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?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
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  5. What is the general form of this data set?
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  7. How does the data set describe geographic features?
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What does this data set describe?

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:

   • https://doi.org/10.5066/P93ATKSC
   • https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/

   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:

   • https://doi.org/10.5066/P93ATKSC
   • https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/

   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)

   Value	Definition
   Mini Seaboss w/ 0.1 sq m Van Veen grab	Sample 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)

   Value	Definition
   GRAVEL	gravel equal to or greater than 50 percent
   GRAVELLY SEDIMENT	gravel equal to or greater than 10 percent, but less than 50 percent
   SAND	sand equal to or greater than 75 percent
   SILTY SAND	sand less than 75 percent and equal to or greater than 50 percent, silt greater than clay, and clay less than 20 percent
   CLAYEY SAND	sand less than 75 percent and equal to or greater than 50 percent, clay greater than silt, and silt less than 20 percent
   SILT	silt equal to or greater than 75 percent
   SANDY SILT	silt less than 75 percent and equal to or greater than 50 percent, sand greater than clay, and clay less than 20 percent
   CLAYEY SILT	silt less than 75 percent and equal to or greater than 50 percent, clay greater than sand, and sand less than 20 percent
   CLAY	clay equal to or greater than 75 percent
   SANDY CLAY	clay less than 75 percent and equal to or greater than 50 percent, sand greater than silt, and silt less than 20 percent
   SILTY CLAY	clay less than 75 percent and equal to or greater than 50 percent, silt greater than sand, and sand less than 20 percent
   SAND SILT CLAY	clay, 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)

   Value	Definition
   Quality grade: A-BJB	A = percent differences between 0% and +- 1.5% assigned by Brian J. Buczkowski.
   Quality grade: B-BJB	B = percent differences between +- 1.5% and +- 3% assigned by Brian J. Buczkowski.
   Quality grade: C-BJB	C = 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?

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:

   • https://doi.org/10.3133/fs14200
   • https://pubs.usgs.gov/fs/fs142-00/

   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:

   • https://doi.org/10.3133/ofr20051001
   • https://pubs.usgs.gov/of/2005/1001/

   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?

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?
   • Availability in digital form:

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV, and shapefile formats, along with the browse graphic and FGDC CSDGM metadata. in format XLSX (version Microsoft Excel O365) Size: 1
     Network links:	https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/data/samples/2019-008-FA_sedsamples.zip https://doi.org/10.5066/P93ATKSC https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV, and shapefile formats, along with the browse graphic and FGDC CSDGM metadata. in format CSV (version exported from Microsoft Excel O365) Size: 1
     Network links:	https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/data/samples/2019-008-FA_sedsamples.zip https://doi.org/10.5066/P93ATKSC https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV, and shapefile formats, along with the browse graphic and FGDC CSDGM metadata. in format Shapefile (version ArcGIS 10.6.1) Size: 1
     Network links:	https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/data/samples/2019-008-FA_sedsamples.zip https://doi.org/10.5066/P93ATKSC https://cmgds.marine.usgs.gov/data/field-activity-data/2019-008-FA/

   • Cost to order the data: none

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)