Locations and grain-size analysis results of sediment samples collected in Cape Cod Bay, Massachusetts, in September 2019 by the U.S. Geological Survey during field activity 2019-034-FA (point shapefile and CSV file, GCS WGS 84, MLLW vertical datum)

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Frequently anticipated questions:

What does this data set describe?

Title:
Locations and grain-size analysis results of sediment samples collected in Cape Cod Bay, Massachusetts, in September 2019 by the U.S. Geological Survey during field activity 2019-034-FA (point shapefile and CSV file, GCS WGS 84, MLLW vertical datum)
Abstract:
Accurate data and maps of sea floor geology are important first steps toward protecting fish habitat, delineating marine resources, and assessing environmental changes due to natural or human impacts. To address these concerns the U.S. Geological Survey, in cooperation with the Massachusetts Office of Coastal Zone Management (CZM), comprehensively mapped the Cape Cod Bay sea floor to characterize the surface and shallow subsurface geologic framework. Geophysical data collected include swath bathymetry, backscatter, and seismic reflection profile data. Ground-truth data, including sediment samples, underwater video, and bottom photographs were also collected. This effort is part of a long-term collaboration between the USGS and the Commonwealth of Massachusetts to map the State's waters, support research on the Quaternary evolution of coastal Massachusetts, the influence of sea-level change and sediment supply on coastal evolution, and efforts to understand the type, distribution, and quality of subtidal marine habitats. This collaboration produces high-resolution geologic maps and Geographic Information System (GIS) data that serve the needs of research, management and the public. Data collected as part of this mapping cooperative continue to be released in a series of USGS Open-File Reports and Data Releases (https://www.usgs.gov/centers/whcmsc/science/geologic-mapping-massachusetts-seafloor). This data release provides the geophysical and geologic sampling data collected in Cape Cod Bay during USGS Field Activities 2019-002-FA and 2019-034-FA in 2019.
Supplemental_Information:
See the larger work citation to view the geotagged sea-floor images, locations of bottom images, sea-floor videos, and locations of bottom video tracklines collected during the survey, and to view the affiliated geophysical survey data collected during USGS field activity 2019-002-FA. Support for field activities 2019-002-FA and 2019-034-FA was provided to the USGS by the Massachusetts Office of Coastal Zone Management. For more information about the field activities associated with this project, see https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-002-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-034-FA.
  1. How might this data set be cited?
    Huntley, Emily C., 20220718, Locations and grain-size analysis results of sediment samples collected in Cape Cod Bay, Massachusetts, in September 2019 by the U.S. Geological Survey during field activity 2019-034-FA (point shapefile and CSV file, GCS WGS 84, MLLW vertical datum): data release DOI:10.5066/P99DR4PN, 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., Foster, David S., Andrews, Brian D., Danforth, William W., Baldwin, Wayne E., Huntley, Emily C., Worley, Charles R., and Brothers, Laura L., 2022, High-resolution geophysical and geological data collected in Cape Cod Bay, Massachusetts during USGS Field Activities 2019-002-FA and 2019-034-FA: data release DOI:10.5066/P99DR4PN, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Ackerman, S.D., Foster, D.S., Andrews, B.D., Danforth, W.W., Baldwin, W.E., Huntley, E.C., Worley, C.R., and Brothers, L.L., 2022, High-resolution geophysical and geological data collected in Cape Cod Bay, Massachusetts during USGS Field Activities 2019-002-FA and 2019-034-FA: U.S. Geological Survey data release, https://doi.org/10.5066/P99DR4PN.
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -70.493237
    East_Bounding_Coordinate: -70.135025
    North_Bounding_Coordinate: 42.012512
    South_Bounding_Coordinate: 41.752861
  3. What does it look like?
    https://cmgds.marine.usgs.gov/data-releases/media/2021/10.5066-P99DR4PN/e513edfd10e54f2a94a310592ce1a509/2019-034-FA_samples_browse.jpg (JPEG)
    Map of sediment sample locations in the survey area in Cape Cod Bay, Massachusetts.
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 17-Sep-2019
    Ending_Date: 19-Sep-2019
    Currentness_Reference:
    Data were collected on the following dates: 20190917 and 20190919.
  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):
      • string (49)
    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: Mean Lower Low Water
      Depth_Resolution: 0.1
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
  7. How does the data set describe geographic features?
    2019-034-FA_samples.csv
    CSV file containing grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction for sediment samples collected in Cape Cod Bay, Massachusetts, in September 2019 during USGS field activity 2019-034-FA (49 sample records). A shapefile containing a subset of the attribute fields for all of the sample records is also included in this dataset; 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:41.752861
    Maximum:42.012512
    Units:decimal degrees
    Resolution:0.000001
    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:-70.493237
    Maximum:-70.135025
    Units:decimal degrees
    Resolution:0.000001
    DEPTH_M
    Approximate depth of water in meters (MLLW vertical datum) at the sample location derived using bathymetry data collected during the affiliated geophysical survey (USGS field activity 2019-002-FA). (Source: U.S. Geological Survey)
    Range of values
    Minimum:-37.7
    Maximum:-12.1
    Units:meters
    Resolution:0.1
    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:24.3080
    Maximum:247.5464
    Units:grams
    Resolution:0.0001
    WEIGHT_SHELLS_REMOVED
    Weight in grams of the shells removed from the initial sample. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:1.3650
    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:65.4773
    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:2.5424
    Maximum:99.4846
    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:0.3406
    Maximum:66.3161
    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:0.0027
    Maximum:53.5872
    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 sandSediment whose main phase is sand, but with significant clay.
    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.
    sand silt claySediment with significant (over 20 percent) sand, silt, and clay.
    sandy siltSediment whose main phase is silt, but with significant sand.
    silty claySediment whose main phase is clay, but with significant silt.
    silty sandSediment whose main phase is 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:-3.19
    Maximum:8.15
    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:-1.86
    Maximum:7.56
    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:0.69
    Maximum:3.63
    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:-0.96
    Maximum:4.99
    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:0.75
    Maximum:48.77
    Units:phi
    Resolution:0.01
    PHI_13
    Weight percent of the sample in the 13-phi fraction and smaller (nominal diameter of particles less than 0.00025 mm); fine clay. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    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. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:0
    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. No data value is -9999. (Source: U.S. Geological Survey)
    Range of values
    Minimum:0
    Maximum:8.284
    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:21.929
    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:26.939
    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:0.062
    Maximum:31.069
    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:0.110
    Maximum:21.728
    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:0.093
    Maximum:20.025
    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:0.067
    Maximum:26.248
    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:0.257
    Maximum:68.259
    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:0.222
    Maximum:70.600
    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:0.063
    Maximum:72.611
    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:0.003
    Maximum:80.865
    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
    Maximum:28.455
    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:4.689
    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:6.217
    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:24.644
    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:2.732
    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:27.195
    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.
    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.
    2019-034-FA_samples.shp
    The shapefile, containing 49 point features, has a subset of the fields from the grain-size analysis results CSV file (2019-034-FA_samples.csv). Specifically, STDEV, SKEWNESS, KURTOSIS, and the individual phi measurements (e.g., PHI_13) 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 above for 2019-034-FA_samples.csv 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, WEIGHT_SHE (truncated field name for WEIGHT_SHELLS_REMOVED), GRAVEL_PCT, SAND_PCT, SILT_PCT, CLAY_PCT, CLASSIFICA (truncated field name for CLASSIFICATION), MEDIAN, MEAN, ANALYST, and QA_QC_COMM (truncated field name with the forward slash and space replaced with underscores for QA/QC COMMENTS). (Source: U.S. Geological Survey)
    Entity_and_Attribute_Overview:
    The CSV file contains the sediment analyses as received from the sediment lab. The shapefile is a simplified version of the sediment lab analyses as describted above.
    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)
    • Emily C. Huntley
  2. Who also contributed to the data set?
    The authors acknowledge our fellow participants of the Cape Cod Bay field activities 2019-002-FA (Walter Barnhardt, Luke Bennett, Eric Moore, Alex Nichols, Jake Fredericks, and Dan Kennedy) and 2019-034-FA (Dann Blackwood, Eric Moore, and Alex Nichols); the crew of the M/V Warren Jr and the R/V Tioga; and our sea floor mapping group onshore support team during these surveys (Jane Denny, PJ Bernard, Barry Irwin, and Emile Bergeron).
  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 Mini SEABed Observation and Sampling System (MiniSEABOSS) aboard the Research Vessel (R/V) Tioga during USGS field activity 2019-034-FA (September 17 and 19, 2019). The sediments were analyzed using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction. These data were collected to characterize the sea floor by identifying sediment texture and to ground-truth acoustic data collected during USGS field activity 2019-002-FA.

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: 19-Sep-2019 (process 1 of 8)
    Step 1: Collected data.
    A marine geological survey (field activity 2019-034-FA) was conducted in Cape Cod Bay, Massachusetts, in September 2019. The R/V Tioga occupied one of the target sites, and the MiniSEABOSS was deployed off the vessel's A-frame on the stern of the ship. The MiniSEABOSS was equipped with a modified Van Veen grab sampler, a GoPro HERO4 Black digital camera, an oblique downward-looking SeaViewer 6000 HD Sea-Drop video camera with a topside feed, a Paralenz DiveCamera+ recording backup video, and a dive light to illuminate the sea floor for video and photograph collection. The elements of this particular MiniSEABOSS were held within a stainless-steel frame that measured ~1 x 1 meter. The frame had a stabilizer fin that oriented the system as it drifted over the seabed. Two red lasers were set 20 centimeters apart (both as they were mounted on the MiniSEABOSS frame and as seen in photographs and video on the seabed) for scale measurements. The red laser dots can usually be seen in the sea-floor photos and videos depending on the bottom type and distance to the sea floor. The winch operator lowered the MiniSEABOSS until the sea floor was observed in the topside live video feed. Generally, the vessel and MiniSEABOSS drifted with wind and current for up to a few minutes to ensure a decent photo with a clear view of the sea floor was acquired. The GoPro camera was set to take photos every 2 seconds during a MiniSEABOSS deployment. Bottom video was also recorded during the drift from the oblique downward-looking SeaViewer 6000 HD Sea-Drop video camera directly to a solid-state drive using an Odyssey7 video recorder. Then, 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. At four sites (sites 2019-034-FA-012, 2019-034-FA-016, 2019-034-FA-025, and 2019-034-FA-045), a sample was attempted but was not successfully collected (these areas usually had a cobble, boulder, or rocky seabed). During the survey, DGPS navigation from a Hemisphere R131 DGPS receiver was logged through a DataBridge data logger and QGIS (version 3.0.0) GPS Tools. The DGPS was set to receive fixes at a 1-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 NMEA text format. The GPS data were also overlaid onto the SeaViewer video using a Proteus-V Pro video overlay device. A total of 49 sites were occupied aboard the R/V Tioga with the MiniSEABOSS during field activity 2019-034-FA, and sediment samples were successfully collected at 45 of the 49 sites. Not all of these samples are included in the final dataset due to the presence of cobble (see the Completeness Report above for more information), so this dataset includes the grain-size analysis results for 42 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:
    • Bottom videos
    • Sediment samples
    • Survey log
    • Raw navigation data
    Date: 07-Oct-2019 (process 2 of 8)
    Step 2: Assembled sample information for sediment laboratory.
    The sediment sample times (as recorded in the survey log) were checked by viewing the bottom videos to see when the sampler was lifted off the sea floor at each site and updated with more precise times as appropriate. The latitude and longitude from the video overlay at the time of the sample were also noted for each sediment sample. Approximate depths for each sample were extracted from a composite bathymetry dataset (these depths were later updated in a subsequent process step using bathymetry data collected during the affiliated geophysical survey, USGS field activity 2019-002-FA). 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 the 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 log
    • Bottom videos
    • Composite bathymetry
    Data sources produced in this process:
    • Survey log with updated sample times
    • Sediment sample locations CSV file
    Date: 09-Jan-2020 (process 3 of 8)
    Step 3: Analyzed sediment samples using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction.
    The samples were analyzed in the sediment laboratory at the USGS Woods Hole Coastal and Marine Science Center using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction. A subsample was taken from each sample submitted to the sediment analysis laboratory for the grain-size analysis. The subsamples 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 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. The fine fraction distribution data were added to the data entry spreadsheet. The spreadsheet 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 samples
    • Sediment sample locations CSV file
    Data sources produced in this process:
    • Data entry spreadsheet
    Date: Oct-2020 (process 4 of 8)
    Step 4: 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_xxxx.xlsm, where xxxx is the identifier assigned to the sample submission). Macros in the workbook ("GS_statistics" and "sedimentname") 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-MS_results.xlsx, where xxxx is the batch number assigned to the sample submission). 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:
    • Data entry spreadsheet
    Data sources produced in this process:
    • Final Microsoft Excel spreadsheet (SA13_GS-MS_results.xlsx)
    Date: Dec-2020 (process 5 of 8)
    Step 5: Processed navigation.
    To process the NMEA navigation data, GPSBabel (version 1.7.0) was used to read the GPRMC navigation sentences from the NMEA log files, translate them to waypoints, and write the waypoints to a GPX XML file (nmea_nav_jd260_jd262.gpx). The GPX file was then converted to a shapefile in QGIS (version 3.10.9). New fields for the latitude and longitude were added to the shapefile and calculated to six decimal places. The shapefile was exported as a CSV text file, which was then formatted in Microsoft Excel for Mac (version 16.16), creating a processed NMEA navigation CSV file for the survey (nmea_nav_jd260_jd262.csv).
    Due to an issue with the data logger, the raw navigation data were recorded to NMEA files for only 22 of the 50 sampler deployments. For the remaining 28 deployments, the latitude and longitude recorded on the video overlay were used for the navigation data. To obtain the navigation data from the overlay, first, a command was run to extract a still-image frame grab every 1 second from the videos using FFmpeg (version 4.3.1). Next, a command was run to crop the latitude from each frame grab. The cropped image of the latitude was then converted to text using the optical character recognition engine Tesseract (version 4.1.1) and saved as a text file. These commands were repeated to crop the longitude from each frame grab and convert it to text, and then again to crop and convert the time to text. All the latitude, longitude, and time text files were concatenated and merged into a single text file. This text file was then imported and formatted in Microsoft Excel for Mac, creating a processed video overlay navigation CSV file for the survey (videocrop_coords_and_times.csv). The video overlay navigation data were checked to see if any times were missing. Occasionally, frame grabs were not extracted for the first or last second of the video. These missing frame grabs were identified, and the navigation data from the missing frame grabs were added to the video overlay navigation CSV file.
    Shapefiles of the NMEA and video overlay navigation CSV files were created in ArcGIS (version 10.7.1). The sites with no NMEA navigation were identified, and the video overlay navigation data for those sites were exported as a table. The exported table was added to the NMEA navigation in Microsoft Excel for Mac and saved as a CSV file, creating a final navigation file for the survey (nmea_and_videocrop_nav.csv). This process step and the subsequent process steps 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:
    • Raw navigation data
    • Bottom videos
    Data sources produced in this process:
    • Final navigation file
    Date: Dec-2020 (process 6 of 8)
    Step 6: Updated sediment sample locations and depths.
    The updated sediment sample times (as adjusted by viewing the bottom videos in a previous process step) were matched to the corresponding times in the final navigation file to update the latitude and longitude of each sample in the sediment grain-size analysis results spreadsheet in Microsoft Excel 2016 for Mac. The Microsoft Excel spreadsheet was saved as a CSV file, and a shapefile was created from the CSV file using the XY Table To Point tool in Esri ArcGIS Pro (version 2.4.1). The updated locations were then used to extract approximate depths for the sediment sample locations from the bathymetry data collected during the affiliated geophysical survey (USGS field activity 2019-002-FA; see "2019-002-FA_T20P_Bathymetry_5m_MLLW.tif" in the larger work citation) using the Extract Values to Points tool in Esri ArcGIS Pro. Data sources used in this process:
    • Survey log with updated sample times
    • Final Microsoft Excel spreadsheet (SA13_GS-MS_results.xlsx)
    • Final navigation file
    • Bathymetry (2019-002-FA_T20P_Bathymetry_5m_MLLW.tif)
    Data sources produced in this process:
    • Final Microsoft Excel spreadsheet with updated coordinates and depths
    Date: Nov-2021 (process 7 of 8)
    Step 7: Created final sediment grain-size analysis results CSV file.
    The sediment grain-size analysis results spreadsheet was edited in Microsoft Excel 2016 for Mac 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 log; 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. Finally, the Microsoft Excel spreadsheet was saved as a CSV file (2019-034-FA_samples.csv). Data sources used in this process:
    • Final Microsoft Excel spreadsheet with updated coordinates and depths
    • Survey log
    Data sources produced in this process:
    • Final sediment grain-size analysis results CSV file
    Date: Nov-2021 (process 8 of 8)
    Step 8: Created a shapefile of the sediment sample locations containing a subset of the fields from the grain-size analysis results.
    The CSV file of the sediment grain-size analysis results 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_13] were removed). A shapefile was created from the simplified version of the CSV file using the XY Table To Point tool in Esri ArcGIS Pro (version 2.4.1), and then the field properties (i.e., precision, scale, and length) in the point shapefile were modified as needed. Please note that since the shapefile contains a subset of the grain-size analysis results, 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
    Data sources produced in this process:
    • Final 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:

    Pendleton, E.A., Baldwin, W.E., Barnhardt., W.A., Ackerman, S.D., Foster, D.S., Andrews, B.D., and Schwab, W.C., 2013, Shallow Geology, Sea-floor Texture, and Physiographic Zones of the Inner Continental Shelf from Nahant to Northern Cape Cod Bay, Massachusetts: Open-File Report 2012-1157, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Andrews, B.D., Ackerman, S.D., Baldwin, W.E., and Barnhardt, W.A., 2010, Geophysical and Sampling Data from the Inner Continental Shelf: Northern Cape Cod Bay, Massachusetts: Open-File Report 2010-1006, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Ackerman, Seth D., Foster, David S., Danforth, William W., and Huntley, Emily C., 2019, High-resolution geophysical and sampling data collected off Town Neck Beach in Sandwich, Massachusetts, 2016: data release DOI:10.5066/P9HZHXXV, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Ackerman S.D., Foster D.S., Danforth W.W., and Huntley, E.C., 2019, High-resolution geophysical and sampling data collected off Town Neck Beach in Sandwich, Massachusetts, 2016: U.S. Geological Survey data release, https://doi.org/10.5066/P9HZHXXV.

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_PCT, SAND_PCT, etc.) and the sum of the phi fraction percentages (e.g., PHI_13, PHI_12, etc.) may not always add up to exactly 100.000%.
  2. How accurate are the geographic locations?
    Differential Global Positioning System (DGPS) navigation was used during field activity 2019-034-FA. The DGPS was set to receive fixes at a 1-second interval in geographic coordinates (Geographic Coordinate System [GCS] World Geodetic System of 1984 [WGS 84]). Due to an issue with the data logger, the raw navigation data were recorded to National Marine Electronics Association (NMEA) files for only 22 of the 50 sampler deployments (sites 2019-034-FA-009 through 2019-034-FA-018 and 2019-034-FA-023 through the first deployment at 2019-034-FA-034). For the remaining 28 deployments (sites 2019-034-FA-001 through 2019-034-FA-008, 2019-034-FA-019 through 2019-034-FA-022, and the second deployment at 2019-034-FA-034 through 2019-034-FA-049), the latitude and longitude recorded on the video overlay were used for the navigation data. Due to rounding differences, the navigation recorded to the NMEA files and the video overlay may differ by up to 1 meter. The recorded position of each sediment sample is the position of the DGPS antenna on the survey vessel, located on the aft port side of the R/V Tioga on the rail near the A-frame, not the location of the MiniSEABOSS. The antenna was located approximately 4 meters from the MiniSEABOSS deployment location. No layback or offset was applied to the recorded position. In addition, the MiniSEABOSS 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 5-7 meters. The sites with no successful grab are located along the bottom video trackline at the start of the MiniSEABOSS retrieval.
  3. How accurate are the heights or depths?
    The depths recorded for each sample are referenced to the mean lower low water (MLLW) vertical tidal datum and were derived using bathymetry data collected during the affiliated geophysical survey (USGS field activity 2019-002-FA). Vertical accuracy of the raw data based on system specifications may be approximately 1 percent of water depth (ranging from 0.07 to 0.46 meters based on the water depth range of approximately 7 to 46 meters within the survey area). Additional uncertainty is associated with the correction of the vessel roll, pitch, heave, and yaw (a few millimeters) and the vertical transformation of the bathymetric grid from WGS 84 to MLLW (up to 7.1 centimeters); changes in vessel draft due to water and fuel usage were not considered. See "2019-002-FA_T20P_Bathymetry_5m_MLLW.tif" and the associated metadata in the larger work citation to view the bathymetry data and for more information about the vertical accuracy.
  4. Where are the gaps in the data? What is missing?
    This dataset includes a Comma Separated Values (CSV) file and shapefile of the locations and grain-size analysis results of the sediment samples collected during field activity 2019-034-FA. The shapefile contains a subset of the grain-size analysis results, so users should access the CSV file for the full sediment grain-size analysis results. Physical sediment samples were collected at 45 of the 49 sites occupied during field activity 2019-034-FA. At four sites (sites 2019-034-FA-012, 2019-034-FA-016, 2019-034-FA-025, and 2019-034-FA-045), a sample was attempted but was not successfully collected (these areas usually had a cobble, boulder, or rocky seabed). Locations for all 49 sites are included in this dataset with no data values (i.e., -9999) for those sites with no successful sediment sample. Each deployment of the MiniSEABOSS is generally considered a unique site; however, one site (site 2019-034-FA-034) had two separate deployments because a sediment grab was not successfully collected during the first deployment. The sediment sample location for this site is from the second deployment when a grab sample was successfully collected. Three samples (from sites 2019-034-FA-014, 2019-034-FA-026, and 2019-034-FA-029) contained -6-phi sized clasts that made up between 66.94% and 99.40% of the samples' weights. The presence of these cobbles skewed the resulting statistics for these samples, so the grain-size analysis results for these three sites were left out of the final dataset and have no data values. The samples were analyzed using two methods with separate subsamples: they were first analyzed using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction, and then analyzed using 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. The laser diffraction results and comparison are not included in this data release. Overall, this dataset includes the sediment sample locations for all 49 sites and grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction for 42 of the sites.
  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 MiniSEABOSS. The sediment samples were usually collected at the end of the video trackline (see "2019-034-FA_videos.shp" in the larger work citation), but two samples were collected at the beginning and middle of the transect (sites 2019-034-FA-031 and 2019-034-FA-018, respectively). Three samples (from sites 2019-034-FA-014, 2019-034-FA-026, and 2019-034-FA-029) contained cobbles that skewed the resulting statistics and were left out of the final dataset.

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)
    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
  2. What's the catalog number I need to order this data set? Locations and grain-size analysis results of sediment samples collected in Cape Cod Bay, Massachusetts, in September 2019 by the U.S. Geological Survey during field activity 2019-034-FA. This dataset contains the following files: 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 (2019-034-FA_samples.csv); a shapefile of the sediment sample locations and subset of the grain-size analysis results using the Beckman Coulter Multisizer 3 and sieving of the >= 4-phi fraction (2019-034-FA_samples.shp); a browse graphic of sediment sample locations (2019-034-FA_samples_browse.jpg); and Federal Geographic Data Committee (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM) metadata files in two standard formats (2019-034-FA_samples_meta.txt and 2019-034-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-Apr-2024
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)
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. (updated on 20240423)
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/DRB_data_release/DRB_P99DR4PN/2019-034-FA_samples_meta.faq.html>
Generated by mp version 2.9.51 on Thu Jun 27 10:43:57 2024