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Description of Database Attributes and Values (organized alphabetically)
(from Taylor and Batterson, 2001 and Batterson, pers. comm)

¹⁴C Date and Associated Error (C14_Date, Pos, Neg):
This column reports radiocarbon age BP, corrected for isotopic fractionation with respect to the D13Cpermil (see below). The sample date is reported as radiocarbon years before present (BP). This is not equivalent to a calibrated calendar age. The radiocarbon ages in the database range from modern to greater than 40,000 BP, with most occurring between 1,000–14,000 BP. The upper limit of radiocarbon dating is typically about 60,000 BP.

All dates have an associated error factor which results from uncertainty related to variability in the production of radioactive isotopes over time. The date is therefore given as a time interval. Database fields Pos and Neg report the “plus” and “minus” error bars for the radiocarbon age, respectively, and are also reported in radiocarbon years. The “true age” will lie within the upper and lower error ranges, with a certain probability. By general convention, the error range reports one standard deviation (i.e., there is a 68% probability that the true age lies within the time interval given). However, finite radiocarbon dates from the GSC were reported to within 2 standard deviations and may be rounded to between 1 and 3 significant figures (see e.g., McNeeley, 2006). Infinite ages (those with no upper limit, e.g., greater than 34,000 yr BP) from the GSC were reported within 4 standard deviations.

δ¹³C (D13Cpermil):
This is the isotopic composition of the sample being measured. It represents the parts per thousand difference (‰) between the sample ¹³C content and the ¹³C content of the carbonate in the international Vienna Pee Dee Belemnite (VPDB) . VPDB refers to the Cretaceous belemnite formation at Pee Dee in South Carolina, USA. Most ¹⁴C samples show δ¹³C values about -25 ‰, and by convention this is the value to which the measured isotopic rations are normalized. Historically, the GSC took a somewhat different approach: for marine shells, GSC samples were corrected to δ¹³C = 0 ‰ PDB and then normalized to δ¹³C = -25 ‰. This means that GSC dates are about 410 years younger than would be reported from the same sample by another laboratory. For comparative purposes it is recommended that 410 years be added to GSC ages and the error converted to 1 standard deviation (Miller et al., 1988).
e = estimated
m = measured

Collector:
This is the name of the sample collector.

Elevation:
Elevation of the sample collection, generally either metres above or below sea level (negative sign). For lake sediment samples (e.g., gyttja) lake surface elevation is given.

Laboratory Number (LabNum):
This is a unique ID assigned to each database sample that comprises an analytical laboratory identifier, followed by the sample number (e.g., GSC-4211). The following is a list of laboratory codes:

   AA       Arizona Accelerator Facility
   Beta     Beta Analytical, Florida
   B        Bern, Switzerland
   BGS      Brock University, Geological Sciences
   CAMS     Center for Accelerator Mass Spectrometry, USA
   DAL      Dalhousie University, Halifax
   DIC      Dicarb Radioisotope Company, Florida
   GAK      Gakushuin University, Japan
   GSC      Geological Survey of Canada, Ottawa
   GX       Geochron Laboratories, Massachusetts
   I        Teledyne Isotopes, New Jersey
   L        Lamont, New York
   N        Nishina Memorial, Japan
   P        Pennsylvania
   Q        Godwin Laboratories, Cambridge
   S        Saskatchewan Research Council
   SI       Smithsonian Institution, Washington
   SM       Mobil Oil Corporation, Dallas, USA
   St       Stockholm, Sweden
   T        Trondheim, Norway
   TO       Isotrace Laboratory, University of Toronto
   UGa      University of Georgia, USA
   UQ       Universite de Quebec à Montreal
   WAT      University of Waterloo
   Y        Yale University

Location:
Sample collection locations are provided as both latitude/longitude and UTM (easting, northing, zone) coordinates. All coordinates are based on the 1927 North American Datum (NAD27).

Locality:
Locality refers to the named community, lake or pond closest to where the sample was taken.

Material:
The database includes reported ages for a wide range of materials, including: terrestrial and marine shells and foraminifera; terrestrial and marine macrofauna remains (e.g., bone, charred fat); terrestrial vegetation and charcoal; peat, detritus, and turf; and sediments including gyttja (total organics), clay, and muds.

The reliability of ages varies with type of sample material, biological or other isotopic fractionation in the environment, reservoir effects, post-depositional processes, and contamination (often by groundwater). Improvements in the techniques and calibration curves may also influence age reliability. Reported ages should be evaluated by the user for appropriateness to address the question at hand.

Reference:
This column reports the source from which the sample age was obtained. Most dates are from the Geological Survey of Canada (GSC) laboratory, and are listed in the radiocarbon date list published yearly by the GSC. However, if the dates are used in an alternate publication, that publication is listed in the reference column. Refer to the References/Sources list below for complete citations.

Uncorrected Age (Uncor_age):
This is the calculated age of the sample before it was normalized to the VPDB standard ("Vienna Pee Dee Belemnite").

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DISCLAIMER

Open File reports, maps and digital data issued by the Geological Survey Division of the Mining and Mineral Development Branch, Government of Newfoundland and Labrador, are made available for public use. They have not been formally edited or peer reviewed, and are based upon preliminary data and evaluation.  The user agrees not to provide a digital reproduction or copy of this product to a third party. Derivative products should acknowledge the source of the data.

The Geological Survey, a division of the Mining and Mineral Development Branch, Government of Newfoundland and Labrador (the "authors and publishers"), retains the sole right to the original data and information found in any product produced. The authors and publishers assume no legal liability or responsibility for any alterations, changes or misrepresentations made by third parties with respect to these products or the original data. Furthermore, the Geological Survey assumes no liability with respect to digital reproductions or copies of original products or for derivative products made by third parties. Please consult with the Geological Survey in order to ensure originality and correctness of data and/or products.

RECOMMENDED CITATION
(for downloaded database)

Newfoundland and Labrador Geological Survey. "Radiocarbon Dates." Newfoundland and Labrador GeoScience Atlas OnLine. Last update: [check the What's New file]. https://geoatlas.gov.nl.ca [fill in date downloaded].

The original source should be referenced wherever possible. Please refer to the Source citations below or the Geofiles, to search for the pertinent reports and maps. The 'Last Update' refers to the last time the database information was updated and does not refer to cosmetic changes to the database.

REFERENCES/SOURCES

Compilation:
Taylor, D.M., and Batterson, M.J.

2001: Carbon-14 date list for Newfoundland and Labrador.  Newfoundland Department of Mines and Energy, Geological Survey, Open File NFLD/2190, version 2. (pdf - 200kb)

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