial and last name) when available. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.
    AREA
    General geographic area of data collection. Name is general enough to easily locate area on a state map. (Source: USGS East Coast Sediment Texture Database data dictionary) Character string.
    LATITUDE
    Latitude coordinate, in decimal degrees WGS84, of sample location. South latitude recorded as negative values. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:42.170197
    Maximum:42.42136
    Units:Decimal degrees
    LONGITUDE
    Longitude coordinate, in decimal degrees WGS84, of sample location. West longitude is recorded as negative values. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:-70.45694
    Maximum:-70.13719
    Units:Decimal degrees
    DEPTH_M
    Measured depth, in meters, of water overlying sediment at sample time. Depth value is not corrected for tides. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:24
    Maximum:45
    Units:meters
    T_DEPTH
    Top depth of sample, in centimeters, below the sediment-water interface. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0
    Units:centimeters
    B_DEPTH
    Bottom depth of sample, in centimeters, below the sediment-water interface. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:2
    Maximum:2
    Units:centimeters
    DEVICE
    Device used to collect the sample. (Source: USGS East Coast Sediment Texture Database data dictionary)
    ValueDefinition
    Mini Seaboss w/ 0.1 sq m Van Veen grabSample collected with the SEABOSS system that uses the 0.1 square meter Van Veen grab.
    MONTH_COLL
    Calendar month sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:7
    Maximum:8
    DAY_COLL
    Calendar day sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:1
    Maximum:31
    YEAR_COLL
    Calendar year sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:2019
    Maximum:2019
    MONTH_ANAL
    Calendar month sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:10
    Maximum:10
    DAY_ANAL
    Calendar day sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:11
    Maximum:11
    YEAR_ANAL
    Calendar year sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:2019
    Maximum:2019
    WEIGHT
    Weight of dry sample in grams. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:60.23
    Maximum:159.67
    Units:grams
    GRAVEL_PCT
    Gravel content in percent dry weight of the sample (particles with nominal diameters greater than 2 mm; -1 phi and larger). (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:45.65
    Units:percent
    Resolution:0.01
    SAND_PCT
    Sand content in percent dry weight of the sample (particles with nominal diameters less than 2 mm, but greater than or equal to 0.0625 mm; 0 phi through 4 phi). (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:54.28
    Maximum:99.79
    Units:percent
    Resolution:0.01
    SILT_PCT
    Silt content in percent dry weight of the sample (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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0.01
    Maximum:0.66
    Units:percent
    Resolution:0.01
    CLAY_PCT
    Clay content in percent dry weight of the sample (particles with nominal diameters less than 0.004 mm; less than 8 phi). (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.11
    Units:percent
    Resolution:0.01
    CLASSIFICATION
    Sediment description based on rigorous definition usually Shepard (1954) as modified by Schlee and Webster (1967), Schlee (1973), and Poppe and others (2014). These values represent all the possible values as defined in the USGS East Coast Sediment Texture Database data dictionary, and do not necessarily reflect the values present in this dataset. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    ValueDefinition
    GRAVELgravel equal to or greater than 50 percent
    GRAVELLY SEDIMENTgravel equal to or greater than 10 percent, but less than 50 percent
    SANDsand equal to or greater than 75 percent
    SILTY SANDsand less than 75 percent and equal to or greater than 50 percent, silt greater than clay, and clay less than 20 percent
    CLAYEY SANDsand less than 75 percent and equal to or greater than 50 percent, clay greater than silt, and silt less than 20 percent
    SILTsilt equal to or greater than 75 percent
    SANDY SILTsilt less than 75 percent and equal to or greater than 50 percent, sand greater than clay, and clay less than 20 percent
    CLAYEY SILTsilt less than 75 percent and equal to or greater than 50 percent, clay greater than sand, and sand less than 20 percent
    CLAYclay equal to or greater than 75 percent
    SANDY CLAYclay less than 75 percent and equal to or greater than 50 percent, sand greater than silt, and silt less than 20 percent
    SILTY CLAYclay less than 75 percent and equal to or greater than 50 percent, silt greater than sand, and sand less than 20 percent
    SAND SILT CLAYclay, sand, and silt greater than 20 percent each
    MEDIAN
    Middle point in the grain size distribution in phi units. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:-0.67
    Maximum:1.59
    Units:phi
    Resolution:0.01
    MEAN
    Average value in the grain size distribution in phi units. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:-0.81
    Maximum:1.63
    Units:phi
    Resolution:0.01
    STDEV
    Standard deviation (root mean square of the deviations) of the grain size distribution in phi units. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0.52
    Maximum:1.55
    Units:phi
    Resolution:0.01
    SKEWNESS
    Skewness (deviation from symmetrical form) of the grain size distribution. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:-0.63
    Maximum:1.82
    Units:unitless
    Resolution:0.01
    KURTOSIS
    Kurtosis (degree of curvature near the mode) of the grain size distribution. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:-0.88
    Maximum:32.48
    Units:unitless
    Resolution:0.01
    MODE1CLASS
    First mode (particle size that occurs the most number of times) in phi units. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    MODE1FREQ
    Modal strength of the first mode in percent. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    MODE2CLASS
    Second mode in phi units. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    MODE2FREQ
    Modal strength of the second mode in percent. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    MODE3CLASS
    Third mode in phi units. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    MODE3FREQ
    Modal strength of the third mode in percent. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    NMODES
    Number of modes. This calculation is no longer made in the lab, but attribute value is maintained to be consistent with older datasets. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string. Blank
    PHIM5
    Weight percent of the sample in the -5 phi fraction and coarser (nominal diameter of particles greater than or equal to 32 mm); very coarse pebbles to cobbles. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0
    Units:percent
    Resolution:0.01
    PHIM4
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:5.4
    Units:percent
    Resolution:0.01
    PHIM3
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:10.41
    Units:percent
    Resolution:0.01
    PHIM2
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:15.16
    Units:percent
    Resolution:0.01
    PHIM1
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:22.84
    Units:percent
    Resolution:0.01
    PHI_0
    Weight percent of the sample in the 0 phi fraction (nominal diameter of particles greater than or equal to 1 mm, but less than 2 mm); very coarse sand. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0.36
    Maximum:56.75
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:9.41
    Maximum:71.97
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:2.73
    Maximum:71.43
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0.03
    Maximum:21.04
    Units:percent
    Resolution:0.01
    PHI_4
    Weight percent of the sample in the 4 phi fraction (nominal diameter of particles greater than or equal to 0.0625 mm, but less than 0.125 mm); very fine sand. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.07
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.17
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.16
    Units:percent
    Resolution:0.01
    PHI_7
    Weight percent of the sample in the7 phi fraction (nominal diameter of particles greater than or equal to 0.008 mm, but less than 0.016 mm); fine silt. (Source: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0.01
    Maximum:0.21
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.19
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.08
    Units:percent
    Resolution:0.01
    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: USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.03
    Units:percent
    Resolution:0.01
    PHI_11
    Weight percent of the sample in the 11 phi fraction and finer (nominal diameter of particles less than 0.001 mm; fine clay. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    Range of values
    Minimum:0
    Maximum:0.04
    Units:percent
    Resolution:0.01
    ANALYST
    Initials of person who performed the grain size or physical properties analysis. In this case, ARP stands for Allison R. Paquette (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.
    QUALITY_GR
    Quality grades for sample data are assigned based on the calculated percent difference between the weights of the coarse fraction remaining after wet sieving and the sum of all of the weighed fractions after dry sieving the coarse fraction, indicating an estimated differing amount of material which could skew the calculated grain size results. A quality grade is assigned as well as the initials of the person that assigned the grading in the format Q-XX where Q is the quality grade and XX are the initials of the person assigning the grade. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)
    ValueDefinition
    Quality grade: A-BJBA = percent differences between 0% and +- 1.5% assigned by Brian J. Buczkowski.
    Quality grade: B-BJBB = percent differences between +- 1.5% and +- 3% assigned by Brian J. Buczkowski.
    Quality grade: C-BJBC = percent differences between +- 3% and +- 4.5% assigned by Brian J. Buczkowski.
    LITHOLOGY
    General lithologic description of sample. This field is not always filled in, so can have blanks. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.
    COMMENTS
    Comments on sample collection or lithology. This field is not always filled in, so can have blanks. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.
    Entity_and_Attribute_Overview:
    These attribute definitions describe each column of information in the Excel spreadsheet with the exception of additional information in the last column of the Excel spreadsheet which contains an explanation of the QUALITY_GR values and how the quality grade is assigned. That column of information is omitted from the CSV file and shapefile. The first row of the spreadsheet is the column heading. The CSV file has the same information and the same column definitions except the last column of the XLSX file is omitted (data quality grade explanation). The information in the last column of the XLSX file is as follows:
    Data quality grades may be determined by several factors, and any comments or notes that indicate the data for a particular sample may be suspect are included in the results table for that sample under "comments". Quality grades for sample data that do not have any additional comments are assigned based on the calculated percent difference between the weights of the coarse fraction remaining after wet sieving and the sum of all of the weighed fractions after dry sieving the coarse fraction, indicating an estimated differing amount of material which could skew the calculated grain size results.
    A = percent differences between 0% and +-1.5%
    B = percent differences between +-1.5% and +-3%
    C = percent differences between +-3% and +-4.5%
    D = percent differences greater than +-4.5%
    Citations used in attribute definitions:
    Poppe, L.J., McMullen, K.Y., Williams, S.J., and Paskevich, V.F., eds., 2014, USGS east-coast sediment analysis: Procedures, database, and GIS data (ver. 3.0, November 2014): U.S. Geological Survey Open-File Report 2005-1001, http://pubs.usgs.gov/of/2005/1001/.
    Schlee, J., and Webster, J., 1967, A computer program for grain-size data: Sedimentology, v. 8, p. 45-54.
    Schlee, J., 1973, Atlantic continental shelf and slope of the United States -- sediment texture of the northeastern part: U.S. Geological Survey Professional Paper 529-L, 64 p.
    Shepard, F.P., 1954, Nomenclature based on sand-silt-clay ratios: Journal Sedimentary Petrology, v. 24, p. 151-158.
    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)
    • Page C. Valentine
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    U.S. Geological Survey
    Attn: Page C. Valentine
    Research Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    (508) 548-8700 x2239 (voice)
    (508) 457-2310 (FAX)
    pvalentine@usgs.gov

Why was the data set created?

These sediment samples analyzed for grain-size composition, along with seabed imagery, will be used to describe the surficial geological substrates present in the study area.

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: 2019 (process 1 of 5)
    Sediment sampling methods:
    As a part of the process of mapping the sea floor, the USGS developed the SEABed Observation and Sampling System (SEABOSS) to collect samples and video and photographic images of the seabed to aid in the interpretation of seabed sonar imagery. A modified Van Veen sediment grab sampler is mounted in the center of the SEABOSS frame, which ensures the sampler is properly oriented on the seabed when a sample is collected. Before deployment, the sampler bucket jaws are opened by collapsing the extended arms to a near-horizontal position and locking them in place with two catches. The sampler operates passively to sample the seabed; it is not spring loaded.
    To collect a sediment sample, the SEABOSS frame was lowered gently onto the seabed, reducing tension on the cable, which caused the two locking catches to be automatically released by gravity. As the cable was retrieved, the grab sampler arms were pulled upward, closing the bucket around the sediment, and the SEABOSS was lifted off the seabed.
    The SEABOSS was retrieved and set upon a wooden platform that kept the sampler bucket and camera systems above the deck. The sampler arms were held in the upright position manually or by tension on the cable, the two doors on the upper side of the bucket were opened, and the sediment surface was photographed before the sediment was removed. For this project, the upper 2 cm of sediment, representing the surface of the seabed, were removed with a rectangular shovel 2-cm deep and stored in a plastic bag for grain-size analysis. The remaining sediment was dumped into a tray on the deck below the sampler and discarded, after which the sampler was washed in preparation for sampling at the next site. Further information on the SEABOSS can be found in Blackwood and Parolski (2001) and Valentine and others (2000). Person who carried out this activity:
    U.S. Geological Survey
    Attn: Page C. Valentine
    Research Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    (508) 548-8700 x2239 (voice)
    (508) 457-2310 (FAX)
    pvalentine@usgs.gov
    Date: 2019 (process 2 of 5)
    Samples were analyzed in the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center. Coarse fraction (particles greater than 63 microns in diameter) determined by sieve; fine fraction (particles less than 63 microns in diameter) determined by Beckman Coulter Multisizer. See Poppe and others (2014) for analytical specifics for grain size analysis. Sediment statistics were recorded in Microsoft Excel file and returned to the scientist.
    Date: 2020 (process 3 of 5)
    The Excel spreadsheet was exported as an MS-DOS CSV file using Microsoft Excel (O365) omitting the last column of information (QUALITY GRADING GUIDELINES) which is not individual station information. Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
    vatnipp@usgs.gov
    Date: 2020 (process 4 of 5)
    Using ArcGIS 10.6.1, the CSV file was converted to a shapefile within ArcMap using File - Add Data - Add XY data. The CSV file was selected, with the x-coordinate set to LONGITUDE and the y-coordinate set to LATITUDE. The coordinate system of the input coordinates was set to the geographic coordinate system GCS_WGS_1984. Once the XY event layer was added to ArcMap, the data were then converted to a shapefile by right-clicking on the event theme in the contents pane - Data - Export Data. All of the features were exported using the layer's source data for the coordinate system. The output shapefile was set to 2019-008-FA_sedsamps.shp. Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
    vatnipp@usgs.gov
    Date: 11-Apr-2023 (process 5 of 5)
    When the Excel file was converted to a CSV file, the final column of the spreadsheet was not removed. This column contains the explanation of the data quality grades and was intended to be omitted from the CSV. Additionally, when the shapefile was created, this field was carried over and the shapefile was incorrectly named 2019-08-FA_sedsamples.shp. The published Excel file was opened in Excel365. The final column was deleted and the files was saved as an MS-DOS CSV file. The CSV file was converted to a shapefile within ArcMap 10.8.1 using File - Add Data - Add XY data. The CSV file was selected, with the x-coordinate set to LONGITUDE and the y-coordinate set to LATITUDE. The coordinate system of the input coordinates was set to the geographic coordinate system GCS_WGS_1984. Once the XY event layer was added to ArcMap, the data were then converted to a shapefile by right-clicking on the event theme in the contents pane - Data - Export Data. All of the features were exported using the layer's source data for the coordinate system. The output shapefile was set to 2019-008-FA_sedsamps.shp. This work resolved both issues of the extra column and fixing the filename. No other data values were modified. The metadata email was updated to a generic email (20230411). Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
    vatnipp@usgs.gov
  3. What similar or related data should the user be aware of?
    Blackwood, D.S., and Parolski, K.F., 2001, Seabed observation and sampling system: Sea Technology v. 42, no. 2, p.39-43.

    Valentine, P., Blackwood, D., and Parolski, K., 2000, Seabed observation and sampling system: U.S. Geological Survey Fact Sheet FS-142-00, 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:

    Other_Citation_Details:
    This publication has a data dictionary that is used to provide many of the attribute definitions used in this file.

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

  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
    The location information for stations was acquired from a satellite navigation receiver (Furuno satellite compass SC-30 GPS receiver) at two-second intervals with a horizontal accuracy of 10 m. The navigation antenna is located 5.3 m forward of the SEABOSS deployment location. This offset was not accounted for in the navigation acquisition (navigation fixes represent antenna location). The SEABOSS may also drift away from the survey vessel when deployed to the sea floor.
  3. How accurate are the heights or depths?
    Water depth was determined using a Simrad ES60, 120 kHz, single beam echo-sounder using a 120-25 transducer, which detects the seabed to a depth of 800 m. Depth values were rounded to the nearest meter to account for ship motion
  4. Where are the gaps in the data? What is missing?
    These data represent all the sediment samples collected as part of the field activity. However, a sample was not acquired at every station. Samples were discarded at sea if the sediment composition was visibly altered during collection, for example if the sampler did not close properly causing sediment to be lost during recovery of the sample. A total of 44 sediment samples were collected; stations without samples are: 4902, 4905, 4908, 4913, 4926, 4927, 4928, 4930, and 4943.
  5. How consistent are the relationships among the observations, including topology?
    The Excel spreadsheet is the original file returned to the scientist after analysis in sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center. Station 4917 had to have the longitude adjusted to the correct value.

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 Not to be used for navigation.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey
    Attn: Page C. Valentine
    Research Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    (508) 548-8700 x2239 (voice)
    (508) 457-2310 (FAX)
    pvalentine@usgs.gov
  2. What's the catalog number I need to order this data set? 2019-008-FA_sedsamples.zip contains the sediment sample analysis data in three formats - an Excel file (2019-008-FA_sedsamps.xlsx), a CSV file (2019-008-FA_sedsamps.csv), and a shapefile (2019-008-FA_sedsamps.shp and additional files that make up a shapefile). In addition to the sediment analysis files, the ZIP file contains the browse graphic (2019-008-FA_sedsamps_browse.jpg) and FGDC CSDGM metadata in XML format.
  3. What legal disclaimers am I supposed to read?
    Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. 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?
    The ZIP file contains data in XLSX, CSV, and Esri shapefile formats. The user must have software capable of uncompressing the ZIP file and reading the data formats.

Who wrote the metadata?

Dates:
Last modified: 17-May-2023
Metadata author:
U.S. Geological Survey
Attn: VeeAnn A. Cross
Marine Geologist
384 Woods Hole Rd.
Woods Hole, MA

508-548-8700 x2251 (voice)
508-457-2310 (FAX)
whsc_data_contact@usgs.gov
Contact_Instructions:
The metadata contact email address is a generic address in the event the person is no longer with USGS.
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/field_activities/2019_008_fa/2019-008-FA_sedsamps_meta.faq.html>
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