Location and analyses of sediment samples collected on Stellwagen Bank off Boston, Massachusetts from November 5, 2013 to April 30, 2019 during U.S. Geological Survey field activities

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What does this data set describe?

1. How might this data set be cited?
   Valentine, Page C., 20191226, Location and analyses of sediment samples collected on Stellwagen Bank off Boston, Massachusetts from November 5, 2013 to April 30, 2019 during U.S. Geological Survey field activities: data release DOI:10.5066/P9FWFLPD, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9FWFLPD
   • https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

   Other_Citation_Details:

   Suggested citation: Valentine, P.C., and Cross, V.A., 2019, Location and analyses of sediment samples collected on Stellwagen Bank off Boston, Massachusetts from November 5, 2013 to April 30, 2019 on U.S. Geological Survey field activities: U.S. Geological Survey data release, https://doi.org/10.5066/P9FWFLPD.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -70.457940
   East_Bounding_Coordinate: -70.134620
   North_Bounding_Coordinate: 42.421960
   South_Bounding_Coordinate: 42.084520
   

3. What does it look like?

   https://www.sciencebase.gov/catalog/file/get/5d95153ee4b0c4f70d10a4f7?name=stellwagen_2013_2019_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: 05-Nov-2013

   Ending_Date: 30-Apr-2019

   Currentness_Reference:

   ground condition of when data were collected. Sediment data were collected on 20 cruises from November 5, 2013 to April 30, 2019.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: 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 (679)
   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?

   stellwagen_2013_2019_sedsamps.xlsx

   Sediment sample location and analyses in Excel spreadsheet format. 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, CLASSIFICA instead of CLASSIFICATION, QUALITY_GR instead of QUALITY_GRADE, and QA_QC_COMM instead of QA_QC_COMMENTS), and the software generated FID and shape, defined in the entity and attribute overview section. The last Excel spreadsheet column is omitted from the CSV and shapefile, and is described in the entity and attribute overview section. (Source: U.S. Geological Survey)

   ANALYSIS_ID

   Unique identification number generated in the sediment laboratory of the USGS's Woods Hole Coastal and Marine Science Center. The format of this identifier has changed over time. (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 indicates 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, of sample location. South latitude recorded as negative values. The value is supplied to the lab by the person submitting the sample, so may vary in number of decimal places. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	42.08452
   Maximum:	42.42196
   Units:	Decimal degrees

   LONGITUDE

   Longitude coordinate, in decimal degrees, of sample location. West longitude is recorded as negative values. The value is supplied to the lab by the person submitting the sample, so may vary in number of decimal places. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	-70.45794
   Maximum:	-70.13462
   Units:	Decimal degrees

   DEPTH_M

   Measured depth, in meters, of water overlying sediment sample. The value is supplied to the lab by the person submitting the sample, so may vary in number of decimal places. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	20
   Maximum:	66
   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.
   MINI SEABOSS	sample collected with the SEABOSS system that uses the 0.1 square meter Van Veen grab.
   Van Veen	sample collected with a Van Veen grab.

   MONTH_COLL

   Calendar month sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	1
   Maximum:	12

   DAY_COLL

   Calendar day sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	1
   Maximum:	30

   YEAR_COLL

   Calendar year sample collected. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	2013
   Maximum:	2019

   MONTH_ANAL

   Calendar month sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	1
   Maximum:	12

   DAY_ANAL

   Calendar day sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	1
   Maximum:	31

   YEAR_ANAL

   Calendar year sample completed analysis. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	2013
   Maximum:	2019

   WEIGHT

   Weight of dry sample in grams. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	37.57
   Maximum:	265.71
   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:	70.4
   Units:	weight 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:	18.94
   Maximum:	100.02
   Units:	weight 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:	-0.12
   Maximum:	65.48
   Units:	weight 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:	-0.02
   Maximum:	24.87
   Units:	weight 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:	-2.29
   Maximum:	6.83
   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:	-1.53
   Maximum:	6.08
   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:	0.25
   Maximum:	2.89
   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:	-1.07
   Maximum:	2.96
   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:	-14.2
   Maximum:	104.61
   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:	weight 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:	17.18
   Units:	weight 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:	13.56
   Units:	weight 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:	70.12
   Units:	weight 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:	49.99
   Units:	weight 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:	0.02
   Maximum:	73.06
   Units:	weight 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:	0.05
   Maximum:	75.85
   Units:	weight 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:	0.72
   Maximum:	87.01
   Units:	weight 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:	0.06
   Maximum:	84.54
   Units:	weight 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:	40.64
   Units:	weight 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:	-0.06
   Maximum:	36.45
   Units:	weight 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:	-0.02
   Maximum:	14.99
   Units:	weight percent
   Resolution:	0.01

   PHI_7

   Weight percent of the sample in the 7 phi fraction (nominal diameter of particles greater than or equal to 0.00 8mm, but less than 0.016 mm); fine silt. (Source: USGS East Coast Sediment Texture Database data dictionary)

   Range of values
   Minimum:	-0.03
   Maximum:	21.2
   Units:	weight 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:	-0.1
   Maximum:	23.66
   Units:	weight 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:	-0.01
   Maximum:	17.33
   Units:	weight 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:	-0.01
   Maximum:	7.53
   Units:	weight 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:	-0.01
   Maximum:	1.25
   Units:	weight percent
   Resolution:	0.01

   ANALYST

   Person who performed the grain size or physical properties analysis. Typically represented by the person's initials, or first initial last name. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)

   Value	Definition
   AP	Allison Paquette
   ARP	Allison R. Paquette
   BJB	Brian J. Buczkowski
   KMCMULLEN	Kate McMullen

   ANAL_COMMENTS

   Comments can include information on sample collection, lithology, amount of shell present, and quality grade explanation. This field is not always used, so will have blanks. (Source: U.S. Geological Survey) Character string.

   LITHOLOGY

   General lithologic description of sample. This field is not always filled in, so will have blanks. (Source: modified from USGS East Coast Sediment Texture Database data dictionary) Character string.

   COMMENTS

   Comments can include information on sample collection, lithology, amount of shell present, and quality grade explanation. This field is not always used, so will have blanks. (Source: U.S. Geological Survey) Character string.

   QUALITY_GRADE

   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. Not all samples have a quality grade and are represented by blanks. (Source: modified from USGS East Coast Sediment Texture Database data dictionary)

   Value	Definition
   Quality grade: A	A = percent differences between 0% and +- 1.5%
   Quality grade: B	B = percent differences between ±1.5% and ±3%
   Quality grade: C	C = percent differences between ±3% and ±4.5%
   Quality grade: D	D = percent differences greater than ±4.5%
   Quality grade analyst: BB	Brian Buczkowski
   Quality grade analyst: BJB	Brian J. Buczkowski
   Quality grade analyst: JC	Jason Chaytor

   QA_QC_COMMENTS

   Text field describing the reason a particular quality grade was assigned. Typically for those samples that do not have a quality grade of A. (Source: U.S. Geological Survey) 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. That column contains an explanation of the ANAL_COMM values and how the quality grade is assigned. That column of information is omitted from the CSV and shapefile. The shapefile truncates attribute lablels to 10 characters, so the finall attribute is presented as AQ_QC_COMM in the shapefile. The first row of the spreadsheet is the column heading. The CSV file has the same information and the column definitions are the same - with the last column of the XLSX file omitted (data quality grade explanation). The information in the last column of the XLSX 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%
   Negative weight percents in phi size distributions and gravel-sand-silt percentages may be the result of a lack of fines present in the actual samples. The statistical spreadsheet used to calculate grain size distribution takes measured weights for the coarse fractions (after wet sieving through a 4 phi sieve) and merges it with the cumulative frequency data obtained from the Multisizer for any fine fraction that remains after wet sieving. These equations include determining the percentage of the sample in fine fraction phi weight percents (5 phi to 11 phi). This fine fraction weight is determined by subtracting the wet sieved portion of the sample from the calculated total weight of the sample (determined after calculating and removing the weight of the water in the sample and weight of salt). If there is any excess mass, no matter how small, determined to be in the coarse fraction weights and not in the corrected weight if the entire sample, the calculations subtract this excess weight from the fines phi distribution to make the sum of the weight percents equal 100%.

   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 8)

   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's 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's 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's 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 inspected for biological specimens that were collected for use in studies conducted by scientists at the SBNMS and at collaborating academic institutions. Subsequently the sediment was discarded, after which the sampler was washed in preparation for sampling at the next site. Further information on the SEABOSS can be found in Valentine and others (2000). The samples were collected over a time period from 2013 to 2019 with the process date representing the most recent data collection. 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 8)

   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 diamter) 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. This process was followed for each field activity sample analysis. For these data, those analysis dates ranged from 2013 to 2019.
   A note from the lab was included with one of the returned datasets that has additional information with regards to some of the samples. The ID's are referring to the ANALYSIS_ID.
   The following samples had percent differences in the weight of the coarse fractions that were outside acceptable parameters during original sieving and processing:
   

   GS-000387
   GS-000391
   GS-000402
   GS-000403
   GS-000404
   GS-000405
   GS-000408
   GS-000410
   

   The coarse fractions from original analysis were resieved and reweighed. New weights were within acceptable percent differences of the calculated coarse fraction weight, and these were used to calculate grain size distribution for the above samples.
   The following samples were discarded before being run through the 30 micron aperture tube in the multisizer:
   

   GS-000423
   GS-000424
   GS-000425
   

   For these samples, the fine fraction is reported simply as the weight/percent of total sample below 63 microns.
   The process date refers to the latest processing date. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Brian J. Buczkowski

   Physical Scientist

   384 Woods Hole Rd.

   Woods Hole, MA
   

   USA

   (508) 548-8700 x2361 (voice)

   (508) 457-2310 (FAX)

   bbuczkowski@usgs.gov

   Date: 2019 (process 3 of 8)

   Some of the sample locations (latitude and longitude) were modified to more accurate locations by correcting the values based on the ship navigation file correlated to sample time. Additionally, four station FIELD_NO values were corrected because those station number had already been assigned to stations occupied on cruises prior to this series of cruises aboard the R/V Auk. What follows are the original station numbers and the modified values that occur in this dataset:
   

   4200 to 4415
   4202 to 4417
   4205 to 4419
   4207 to 4420	
   

   The process date refers to the latest processing date. 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 4 of 8)

   The information provided by the sediment laboratory varied slightly during the time period these data represent.
   The first column of information for the older records was DB_ID. That column heading was changed to ANALYSIS_ID, along with the format of the ID value, which starts with GS. For this dataset, that first column is set to ANALYSIS_ID.
   Up until 2016, the last 4 columns of information are ANALYST, ANAL_COMM, LITHOLOGY, and COMMENTS. After that time, the final 4 columns are ANALYST, QUALITY GRADE-ANALYST, LITHOLOGY, COMMENTS. And a new final column is included in the spreadsheets QUALITY GRADING GUIDELINES. This final column is not a per sample piece of information, but rather a column to describe the information in the QUALITY GRADE-ANALYST column. In order to maintain consistency with older datasets, both the ANAL_COMM and QUALITY GRADE-ANALYST fields are included. Sometimes the ANAL_COMM field was used to document the amount (in grams) of shell material removed from the sediment sample.
   In some cases, the ANAL_COMM field contained information pertaining to the quality grade. For consistency, that information was moved to the QUALITY_GRADE column. This edit applied to the following records: ANALYSIS_ID's GS-001059 to GS-001095, GS-001098 to GS-001147, GS-001786 to GS-001827, GS-002287 to GS-002324, GS-002683 to GS-002699, and GS-002738 to GS-002773.
   The records with ANALYSIS_ID's GS-001786 to GS-001827 the information in COMMENTS about the quality grad was moved to AQ_QC_COMMENTS.
   The records with ANALYSIS_ID's GS-002287 to GS-002324 did not have the day of collection in the dataset. This information was added based on the cruise log book.
   Once the individual field activity spreadsheets were modified to all include the same columns of information, the individual spreadsheets were then combined into a single Microsoft Excel spreadsheet in Excel 365. This process step and subsequent process steps were performed by the same person - VeeAnn Cross. 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: 2019 (process 5 of 8)

   Once the individual datasets were combined into a single spreadsheet the following edits were made:
   The format and justification of columns was set to be consistent as well as changing the font to Arial 10.
   The LATITUDE and LONGITUDE values were formatted to have 5 decimal places.
   The following changes were made to provide consistency for query and display:
   Convert all contact values to PVALENTINE (some were already set to that, others were P VALENTINE).
   Change all project values to STELLWAGEN BANK (some were Stellwagen Bank)
   Change all area values to STELLWAGEN BANK (some were Stellwagen Bank).

   Date: 2019 (process 6 of 8)

   The Excel spreadsheet was exported as a CSV UTF-8 file using Excel 365, omitting the last column of information (QUALITY GRADING GUIDELINES) which is not individual station information.

   Date: 2019 (process 7 of 8)

   Using Esri ArcGIS 10.6.1, the CSV file was converted to a shapefile within Esri 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 event theme was added to ArcMap, the data were then converted to a shapefile by right-clicking on the event theme - 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 stellwagen_2013_2019_sedsamps.shp.

   Date: 07-Aug-2020 (process 8 of 8)

   Added keywords section with USGS persistent identifier as theme keyword. 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/

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).
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 20 field activities that occurred from November 2013 to April 2019. However, a sample was not acquired at every station visited during the survey. 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. Additionally, if the station was a plankton tow, sediment samples were not acquired. A total of 679 sediment samples were collected and analyzed for grain size composition from the associated field activities.
5. How consistent are the relationships among the observations, including topology?
   This dataset is based on the original sediment analyses files returned to the scientist after processing at the Woods Hole Coastal and Marine Science Center sediment lab. Over the years, some of the columns of information have varied, but not the sediment analyses columns. All of the field activities used the same research vessel, the R/V Auk. For the most part, the values of the attribute field titled FIELD_NO are in a sequential order (minus stations where samples were not acquired). There are 4 exceptions to this where the original FIELD_NO had to be replaced because the original value had been occupied on a previous cruise. The following FIELD_NO's reflect this: 4200 changed to 4415; 4202 changed to 4417; 4205 changed to 4419; 4207 changed to 4420.
   Negative weight percents in phi size distributions and gravel-sand-silt percentages may be the result of a lack of fines present in the actual samples. The statistical spreadsheet used to calculate grain size distribution takes measured weights for the coarse fractions (after wet sieving through a 4 phi sieve) and merges it with the cumulative frequency data obtained from the Multisizer for any fine fraction that remains after wet sieving. These equations include determining the percentage of the sample in fine fraction phi weight percents (5 phi to 11 phi). This fine fraction weight is determined by subtracting the wet sieved portion of the sample from the calculated total weight of the sample (determined after calculating and removing the weight of the water in the sample and weight of salt). If there is any excess mass, no matter how small, determined to be in the coarse fraction weights and not in the corrected weight if the entire sample, the calculations subtract this excess weight from the fines phi distribution to make the sum of the weight percents equal 100%.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey - ScienceBase

   Denver Federal Center, Building 810, Mail Stop 302

   Denver, CO
   

   USA

   1-888-275-8747 (voice)

   sciencebase@usgs.gov
2. What's the catalog number I need to order this data set? The dataset contains the sediment sample analysis data in three formats - an Excel file (stellwagen_2013_2019_sedsamps.xlsx), a CSV file (stellwagen_2013_2019_sedsamps.csv), and a shapefile (stellwagen_2013_2019_sedsamps.shp and additional files that make up a shapefile). In addition to the sediment analysis files, the dataset contains the browse graphic (stellwagen_2013_2019_sedsamps_browse.jpg) and FGDC CSDGM metadata in XML formats.
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?
   • Availability in digital form:

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV and shapefile formats, along with the FGDC CSDGM metadata. in format XLSX (version Microsoft Excel 365) Size: 1
     Network links:	https://www.sciencebase.gov/catalog/file/get/5d95153ee4b0c4f70d10a4f7 https://doi.org/10.5066/P9FWFLPD https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV and shapefile formats, along with the FGDC CSDGM metadata. in format CSV (version exported from Microsoft Excel 365) Size: 1
     Network links:	https://www.sciencebase.gov/catalog/file/get/5d95153ee4b0c4f70d10a4f7 https://doi.org/10.5066/P9FWFLPD https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

     Data format:	The ZIP file contains the sediment sample analysis in XLSX, CSV and shapefile formats, along with the FGDC CSDGM metadata. in format Shapefile (version Esri ArcGIS 10.6.1) Size: 1
     Network links:	https://www.sciencebase.gov/catalog/file/get/5d95153ee4b0c4f70d10a4f7 https://doi.org/10.5066/P9FWFLPD https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

     Data format:	Web mapping service of the dataset. in format WMS (version 1.3.0) Size: 1
     Network links:	https://www.sciencebase.gov/catalogMaps/mapping/ows/5d95153ee4b0c4f70d10a4f7?service=wms&request=getcapabilities&version=1.3.0 https://doi.org/10.5066/P9FWFLPD https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

     Data format:	Web feature service of the dataset. in format WFS (version 1.0.0) Size: 1
     Network links:	https://www.sciencebase.gov/catalogMaps/mapping/ows/5d95153ee4b0c4f70d10a4f7?service=wfs&request=getcapabilities&version=1.0.0 https://doi.org/10.5066/P9FWFLPD https://www.sciencebase.gov/catalog/item/5d95153ee4b0c4f70d10a4f7

   • 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: 19-Mar-2024

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. (updated on 20240319)

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)