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Comparative Archaeology Database, University of Pittsburgh
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The Central Alaska Peninsula Radiocarbon Dataset |
The data files SUMMARY.TXT and SUMMARY.XLS provide age estimates for specimens collected from cultural contexts in the Chignik-Meshik Rivers Region Cultural Resource Reconnaissance Project. SUMMARY.TXT is a comma delimited ASCII text file; SUMMARY.XLS contains the same data in the form of an Excel spreadsheet. Each line in the ASCII file corresponds to one radio carbon sample. There are 75 lines, each with 12 variables separated by commas. The variables are listed in the following order:
| 1 | Site number. Formal naming conventions for archaeological sites in the state of Alaska. |
| 2 | Region. Geographic location of the archaeological site. |
| 3 | Material. Type of organic material measured by accelerator mass spectometry. |
| 4 | Sample taxon. Taxonomic name for the carbonized organic material measured by accelerator mass spectometry. |
| 5 | δ13C. Stable carbon isotope ratio measure and reported by each lab. |
| 6 | Lab no. Name/number given to each radiocarbon measurement by each lab. |
| 7 | Conventional age estimate in radiocarbon years before present (rcybp). |
| 8 | Instrumental measurement error expresed as +/- radiocarbon years. |
| 9 | 2σ calBP-. Lower (older) age of the 95.4% probability calibrated BP age range from OxCal. |
| 10 | 2σ calBP+. Upper (younger) age of the 95.4% probability calibrated BP age range from OxCal. |
| 11 | 2σ calBP median. Median age of the 95.4% probability calibrated BP age range from OxCal. |
| 12 | Field report. Project field report that describes the context of the measured sample. |
The first line of the ASCII text file, for example, looks like this:
CHK-104,Chignik Drainage - Alec River,charcoal,Salix/Populus,-27.1,Beta-312530,1160,30,1177,983,1080,Shirar etal 2012
This means that the formal designation for the archaeological site is “CHK-104”; the site is found in a geographic area called “Chignik Drainage – Alec River”; the material analyzed by AMS was “charcoal”; the plant the charcoal came from was identified as “Salix/Populus”; the stable carbon isotope ratio measured by the AMS lab was “-27.1”; the name given to the measured sample by the lab is “Beta-312530”; the conventional age estimate is “1160” years before AD 1950; the instrumental error of this measurement is “30” radiocarbon years; the lower (older) age of the 95.4% calibrated probability range (as determined by OxCal) is “1177” calendar years before AD 1950; the upper (younger) age of the 95.4% calibrated probability range (as determined by OxCal) is “983” calendar years before AD 1950; the median age of the 95.4% calibrated probability range (as determined by OxCal) is “1080” calendar years before AD 1950; the context from which the sample came is detailed in a field report entitled, “Shirar etal 2012”.
The last, or 75th line of the ASCII text file is:
CHK-133,Ocean River Drainage,charcoal,Salix,-24.9,UGAMS-12814,417,23,518,337,493,Shirar etal 2013
This means that the formal designation for the archaeological site is “CHK-133”; the site is found in a geographic area called “Ocean River Drainage”; the material analyzed by AMS was “charcoal”; the plant the charcoal came from was identified as “Salix”; the stable carbon isotope ratio measured by the AMS lab was “-24.9”; the name given to the measured sample by the lab is “UGAMS-12814”; the conventional age estimate is “417” years before AD 1950; the instrumental error of this measurement is “23” radiocarbon years; the lower (older) age of the 95.4% calibrated probability range (as determined by OxCal) is “518” calendar years before AD 1950; the upper (younger) age of the 95.4% calibrated probability range (as determined by OxCal) is “337” calendar years before AD 1950; the median age of the 95.4% calibrated probability range (as determined by OxCal) is “493” calendar years before AD 1950; the context from which the sample came is detailed in a field report entitled, “Shirar etal 2013”.
Download the file SUMMARY.TXT (9 KB) or the file SUMMARY.XLS (39 KB).