Grain-size analysis data of sediment samples from the beach and nearshore environments at the Pea Island National Wildlife Refuge DUNEX site, North Carolina in 2021

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• What does this data set describe?
  1. How might this data set be cited?
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  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
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  1. How well have the observations been checked?
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What does this data set describe?

1. How might this data set be cited?
   Bales, Robert D., Over, Jin-Si R., Sherwood, Christopher R., Olson, Alexander J., Randall, Noa R., and Suttles, Steven E., 20240122, Grain-size analysis data of sediment samples from the beach and nearshore environments at the Pea Island National Wildlife Refuge DUNEX site, North Carolina in 2021: data release DOI:10.5066/P9O21FQI, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9O21FQI
   • https://www.sciencebase.gov/catalog/item/65777be2d34e952b22746288

   Other_Citation_Details:

   Suggested citation: Bales, R.D., Over, J.R., Sherwood, C.R., Olson, A.J., Randall, N.R., and Suttles, S.E., 2024, Grain-size analysis data of sediment samples from the beach and nearshore environments at the Pea Island National Wildlife Refuge DUNEX site, North Carolina in 2021: U.S. Geological Survey data release, https://doi.org/10.5066/P9O21FQI.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -75.48064
   East_Bounding_Coordinate: -75.46275
   North_Bounding_Coordinate: 35.68073
   South_Bounding_Coordinate: 35.67729
   

3. What does it look like?

   https://www.sciencebase.gov/catalog/file/get/65777be2d34e952b22746288?name=PeaIslandDUNEXsite.JPG (JPEG)

   Image displaying a section of the cross-shore pipe array at the Pea Island National Wildlife Refuge DUNEX site.

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 02-Sep-2021

   Ending_Date: 02-Nov-2021

   Currentness_Reference:

   Ground condition. Sediment samples were collected on the following dates: September 02, 2021, September 14, 2021, September 16, 2021, October 11, 2021, October 21, 2021, October 26, 2021, and November 02, 2021.

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 (95)
   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 0.00001. Longitudes are given to the nearest 0.00001. 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:

      Altitude_System_Definition:

      Altitude_Datum_Name: North American Vertical Datum of 1988
      Altitude_Resolution: 0.001
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method:

      Explicit elevation coordinate included with horizontal coordinates

      Depth_System_Definition:

      Depth_Datum_Name: Local Mean Sea Level
      Depth_Resolution: 0.001
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
      

7. How does the data set describe geographic features?

   DUNEX_GrainSize_Results_v2.csv

   Data spreadsheet containing grain-size analysis results analyzed using the HORIBA laser diffraction unit and sieving of the ≥ -2 phi fraction. These are the attributes for the CSV file. The shapefile has two additional software-generated attributes, FID and Shape, and some modified field names that are truncated and have underscores instead of spaces and hyphens. 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 which is unique to the database. This identifier begins with the assigned multi-letter code GS-, which corresponds to the type of analysis performed on the sample (grain-size analysis), followed by a six-digit number assigned sequentially as samples are registered for analysis. (Source: U.S. Geological Survey) Character string.

   SAMPLE_ID

   The identification value assigned to the sample at the time of collection. This varies from field activity to field activity and the ID can contain any combination of letters and numbers. (Source: U.S. Geological Survey) Character string.

   PROJECT

   Name of project or project number under which samples were taken or data generated; sometimes project name indicates a more specific area. (Source: U.S. Geological Survey) Character string.

   FAN

   The serial number assigned to the dataset field activity during which the sample was collected. This value is in the format YYYY-XXX-FA where YYYY is the year, XXX is the number assigned to the activity within the year, and FA indicates Field Activity. (Source: U.S. Geological Survey) Character string.

   SUBMITTER

   Name of Principal investigator or chief scientist responsible for data collection, or researcher submitting samples for analysis (usually first initial and last name). (Source: U.S. Geological Survey) Character string.

   AREA

   General geographic area of data collection. Name is general enough to easily locate area on a map. (Source: U.S. Geological Survey) Character string.

   LATITUDE

   Latitude coordinate, in decimal-degrees, of sample location. South latitude is recorded as negative values. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	35.67729
   Maximum:	35.68073
   Units:	Decimal degrees
   Resolution:	0.00001

   LONGITUDE

   Longitude coordinate, in decimal degrees, of sample location. West longitude is recorded as negative values. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-75.48064
   Maximum:	-75.46275
   Units:	Decimal degrees
   Resolution:	0.00001

   NAVD88_m

   Height, in meters, of the sediment sample relative to NAVD88 (m). WKID: 5703; using positive up convention. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-13.419
   Maximum:	4.913
   Units:	meters
   Resolution:	0.001

   DEPTH_m

   Measured depth of water overlying sediment at sample time, in meters. Depth value is not corrected for tides. Entries with no depth indicated are left blank. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-5.02
   Maximum:	13.31
   Units:	meters
   Resolution:	0.01

   T_DEPTH

   Top depth of sample below the sediment-water interface, in centimeters. Entries with no depth indicated are left blank. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.0
   Maximum:	0.0
   Units:	centimeters
   Resolution:	0.1

   B_DEPTH

   Bottom depth of sample below the sediment-water interface, in centimeters. Entries with no depth indicated are left blank. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2.0
   Maximum:	4.0
   Units:	centimeters
   Resolution:	0.1

   DEVICE

   Device used to collect the sample. (Source: U.S. Geological Survey)

   Value	Definition
   Shipek Grab	Sampling device consisting of a set of jaws and a deployment mechanism designed to collect sediments or loose substrate from the surface of the sea floor.
   Scoop	Small metal scoop to collect sediments or loose substrate from the surface of the sea floor in shallow water by hand.
   Diver	Hand sample collected by diver hand.

   DATE COLLECTED

   Calendar date indicating when the sample was collected in the format DD-M-YYYY where DD is the day of the month, MMM is the month abbreviation, and YYYY is the year. (Source: U.S. Geological Survey) Character string.

   ANALYSIS COMPLETION DATE

   Calendar date indicating when sample analysis was completed in the format DD-M-YYYY where DD is the day of the month, MMM is the month abbreviation, and YYYY is the year. (Source: U.S. Geological Survey) Character string.

   WEIGHT

   Weight of initial sample in grams. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	8.0488
   Maximum:	10.9904
   Units:	grams
   Resolution:	0.0001

   GRAVEL

   Gravel content in percent dry weight of the sample (particles with nominal diameters greater than 2 mm; -1 phi and larger). (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.0000
   Maximum:	7.4796
   Units:	weight percent
   Resolution:	0.0001

   SAND

   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: U.S. Geological Survey)

   Range of values
   Minimum:	92.4916
   Maximum:	100.0035
   Units:	weight percent
   Resolution:	0.0001

   SILT

   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). (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.0000
   Maximum:	5.2195
   Units:	weight percent
   Resolution:	0.0001

   CLAY

   Clay content in percent dry weight of the sample (particles with nominal diameters less than 0.004 mm; 9 phi and smaller). (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.0000
   Maximum:	0.3420
   Units:	weight percent
   Resolution:	0.0001

   CLASSIFICATION

   Sediment description based on a rigorous definition (Shepard [1954] as modified by Schlee and Webster [1967], Schlee [1973], and Poppe and others [2014]). These values represent the classifications that are present in this dataset, not all possible sediment classifications. (Source: Shepard, F.P., 1954, Nomenclature based on sand-silt-clay ratios: Journal of Sedimentary Petrology, v. 24, p. 151-158. Schlee, J.S., and Webster, Jacqueline, 1967, A computer program for grain-size data: Sedimentology, v. 8, p. 45-54. Schlee, J.S., 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. 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.)

   Value	Definition
   sand	Sediment whose main phase is less than 2 mm, but greater than or equal to 0.062 mm.

   MEAN_PHI

   Mean value of the grain-size distribution in phi units. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.51
   Maximum:	2.80
   Units:	phi
   Resolution:	0.01

   STDEV_PHI

   Standard deviation of the grain-size distribution in phi units. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.58
   Maximum:	1.14
   Units:	phi
   Resolution:	0.01

   SKEWNESS_PHI

   Skewness (unitless deviation from symmetrical form) of the grain-size distribution calculated from phi units. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-2.66
   Maximum:	3.17
   Units:	1
   Resolution:	0.01

   KURTOSIS_PHI

   Kurtosis (unitless degree of curvature near the mode) of the grain-size distribution calculated from phi units. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	1.99
   Maximum:	23.59
   Units:	1
   Resolution:	0.01

   D90_PHI

   Diameter at which 90% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-0.88
   Maximum:	1.86
   Units:	phi
   Resolution:	0.01

   D75_PHI

   Diameter at which 75% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-0.17
   Maximum:	2.21
   Units:	phi
   Resolution:	0.01

   D50_PHI

   Diameter at which 50% of the sample mass is comprised of sediment particles with a diameter less than this value and 50% is larger; middle point in the grain-size distribution in phi units. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.50
   Maximum:	2.59
   Units:	phi
   Resolution:	0.01

   D25_PHI

   Diameter at which 25% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.87
   Maximum:	2.97
   Units:	phi
   Resolution:	0.01

   D10_PHI

   Diameter at which 10% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	1.42
   Maximum:	3.75
   Units:	phi
   Resolution:	0.01

   MEAN_μm

   Mean value of the grain-size distribution in microns. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	180.07
   Maximum:	952.38
   Units:	microns
   Resolution:	0.01

   STDEV_μm

   Standard deviation of the grain-size distribution in microns. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	75.80
   Maximum:	961.49
   Units:	microns
   Resolution:	0.01

   SKEWNESS_μm

   Skewness (unitless deviation from symmetrical form) of the grain-size distribution calculated from microns. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.81
   Maximum:	18.10
   Units:	1
   Resolution:	0.01

   KURTOSIS_μm

   Kurtosis (unitless degree of curvature near the mode) of the grain-size distribution calculated from microns. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	4.37
   Maximum:	364.34
   Units:	1
   Resolution:	0.01

   D10_μm

   Diameter at which 10% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	103.04
   Maximum:	451.08
   Units:	microns
   Resolution:	0.01

   D25_μm

   Diameter at which 25% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	135.84
   Maximum:	583.86
   Units:	microns
   Resolution:	0.01

   D50_μm

   Diameter at which 50% of the sample mass is comprised of sediment particles with a diameter less than this value and 50% is larger; middle point in the grain-size distribution in microns. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	171.29
   Maximum:	744.01
   Units:	microns
   Resolution:	0.01

   D75_μm

   Diameter at which 75% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	216.44
   Maximum:	1112.56
   Units:	microns
   Resolution:	0.01

   D90_μm

   Diameter at which 90% of the sample mass is comprised of sediment particles with a diameter less than this value. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	275.03
   Maximum:	1768.05
   Units:	microns
   Resolution:	0.01

   PHI_16

   16 phi: weight percent of the sample in the 16 phi fraction and smaller (nominal diameter of particles greater than or equal to 0.000015625 mm, less than 0.00003125 mm); colloid. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_15

   15 phi: weight percent of the sample in the 15 phi fraction (nominal diameter of particles greater than or equal to 0.00003125 mm, but less than 0.0000625 mm); colloid. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_14

   14 phi: weight percent of the sample in the 14 phi fraction (nominal diameter of particles greater than or equal to 0.0000625 mm, but less than 0.000125 mm); colloid. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_13

   13 phi: weight percent of the sample in the 13 phi fraction (nominal diameter of particles greater than or equal to 0.000125 mm, but less than 0.00025 mm); fine clay. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_12

   12 phi: weight percent of the sample in the 12 phi fraction (nominal diameter of particles greater than or equal to 0.00025 mm, but less than 0.0005 mm); fine clay. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_11

   11 phi: weight percent of the sample in the 11 phi fraction (nominal diameter of particles greater than or equal to 0.0005 mm, but less than 0.001 mm); fine clay. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_10

   10 phi: weight percent of the sample in the 10 phi fraction (nominal diameter of particles greater than or equal to 0.001 mm, but less than 0.002 mm); medium clay. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_9

   9 phi: weight percent of the sample in the 9 phi fraction (nominal diameter of particles greater than or equal to 0.002 mm, but less than 0.004 mm); coarse clay. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.342
   Units:	weight percent
   Resolution:	0.001

   PHI_8

   8 phi: weight percent of the sample in the 8 phi fraction (nominal diameter of particles greater than or equal to 0.004 mm, but less than 0.008 mm); very fine silt. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	2.380
   Units:	weight percent
   Resolution:	0.001

   PHI_7

   7 phi: weight percent of the sample in the 7 phi fraction (nominal diameter of particles greater than or equal to 0.008 mm, but less than 0.016 mm); fine silt. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	2.155
   Units:	weight percent
   Resolution:	0.001

   PHI_6

   6 phi: weight percent of the sample in the 6 phi fraction (nominal diameter of particles greater than or equal to 0.016 mm, but less than 0.031 mm); medium silt. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.390
   Units:	weight percent
   Resolution:	0.001

   PHI_5

   5 phi: weight percent of the sample in the 5 phi fraction (nominal diameter of particles greater than or equal to 0.031 mm, but less than 0.0625 mm); coarse silt. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.491
   Units:	weight percent
   Resolution:	0.001

   PHI_4

   4 phi: weight percent of the sample in the 4 phi fraction (nominal diameters of particles greater than or equal to 0.0625 mm, but less than 0.125 mm); very fine sand. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	17.608
   Units:	weight percent
   Resolution:	0.001

   PHI_3

   3 phi: weight percent of the sample in the 3 phi fraction (nominal diameter of particles greater than or equal to 0.125 mm, but less than 0.25 mm); fine sand. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.855
   Maximum:	69.820
   Units:	weight percent
   Resolution:	0.001

   PHI_2

   2 phi: weight percent of the sample in the 2 phi fraction (nominal diameter of particles greater than or equal to 0.25 mm, but less than 0.5 mm); medium sand. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	11.393
   Maximum:	68.021
   Units:	weight percent
   Resolution:	0.001

   PHI_1

   1 phi: weight percent of the sample in the 1 phi fraction (nominal diameter of particles greater than or equal to 0.5 mm, but less than 1 mm); coarse sand. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.232
   Maximum:	67.415
   Units:	weight percent
   Resolution:	0.001

   PHI_0

   0 phi: weight percent of the sample in the 0 phi fraction (nominal diameters of particles greater than or equal to 1 mm, but less than 2 mm); very coarse sand. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	21.341
   Units:	weight percent
   Resolution:	0.001

   PHI_-1

   -1 phi: weight percent of the sample in the -1 phi fraction (nominal diameter of particles greater than or equal to 2 mm, but less than 4 mm); very fine pebbles (granules). (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	4.771
   Units:	weight percent
   Resolution:	0.001

   PHI_-2

   -2 phi: weight percent of the sample in the -2 phi fraction (nominal diameter of particles greater than or equal to 4 mm, but less than 8 mm); fine pebbles. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	2.709
   Units:	weight percent
   Resolution:	0.001

   PHI_-3

   -3 phi: weight percent of the sample in the -3 phi fraction (nominal diameter of particles greater than or equal to 8 mm, but less than 16 mm); medium pebbles. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_-4

   -4 phi: weight percent of the sample in the -4 phi fraction (nominal diameter of particles greater than or equal to 16 mm, but less than 32 mm); coarse pebbles. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_-5

   -5 phi: weight percent of the sample in the -5 phi fraction (nominal diameter of particles greater than or equal to 32 mm, but less than 64 mm); very coarse pebbles. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   Units:	weight percent
   Resolution:	0.001

   PHI_-6

   -6 phi: weight percent of the sample in the -6 phi fraction and larger (nominal diameter of particles greater than or equal to 64 mm, but less than 128 mm); cobbles. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.000
   Maximum:	0.000
   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. BJB is Brian J Buczkowski; JDC is Jason D Chaytor; SJW is Sarah J Widlansky; SAG is Simone A Gibson. Multiple sets of initials may be indicated if more than one person worked on the analysis. (Source: U.S. Geological Survey) Character string.

   QUALITY GRADE

   Samples are assigned a quality grade based on the examination of the analytical data. Data quality grades may be determined by several factors, such as consistency with samples collected from a geospatially adjacent location and consistency between replicate runs, 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". When considering replicate run values, if there is over a 10% difference between relative fraction percentages in this sample and the replicate, a quality grade of B will be assigned, over 15% would be assigned a C, and over 20% would be assigned a D. 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%, and D = percent differences greater than ±4.5%. The quality grade is followed by a hyphen and the initials of the person who assigned the grade: BJB is Brian J Buczkowski; JDC is Jason D Chaytor; SJW is Sarah J Widlansky. (Source: U.S. Geological Survey)

   Value	Definition
   A	percent differences between 0% and ±1.5%, there is less than 10% difference in relative fraction percentages between this sample and the replicate, or the results are consistent with expected values.
   B	percent differences between ±1.5% and ±3%, there is greater than 10% and less than 15% difference in relative fraction percentages between this sample and the replicate, or the results are generally consistent with expected values.
   C	percent differences between ±3% and ±4.5%, there is greater than 15% and less than 20% difference in relative fraction percentages between this sample and the replicate, or the results are somewhat consistent with expected values.
   D	percent differences greater than ±4.5%, there is greater than 20% difference in relative fraction percentages between this sample and the replicate, or the results are inconsistent with expected values.

   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.

   Entity_and_Attribute_Overview:

   These data are available in a CSV format and an Esri shapefile. The first line of the CSV file is a header line and those labels are the same as defined in the attribute section. The shapefile has the same fields as the CSV file and two additional attributes, FID (an internal feature number) and Shape (feature geometry). Please note that some of the field names in the shapefile were modified to include underscores instead of spaces and hyphens and truncated to 10 characters since a shapefile has restrictions on field name characters and length (e.g., the "DATE_COLLE" attribute in the shapefile is the same as the "DATE COLLECTED" attribute in the CSV file). Additionally, where negative phi values appear in the field name in the shapefile, they have been replaced with an 'M' for minus, since the shapefile cannot accommodate negative values in the field names (e.g. PHI_-1 is written as PHI_M1).

   Entity_and_Attribute_Detail_Citation: USGS Field Activities 2021-028-FA and 2021-032-FA.
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Robert D. Bales
   • Jin-Si R. Over
   • Christopher R. Sherwood
   • Alexander J. Olson
   • Noa R. Randall
   • Steven E. Suttles
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   Olivia A. De Meo

   U.S. Geological Survey

   Technical Information Specialist

   384 Woods Hole Road

   Woods Hole, MA
   

   US

   508-548-8700 x2356 (voice)

   508-457-2310 (FAX)

   odemeo@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: 02-Sep-2021 (process 1 of 15)

   Nanopod deployment sample collection: Collected 12 sediment samples from the R/V Shearwater using the Shipek surficial grab sampler at nanopod site in the nearshore environment off of Pea Island National Wildlife Refuge, North Carolina, in September 2021.

   Date: 14-Sep-2021 (process 2 of 15)

   Surfzone deployment sample collection: Collected 8 sediment samples via diver at sites of jetted pipes in nearshore environment of Pea Island National Wildlife Refuge, North Carolina, in September 2021.

   Date: 16-Sep-2021 (process 3 of 15)

   Beach sample collection: Collected 20 sediment samples via scoop at jetted pipe sites of Pea Island National Wildlife Refuge, North Carolina, in September 2021.

   Date: 11-Oct-2021 (process 4 of 15)

   Beach sample collection: Collected 4 sediment samples at jetted pipe sites of Pea Island National Wildlife Refuge, North Carolina, in October 2021.

   Date: 21-Oct-2021 (process 5 of 15)

   Surfzone recovery sample collection: Collected 10 sediment samples via diver at sites of jetted pipes in nearshore environment of Pea Island National Wildlife Refuge, North Carolina, in October 2021.

   Date: 26-Oct-2021 (process 6 of 15)

   Beach sample collection: Collected 11 sediment samples via scoop at jetted pipe sites of Pea Island National Wildlife Refuge, North Carolina, in October 2021.

   Date: 02-Nov-2021 (process 7 of 15)

   Nanopod recovery sample collection: Collected 6 sediment samples from the R/V Shearwater using the Shipek surficial grab sampler at nanopod site in the nearshore environment off of Pea Island National Wildlife Refuge, North Carolina, in November 2021.

   Date: 2021 (process 8 of 15)

   The samples were analyzed in the Sediment Laboratory at the USGS Woods Hole Coastal and Marine Science Center using the HORIBA LA-960 laser diffraction unit and sieving of the ≥ -2 phi fraction. Samples submitted to the Sediment Laboratory for grain-size analysis were assigned unique analysis identifiers (ANALYSIS_ID) and divided into batches of no more than 30 samples. There were 4 batches for this sample set: batch_01, batch_02, batch_03, or batch_replicates. The batch named “batch_replicates” refers to samples that were analyzed in the Sediment Laboratory twice to confirm HORIBA LA-960 accuracy. Each batch is entered into a Microsoft Excel data entry spreadsheet (LD Worksheet Template_SS05.xlsx, where SS05 is the identifier assigned to the sample submission) to record the initial and dried sample weights, as well as the sieved coarse fraction weights. Each batch was also entered into macro-enabled Microsoft Excel data entry spreadsheets (GrainSizeWorksheet_LD1-30_SS05(batch_nn).xlsm or GrainSizeWorksheet_LD31-60_SS05(batch_nn).xlsm), where "LD1-30” and “LD31-60” refer to the pre-labeled and weighed glass laser diffraction vials in which the samples will be run, and “batch_nn” refers to the sample batch) to record the measurement data coming from the laser diffraction unit and incorporate the initial, dried, and sieved weights. The sample submission identifier for these samples is "SS05".
   About 10 to15 grams of wet sediment were placed in a pre-weighed beaker and the gross weight was recorded. The sample was wet sieved through a 4 mm (No. 5) sieve. Any remaining coarse material was oven dried at 100°C in a pre-weighed beaker and weighed again when dry. This coarse fraction was dry sieved to determine the individual weights of the -2 to -5 phi fractions, and the weights were recorded in the data entry spreadsheet LD Worksheet Template_SS05.xlsx. The fine fraction in water was collected in a pre-labeled and weighed glass laser diffraction vial. If there was any coarse fraction remaining in the sieve from wet sieving, this vial was also oven dried at 100°C and weighed when dry. If there was no coarse fraction remaining from wet sieving, the sample proceeded directly to processing for analyses by the HORIBA LA-960 laser diffraction unit.
   Dry, fine fractions ready for analysis by the HORIBA laser diffraction unit were rehydrated with distilled water. Fifteen (15) ml of pre-mixed 40 g/l sodium hexametaphosphate [(NaPO3)6] was added to each sample. If the height of the fluid in the laser diffraction vial was less than 5 cm, more distilled water was added to raise the level to no more than 8 cm in the vial. The samples were gently stirred, covered, and allowed to soak for at least 1 hour (for samples that were not dried) or up to 24 hours (for samples that were dried). Soaked vials were placed into an ultrasonic bath and run for 10 minutes at a frequency of 37 Hz with a power level of 100. If the samples appeared to be fully disaggregated, they were placed into pre-determined autosampler locations and fine fraction grain-size distributions were determined using the HORIBA LA-960 for Windows software. The fine fraction distribution data was added to the appropriate data entry spreadsheets (GrainSizeWorksheet_LD1-30_SS05(batch_nn).xlsm or GrainSizeWorksheet_LD31-60_SS05(batch_nn).xlsm). The spreadsheet was used to calculate a continuous phi class distribution from the original fractions. Person who carried out this activity:
   

   Brian Buczkowski

   U.S. Geological Survey

   Physical Scientist, Sediment Laboratory Manager

   384 Woods Hole Road

   Woods Hole, MA
   

   508-548-8700 x2310 (voice)

   bbuczkowski@usgs.gov

   Date: 2021 (process 9 of 15)

   A continuous phi class distribution from the original fractions was transposed to the "results" tab in the macro-enabled Microsoft Excel data entry workbook (GrainSizeWorksheet_LD1-30_SS05(batch_nn).xlsm or GrainSizeWorksheet_LD31-60_SS05(batch_nn).xlsm, where SS05 is the identifier assigned to the sample submission, “LD1-30” and “LD31-60” refer to the pre-labeled and weighed glass laser diffraction vials in which the samples were run, and “batch_nn” refers to the sample batch). Macros in the workbook (“GS_MoM_Arithmatic,” "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 the final Microsoft Excel spreadsheet (SS05_GS-LD_results.xlsx). 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.

   Date: 01-Jul-2022 (process 10 of 15)

   The results from the final Microsoft Excel spreadsheet (SS05_GS-LD_results.xlsx) were imported into Microsoft Excel for Microsoft 365 MSO 32-bit and the significant figures were adjusted appropriately. The final data was then saved as a .csv file and header names were changed in Notepad++ v8.4.1. Person who carried out this activity:
   

   Robert D. Bales

   U.S. Geological Survey

   Oceanographer

   11 Woods Hole Road

   Woods Hole, MA
   

   508-457-8700 x2257 (voice)

   rbales@usgs.gov

   Date: 31-Aug-2022 (process 11 of 15)

   Elevations of the sediment samples were extracted from topographic and bathymetric maps of the study site provided in Over and others (2022) using the maps created with data collected closest to the sample collection date. This may be up to twelve days apart, but it is not expected that the elevation values would differ by more than half a meter. Person who carried out this activity:
   

   Jin-Si R. Over

   U.S Geological Survey, Woods Hole Coastal and Marine Science Center

   Geographer

   384 Woods Hole Rd

   Woods Hole, MA
   

   508-548-8700 x2297 (voice)

   jover@usgs.gov

   Date: 02-Sep-2022 (process 12 of 15)

   Elevations (NAVD88_M) were transformed to height referenced to local mean sea level (LMSL) using VDatum Online v. 4.4.2, developed by NOAA's National Geodetic Survey (NGS). These values were calculated for DEPTH_M. Visit https://vdatum.noaa.gov/welcome.html for more information about VDatum. This process step and the following process step were performed by the same person, Robert Bales. Person who carried out this activity:
   

   Robert D. Bales

   U.S. Geological Survey

   Oceanographer

   11 Woods Hole Rd

   Woods Hole, MA
   

   508-457-8700 x2257 (voice)

   rbales@usgs.gov

   Date: 02-Sep-2022 (process 13 of 15)

   The CSV file was imported into ArcMAP 10.8.1 and a shapefile (.shp) and associated files were saved using the XY to Table function.

   Date: 2023 (process 14 of 15)

   Version 2.0: Grain size data were reprocessed in September 2023 as part of a corrective action taken after an issue was identified in the Microsoft Excel data processing workbook (version 1.0) used to calculate grain size statistics and phi class distributions from raw data obtained from the Sediment Laboratory's Horiba LA-960 laser diffraction unit. Data coming from the instrument and weights recorded from sieving were not faulty. An error was found in a formula embedded in the workbook that translates data originally formatted in columns into rows. There are 96 bins of particle size distribution information recorded for each sample run on the instrument. The error resulted in a shifting of data by one bin (the values in bin number one in the column of data coming from the machine were translated into the position for bin number 2 in the corresponding row, and so on). Overall, the resulting data coming from version 1.0 of the processing workbook are affected by a slight shift in grainsize distribution. This error in the formula was corrected in September 2023 and a new version of the workbook (version 2.1) was generated and approved for use in the Sediment Laboratory. In addition, labeling for the logarithmic d10, d25, d75 and d90 headings was updated. Note the differing order of these values between Logarithmic and Arithmetic Method of Moments statistics. All affected grain size datasets using data from the laser diffraction unit have been reprocessed, reviewed, and prepared for release. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Brian Buczkowski

   Physical Scientist, Sediment Laboratory Manager

   Woods Hole Coastal and Marine Science Center

   Woods Hole, MA
   

   508-548-8700 x2361 (voice)

   508-457-2310 (FAX)

   gs-wh_sedlab@usgs.gov

   Date: 06-Dec-2023 (process 15 of 15)

   The results from the final Microsoft Excel spreadsheet (SS05_GS-LD_results_v2.xlsx) were imported into MATLAB R2023a, the column headings were given unique names, and the significant figures were adjusted appropriately. The final data were then exported to a CSV file. A second CSV file was made to create a shapefile where negative phi values appearing in the field names were replaced with an 'M' for minus, since the shapefile cannot accommodate negative values in the field names (e.g. PHI_-1 is written as PHI_M1). This CSV file was imported into ArcGIS Pro 3.1.0 and a shapefile (.shp) and associated files were saved. Person who carried out this activity:
   

   Olivia De Meo

   U.S. Geological Survey

   Technical Information Specialist

   384 Woods Hole Road

   Woods Hole, MA
   

   (508) 548-8700 x2356 (voice)

   odemeo@usgs.gov

3. What similar or related data should the user be aware of?
   Over, Jin-Si R., Sherwood, Christopher R., Traykovski, Peter A., Olson, Alex J., Randall, Noa R., Marsjanik, Eric, and Brosnahan, Sandra M., 2022, DUNEX topographic, bathymetric, and supporting GPS data collected in Pea Island National Wildlife Refuge, North Carolina 2020-2021: data release DOI:10.5066/P9DPZZG2, U.S. Geological Survey, Sciencebase, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

   Online Links:

   • https://doi.org/10.5066/P9DPZZG2

   Other_Citation_Details:

   The topobathy products in this publication are used to extract sediment sample elevations and provide additional context for the Pea Island field site.

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

1. How well have the observations been checked?
   Laboratory analyses were conducted at USGS Woods Hole Coastal and Marine Science Center Sediment Laboratory using a HORIBA LA-960 laser diffraction size analyzer with manufacturer guaranteed accuracy of +/- 0.6 percent. The performance of every HORIBA LA-960 laser diffraction unit is verified with National Institute of Standards and Technology (NIST) traceable mono- and polydisperse size standards. Due to rounding, the sum of the aggregate class percentages (e.g., GRAVEL, SAND, etc.) and the sum of the phi fraction percentages (e.g., PHI_16, PHI_15, etc.) may not always add up to exactly 100.000 percent.
2. How accurate are the geographic locations?
   Horizontal position was determined using a Garmin GPSMAP 78sc handheld GPS. The expected absolute, horizontal accuracy is stated to be 3 to 5 m at the 95 percent confidence level using the WAAS setting. Additional sources of error in the position for the water sample locations are caused by the offset from the GPS and the exact location of the Shipek grab sampler at the time the sample was taken, which could be as large as 2 m; therefore, overall expected accuracy of the reported horizontal position for these water sample locations is on the order of 7 m or better. Horizontal position for hand samples DX_20 through DX_32dup were determined with SP80 RTK systems. The SP80 RTK systems used to collect location data have a theoretical horizontal accuracy of 5 to10 cm; however, horizontal accuracy for samples DX_23 to DX_30 may be up to 0.5m because horizontal position was determined at a jetted beach pipe and hand sample was collected beside the jetted pipe.
3. How accurate are the heights or depths?
   Elevations of the sediment samples are provided in reference to NAVD88 (m). These values were extracted from topobathy grids either from 2022-09-11 or 2022-10-20 that have vertical accuracies of 0.1 m or better. DEPTH_M values were transformed from NAVD88 elevations using VDatum, decreasing the accuracy to about .12 m or better. Grids were not necessarily created from data the same day as sediment samples were collected, rather the closest grid was chosen to extract values from and some geomorphological change is to be expected, but on scales less than 1 meter.
4. Where are the gaps in the data? What is missing?
   This dataset represents all the samples that were collected. Some sample IDs are followed by “dup” meaning “duplicate”, for an additional sample collected at the same location. Samples ending with “(replicate)” are samples that were analyzed in the Sediment Laboratory twice to confirm HORIBA LA-960 accuracy.
5. How consistent are the relationships among the observations, including topology?
   Sediment samples were collected using a Shipek grab sampler (Shipek Grab), small metal scoop (Scoop) or by diver’s hand (Diver). Samples were shipped from the field site in a dark cooler with ice to the USGS Woods Hole Coastal and Marine Science Center. They were then stored in a refrigerated and dark location until analyzed in the laboratory on the HORIBA LA-960 laser diffraction size analyzer as described in the process steps below.

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
   

   United States

   1-888-275-8747 (voice)

   sciencebase@usgs.gov
2. What's the catalog number I need to order this data set? This dataset contains grain-size analysis of sediment samples collected from Pea Island National Wildlife Refuge, North Carolina in 2021 (DUNEX_GrainSize_Results_v2.csv and DUNEX_GrainSize_Results_v2.shp).
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by 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. 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.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	Comma Separated Values (CSV) file saved from Microsoft Excel for Microsoft 365 MSO 32-bit. in format CSV Size: 0.049
     Network links:	https://www.sciencebase.gov/catalog/file/get/65777be2d34e952b22746288 https://www.sciencebase.gov/catalog/item/65777be2d34e952b22746288 https://doi.org/10.5066/P9O21FQI

     Data format:	Esri shapefile (.shp) and associated files created by importing the grain-size data into ArcGIS. The attribute headers include up to the first 10 characters from the csv file header labels. in format SHP Size: 0.407
     Network links:	https://www.sciencebase.gov/catalog/file/get/65777be2d34e952b22746288 https://www.sciencebase.gov/catalog/item/65777be2d34e952b22746288 https://doi.org/10.5066/P9O21FQI

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 22-Jan-2024

Metadata author:

Olivia A. De Meo

U.S. Geological Survey

Technical Information Specialist

384 Woods Hole Road

Woods Hole, MA

US

508-548-8700 x2356 (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:

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