Sedimentary Data Collected in April 2016 From Old Tampa Bay, Florida (U.S. Geological Survey Field Activity Number 2016–327–FA)

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What does this data set describe?

1. How might this data set be cited?
   Marot, Marci E., and Wheaton, Cathryn J., 20170628, Sedimentary Data Collected in April 2016 From Old Tampa Bay, Florida (U.S. Geological Survey Field Activity Number 2016–327–FA):.

   This is part of the following larger work.
   Marot, Marci E., Wheaton, Cathryn J., and Smith, Christopher G., 20170628, Seasonal Sedimentary Data Collected From Old Tampa Bay, Florida, 2015-2016: U.S. Geological Survey Data Release doi:10.5066/F7K64G99, U.S. Geological Survey, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/F7K64G99

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -82.67505
   East_Bounding_Coordinate: -82.67290
   North_Bounding_Coordinate: 28.02010
   South_Bounding_Coordinate: 27.94195
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 04-Apr-2016

   Ending_Date: 04-Apr-2016

   Currentness_Reference:

   Ground condition

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

   Geospatial_Data_Presentation_Form: Multimedia presentation
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      
   2. What coordinate system is used to represent geographic features?
      
7. How does the data set describe geographic features?

   16FWR05_SiteLocations.xlsx

   Microsoft Excel workbook defining the station locations and water depth of sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). (Source: USGS)

   16FWR05_SiteLocations.csv

   Comma-separated values text file defining the station locations and water depth of sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). (Source: USGS)

   16FWR05_CTDProfiles.xlsx

   Microsoft Excel workbook listing conductivity, temperature, depth, and associated water parameter profiles for the water column at the site locations of sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA) recorded by a SonTek Castaway CTD. The results for each station location are provided on its own tab. (Source: SonTek)

   16FWR05_CTDProfiles.csv

   Comma-separated values text file listing conductivity, temperature, depth, and associated water parameter profiles for the water column at the site locations of sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA) recorded by a SonTek Castaway CTD. (Source: SonTek)

   16FWR05_SedimentPhysicalProperties.xlsx

   Microsoft Excel workbook listing water content, porosity, bulk density and loss-on-ignition data for sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). The results for each core are provided on its own tab. (Source: USGS)

   16FWR05_SedimentPhysicalProperties.csv

   Comma-separated values text file listing water content, porosity, bulk density and loss-on-ignition data for sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). (Source: USGS)

   16FWR05_GrainSize.xlsx

   Microsoft Excel workbook summarizing grain-size parameters for the uppermost ten 1-cm depth intervals from sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). The averaged results for each sample, including the number of runs used, the standard deviation of the averaged results, and graphical class-size distributions, are provided for each core on its own tab. (Source: USGS)

   16FWR05_GrainSize.csv

   Comma-separated values text file summarizing grain-size parameters for the uppermost ten 1-cm depth intervals from sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). The averaged results for each sample, including the number of runs used, the standard deviation of the averaged results, and graphical class-size distributions, are provided. (Source: USGS)

   16FWR05_GammaSpectroscopy.xlsx

   Microsoft Excel workbook listing gamma spectroscopy radiochemistry results for the uppermost five 1-cm depth intervals from sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). The results for each core are provided on its own tab. (Source: USGS)

   16FWR05_GammaSpectroscopy.csv

   Comma-separated values text file listing gamma spectroscopy radiochemistry results for the uppermost five 1-cm depth intervals from sediment cores collected in Old Tampa Bay, Florida (USGS FAN 2016-327-FA). (Source: USGS)

   Site ID

   Site identifier assigned by USGS scientist (Source: USGS) Character string

   Sampling Date

   Date identifier (Source: USGS)

   Range of values
   Minimum:	04/04/2016
   Maximum:	04/04/2016
   Units:	mm/dd/yyyy
   Resolution:	1

   Latitude

   Latitude of station location, in decimal degrees recorded by a Garmin GSPMAP 1040xs GPS receiver (Source: USGS)

   Range of values
   Minimum:	27.94199
   Maximum:	28.01996
   Units:	Decimal degrees
   Resolution:	0.00001

   Longitude

   Longitude of site location, in decimal degrees recorded by a Garmin GSPMAP 1040xs GPS receiver (Source: USGS)

   Range of values
   Minimum:	-82.67503
   Maximum:	-82.67302
   Units:	Decimal degrees
   Resolution:	0.00001

   Water Depth (m)

   Water depth at station location, in meters (Source: USGS)

   Range of values
   Minimum:	2.3
   Maximum:	3.8
   Units:	Meters
   Resolution:	0.1

   Cast Date and Time (Local)

   Date and time of SonTek Castaway CTD cast in Eastern Daylight Time (Source: SonTek)

   Range of values
   Minimum:	04/04/2016 10:30
   Maximum:	04/04/2016 13:47
   Units:	mm/dd/yyyy hh:mm
   Resolution:	1

   Latitude (WGS 84)

   Latitude of cast location, in decimal degrees recorded by the SonTek Castaway CTD (Source: SonTek)

   Range of values
   Minimum:	27.94198
   Maximum:	28.01996
   Units:	Decimal degrees
   Resolution:	0.00001

   Longitude (WGS 84)

   Longitude of cast location, in decimal degrees recorded by the SonTek Castaway CTD (Source: SonTek)

   Range of values
   Minimum:	-82.67507
   Maximum:	-82.67301
   Units:	Decimal degrees
   Resolution:	0.00001

   Pressure (dbar)

   Water pressure profile in decibars recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	0.15
   Maximum:	3.99
   Units:	Decibars
   Resolution:	0.01

   Depth (m)

   Water column depth profile in meters recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	0.15
   Maximum:	4.02
   Units:	Meters
   Resolution:	0.01

   Temperature (°C)

   Water column temperature in degrees Celsius recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	22.8
   Maximum:	24.5
   Units:	Degrees Celsius
   Resolution:	0.1

   Conductivity (uS/cm)

   Water column conductivity profile in microsiemens per centimeter recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	31270.9
   Maximum:	35609.8
   Units:	Microsiemens per centimeter
   Resolution:	0.1

   Specific Conductance (uS/cm)

   Water column specific conductance profile in microsiemens per centimeter recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	32296.8
   Maximum:	36011.2
   Units:	Microsiemens per centimeter
   Resolution:	0.1

   Salinity (PSS)

   Water column salinity profile measured on the practical salinity scale recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	20.1
   Maximum:	22.7
   Units:	Practical salinity scale
   Resolution:	0.1

   Sound Velocity (m/s)

   Speed of sound in water profile in meters per second recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	1514.4
   Maximum:	1519.9
   Units:	Meters per second
   Resolution:	0.1

   Density (kg/m^3)

   Water column density profile in kilograms per cubic meter recorded by a SonTek Castaway CTD at each core location (Source: SonTek)

   Range of values
   Minimum:	1012.6
   Maximum:	1014.6
   Units:	Kilograms per cubic meter
   Resolution:	0.1

   Core ID

   Core identifier assigned by USGS scientist (Source: USGS) Character string

   Depth (cm)

   Depth interval in centimeters measured below the core surface (Source: USGS)

   Range of values
   Minimum:	0-1
   Maximum:	21-22
   Units:	Centimeters
   Resolution:	0.5

   Water Content (g-water/g-wet)

   The ratio of the mass of water to the mass of wet sediment (Source: USGS)

   Range of values
   Minimum:	0.31
   Maximum:	0.78
   Units:	Grams of water per grams of wet sediment
   Resolution:	0.01

   Porosity (cm^3-voids/cm^3-wet)

   Porosity of the sediment interval (Source: USGS)

   Range of values
   Minimum:	0.53
   Maximum:	0.90
   Units:	Cubic centimeter of void space per cubic centimeter of wet sediment
   Resolution:	0.01

   Dry Bulk Density (g/cm^3)

   Dry bulk desnsity of the sediment interval (Source: USGS)

   Range of values
   Minimum:	0.23
   Maximum:	1.17
   Units:	Grams per cubic centimeter
   Resolution:	0.01

   Loss On Ignition (g-OM/g-dry)

   The ratio of the mass of organic matter combusted at 550 Celsius to the pre-combusted mass of dry sediment (Source: USGS)

   Range of values
   Minimum:	0.017
   Maximum:	0.132
   Units:	Grams of organic matter per grams of dry sediment
   Resolution:	0.001

   Be-7 (dpm/g)

   Beryllium-7 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	Not Detected
   Maximum:	3.42
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Be-7 Error (+/- dpm/g)

   Beryllium-7 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	Null
   Maximum:	0.66
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Be-7 Inventory (dpm/cm^2)

   Beryllium-7 activity inventory measured in disintegrations per minute per square centimeter decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	Not Detected
   Maximum:	0.78
   Units:	Disintegrations per minute per square centimeter
   Resolution:	0.01

   Be-7 Inventory Error (+/- dpm/cm^2)

   Beryllium-7 inventory error measured in disintegrations per minute per square centimeter (Source: USGS)

   Range of values
   Minimum:	Null
   Maximum:	0.20
   Units:	Disintegrations per minute per square centimeter
   Resolution:	0.01

   Cs-137 (dpm/g)

   Cesium-137 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	Not Detected
   Maximum:	0.32
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Cs-137 Error (+/- dpm/g)

   Cesium-137 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	Null
   Maximum:	0.11
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Pb-210 (dpm/g)

   Lead-210 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	2.61
   Maximum:	12.92
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Pb-210 Error (+/- dpm/g)

   Lead-210 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	0.18
   Maximum:	0.64
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Ra-226 (dpm/g)

   Radium-226 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	1.34
   Maximum:	3.47
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Ra-226 Error (+/- dpm/g)

   Radium-226 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	0.06
   Maximum:	0.21
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Th-234 (dpm/g)

   Thorium-234 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	1.42
   Maximum:	6.56
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Th-234 Error (+/- dpm/g)

   Thorium-234 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	0.18
   Maximum:	0.59
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   K-40 (dpm/g)

   Potassium-40 specific activity measured in disintegrations per minute per gram of dry sediment decay-corrected to the date of field collection (Source: USGS)

   Range of values
   Minimum:	3.49
   Maximum:	19.40
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   K-40 Error (+/- dpm/g)

   Potassium-40 specific activity counting error measured in disintegrations per minute per gram of dry sediment (Source: USGS)

   Range of values
   Minimum:	0.50
   Maximum:	2.25
   Units:	Disintegrations per minute per gram
   Resolution:	0.01

   Entity_and_Attribute_Overview:

   The detailed attribute descriptions for the grain size workbooks are provided in the included data dictionary (Grain_Size_Data_Dictionary.pdf). These metadata are not complete without this file.

   Entity_and_Attribute_Detail_Citation:

   Data dictionary for grain-size data tables, in: Marot, M.E., Wheaton, C.J., Smith, C.G., 2017, Seasonal sedimentary data collected from Old Tampa Bay, Florida, 2015-2016: U.S. Geological Survey data release, https://doi.org/10.5066/F7K64G99.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Marci E. Marot
   • Cathryn J. Wheaton
2. Who also contributed to the data set?

   U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center

3. To whom should users address questions about the data?
   U.S. Geological Survey

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   mmarot@usgs.gov

Why was the data set created?

Dissemination of processed sediment data from sediment core intervals collected from three sites in Old Tampa Bay, Florida, in April 2016 (USGS FAN 2016-327-FA).

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 2016 (process 1 of 8)

   At three stations in Old Tampa Bay, diver-assisted push cores were collected with 10.2-cm diameter polycarbonate barrels. Upon retrieval, the cores were visually inspected for an undisturbed sediment-water interface, cores with disturbed sediment surfaces were discarded and resampled. If multiple coring attempts were necessary, the boat was moved several feet to avoid resampling where the sediment had been disturbed by previous attempts, the new location was recorded on the GPS. Replicate cores were collected at sites TB01 and TB02. Core lengths ranged between 13 and 25 cm. Cores accepted for analysis were wrapped in opaque plastic to prevent light penetration. The cores were transported upright to the SPCMSC laboratory for sectioning. Water column profiles of temperature, conductivity, and pressure were recorded with a SonTek Castaway-CTD sensor at each site. Site coordinates were recorded on a vessel-mounted Garmin GPSMAP 1040xs Global Positioning (GPS) receiver. Site locations and CTD measurements are reported in Excel spreadsheets. Comma-separated values data files containing the tabular data in plain text are included in the download files. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Data sources produced in this process:

   • 16FWR05_FieldLogs.pdf
   • 16FWR05_SiteLocations.zip
   • 16FWR05_CTDProfiles.zip

   Date: 2016 (process 2 of 8)

   Within 24 hours of collection, all cores were vertically extruded and sectioned into 1-cm intervals at the USGS SPCMSC. The outer circumference of each interval was removed to avoid use of sediment that was in contact with the polycarbonate barrel. Each sediment interval was bagged and homogenized. Select intervals were immediately subsampled by scientist from the Florida Fish and Wildlife Conservation Commission for Pyrodinium bahamense cyst abundance (Lopez, unpublished data). Cores TB02M(B) and TB02M(C) were sectioned into 1-cm intervals to a depth of five centimeters as they were collected for the purpose of examining spatial variability in the uppermost section of the sediment column. The remainder of the two cores were not sampled. Person who carried out this activity:
   

   U.S. Geological Survey St. Petersburg Coastal and Marine Science Center

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Date: 2016 (process 3 of 8)

   In the laboratory, a subsample of each 1-cm interval was processed for basic sediment characteristics. Water content, porosity and dry bulk density were determined using water mass lost during drying. For each 1-cm interval, 34–90 milliliters (mL) of each wet subsample was packed into a graduated syringe with 0.5 mL resolution. The wet sediment was then extracted into a pre-weighed aluminum tray and the weight of the wet sediment and the volume was recorded. The wet sediment and tray were placed in a drying oven for a minimum of 48 hours at 60 degrees Celsius (°C). Water content (?) was determined as the mass of water (mass lost when dried) relative to the initial wet sediment mass. Dry bulk density was determined by ratio of dry sediment to the known volume of sediment packed into the syringe. Porosity was calculated from the equation ? = ? / [?+(1-?)/?s] where ?s is grain density assumed to be 2.5 grams per cubic centimeter (g/cm^3). Salt-mass contributions were removed based on the salinity measured at the time of sample collection. Water content, porosity and dry bulk density are reported in the Excel spreadsheet. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
   

   U.S. Geological Survey St. Petersburg Coastal and Marine Science Center

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Data sources produced in this process:

   • 16FWR05_SedimentPhysicalProperties.zip
   • 16FWR05_DataPlots.pdf

   Date: 2016 (process 4 of 8)

   Organic matter content was determined with a mass loss technique, referred to as loss on ignition (LOI). The dry sediment from the previous process was homogenized with a porcelain mortar and pestle. The dried sediment (2-5 grams) was placed into a pre-weighed porcelain crucible. The mass of the dried sediment was recorded. The sample was then placed inside a laboratory muffle furnace with stabilizing temperature control. The furnace was heated to 110°C for a minimum of 6 hours to remove hygroscopic water absorbed onto the sediment particles. The furnace temperature was then lowered to 60 °C, at which point the sediments could be reweighed. The dried sediment was returned to the muffle furnace. The furnace was heated to 550 °C over 30 minutes and kept at 550 °C for 6 hours. The furnace temperature was then lowered to 60 °C, and held at this temperature until the sediments could be reweighed. The latter step prevents the absorption of moisture, which can affect the measurement. The mass lost during the 6 hour baking period relative to the 110 °C-dried mass is used as a metric of organic matter content. Data are reported as a ratio of mass (g) of organic matter to mass (g) of dry sediment (post-110 °C drying). Replicate analyses of loss on ignition are reported for quality assurance in the Excel spreadsheet. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
   

   U.S. Geological Survey St. Petersburg Coastal and Marine Science Center

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Data sources produced in this process:

   • 16FWR05_SedimentPhysicalProperties.zip
   • 16FWR05_DataPlots.pdf

   Date: 2016 (process 5 of 8)

   Prior to particle size analysis, organic material was chemically removed for the samples using 30% hydrogen peroxide (H2O2). Wet sediment was dissolved in H2O2 overnight. The H2O2 was then evaporated and the sediment washed and centrifuged twice with deionized water. Grain size analyses were completed on all sediment intervals from the surface to a maximum depth of 10 cm, or the maximum depth interval for the core is less than 10 cm. Grain size analyses on the sediment cores were performed using a Coulter LS13 320 (https://www.beckmancoulter.com/) particle-size analyzer, which uses laser diffraction to measure the size distribution of sediments ranging in size from 0.4 microns to 2 millimeters (mm) (clay to very coarse-grained sand). To prevent shell fragments from damaging the Coulter instrument, particles greater than 1 mm in diameter were separated from all samples prior to analysis using a number 18 (1000 microns or 1 mm) U.S. standard sieve, which meets the American Society for Testing and Materials (ASTM) E11 standard specifications for determining particle size using woven-wire test sieves. Two subsamples from each depth interval were processed through the instrument a minimum of four runs each. The sediment slurry was sonicated with a wand sonicator for 1 minute before being introduced into the Coulter LS13 320 to breakdown aggregated particles. The LS13 320 measures the particle-size distribution of each sample by passing sediment suspended in solution between two narrow panes of glass in front of a laser. Light is scattered by the particles into characteristic refraction patterns measured by an array of photodetectors as intensity per unit area and recorded as relative volume for 92 size-related channels (bins). The size-classification boundaries for each bin were specified based on the ASTM E11 standard. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Date: 2016 (process 6 of 8)

   The raw grain size data were then run through the free software program GRADISTAT (Blott and Pye, 2001; http://www.kpal.co.uk/gradistat), which calculates the mean, sorting, skewness, and kurtosis of each sample geometrically in metric units and logarithmically in phi units method. GRADISTAT also calculates the fraction of sediment from each sample by size category (for example, clay, coarse silt, fine sand). A macro function in Microsoft Excel, developed by the USGS SPCMSC, was applied to the data to calculate average and standard deviation for each sample set (8 runs per sample), and highlight runs that varied from the set average by more than ±1.5 standard deviations. Excessive deviations from the mean are likely the result of equipment error or extraneous organic material in the sample and are not considered representative of the sample. The highlighted runs were removed from the results and the sample average was recalculated using the remaining runs. The averaged results for all samples, including the number of averaged runs and the standard deviation of the averaged results were summarized in an of Excel workbook with each core on its own tab. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Data sources produced in this process:

   • 16FWR05_GrainSize.zip
   • 16FWR05_DataPlots.pdf

   Date: 2016 (process 7 of 8)

   Dried ground sediment from the uppermost five 1-cm intervals of each core were used for the detection of radionuclides by standard gamma-ray spectrometry (Cutshall and Larsen, 1986) at the USGS St. Petersburg radioisotope lab. The sediments (10-50 g) were sealed in airtight polypropylene containers. The sample weights and counting container geometries were matched to pre-determined calibration standards. The sealed samples sat for a minimum of 3 weeks to allow Ra-226 to come into secular equilibrium with its daughter isotopes Pb-214 and Bi-214. The sealed samples were then counted for 24-48 hours on a planar-style, low energy, high-purity germanium, gamma-ray spectrometer. The suite of naturally-occurring and anthropogenic radioisotopes measured along with their corresponding photopeak energies in kiloelectron volts (keV) are Pb-210 (46.5 keV), Th-234 (63.3 keV), Pb-214 (295.7 and 352.5 keV; proxies for Ra-226), Be-7 (477.6 keV), Bi-214 (609.3 keV; proxy for Ra-226), Cs-137 (661.6 keV), and K-40 (1640.8 keV). Sample count rates were corrected for detector efficiency determined with International Atomic Energy Agency RGU-1 reference material, standard photopeak intensity, and self-absorption using a U-238 sealed source (Cutshall and others, 1983). All activities were decay-corrected to the date of field collection. The radioisotopic activities reported in the Excel spreadsheet include the counting error for all samples. The critical level is reported for the sample set. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
   

   U.S. Geological Survey St. Petersburg Coastal and Marine Science Center

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   mmarot@usgs.gov

   Data sources produced in this process:

   • 16FWR05_GammaSpectroscopy.zip
   • 16FWR05_DataPlots.pdf

   Date: 13-Oct-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?
   Blott, S.J. and Pye, K., 2001, Gradistat: A grain size distribution and statistics package for the analysis of unconsolidated sediments: Earth Surface Processes and Landforms Volume 26.

   Online Links:

   • http://www.kpal.co.uk/gradistat.html

   Other_Citation_Details: Pages 1237-1248
   

   Cutshall, N.H., Larsen, I.L., and Olsen, C.R., 1983, Direct analysis of 210Pb in sediment samples: self-absorption corrections: Nuclear Instruments and Methods Volume 206.

   Online Links:

   • https://doi.org/10.1016/0167-5087(83)91273-5

   Other_Citation_Details: Pages 309-312
   

   Cutshall, N.H. and Larsen, I.L., 1986, Calibration of a portable intrinsic Ge gamma-ray detector using point sources and testing for field applications: Health Physics Volume 51.

   Online Links:

   • https://doi.org/10.1097/00004032-198607000-00004

   Other_Citation_Details: Pages 53-59
   

   Lopez, C.B., Smith, C.G., Marot, M.E., Karlen, D.J, and Corcoran, A.A., 2015, The role of seedbeds in Pyrodinium bahamense bloom dynamics in Tampa Bay: Proceedings, Tampa Bay Area Scientific Information Symposium BASIS 6.

   Online Links:

   • https://www.tbeptech.org/BASIS/BASIS6/BASIS6_Proceedings_FINAL.pdf

   Other_Citation_Details: Pages 78-83
   

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

1. How well have the observations been checked?
   The positional accuracy of the sample locations was determined by the accuracy of the Garmin GSPMAP 1040xs vessel-mounted Global Positioning System (GPS) receiver used to record the sample sites during the time of collection. Replicate analyses of loss on ignition are reported for quality assurance. The grain size data represent the sample averages for a subset of the statistical parameters calculated by GRADISTAT. The number of runs included in the averaged results are reported, and the standard deviation of the averaged results are reported for most parameters. The gamma spectroscopic radioisotope activities reported include the counting error for all samples. The critical level for gamma spectroscopy is reported for each core set.
2. How accurate are the geographic locations?
   Sample locations were recorded at the time of collection using a Garmin GPSMAP 1040xs vessel-mounted GPS receiver located amidship of the 25-foot R/V Halimeda. The actual core sites were offset from the center of the boat by up to 10 feet.
3. How accurate are the heights or depths?
   Surface elevations of the sediment cores were determined as depth below water level.
4. Where are the gaps in the data? What is missing?
   The data release doi:10.5066/F7K64G99 associated with this metadata includes the geographic location, field notes, water column physical parameters, sediment physical properties, grain size, and sediment radiochemistry for six cores collected at three sites in Old Tampa Bay, Florida.
5. How consistent are the relationships among the observations, including topology?
   The grain-size sample runs in the GRADISTAT output files for which the mean Folk and Ward grain size varied from the set average by more than 1.5 standard deviations are highlighted in yellow and were not included in final averaged results. No formal logical accuracy tests were conducted on the remaining datasets.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: None
Use_Constraints:

The U.S. Geological Survey requests that it be acknowledged as the originator of this dataset in any future products or research derived from these data.

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

   Attn: Marci E. Marot

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   mmarot@usgs.gov
2. What's the catalog number I need to order this data set? Downloadable data
3. What legal disclaimers am I supposed to read?

   This publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:

     This zip archive includes Microsoft Excel spreadsheets, comma-separated values text files, Portable Document Format (PDF) image files, and accompanying metadata for sediment data from cores collected from Old Tampa Bay, Florida (USGS FAN 2016-327-FA). in format Compressed (zip) archive Multimedia presentation

     Network links:

     https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_FieldLogs.pdf https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_SiteLocations.zip https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_CTDProfiles.zip https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_SedimentPhysicalProperties.zip https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_GrainSize.zip https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_GammaSpectroscopy.zip https://coastal.er.usgs.gov/data-release/doi-F7K64G99/data/16FWR05/16FWR05_DataPlots.pdf

   • Cost to order the data: None, if obtained online

5. What hardware or software do I need in order to use the data set?

   The data tables for USGS FAN 2016-327-FA were created in Microsoft Excel 2010 and can be opened using Microsoft Excel 2007 or higher; these data may also be viewed using the free Microsoft Excel Viewer (http://office.microsoft.com/). The data tables are also provided as comma-separated values text files (.csv). The .csv data file contains the tabular data in plain text and may be viewed with a standard text editor. Portable Document Format (PDF) files can be viewed using the free software Adobe Acrobat Reader (http://get.adobe.com/reader).

Who wrote the metadata?

Dates:

Last modified: 13-Oct-2020

Metadata author:

U.S. Geological Survey

Attn: Marci E. Marot

Geologist

600 4th Street South

St. Petersburg, FL

USA

727-502-8000 (voice)

mmarot@usgs.gov

Metadata standard:

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