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Appendix A. Description of Methods Employed
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149 appendix a Description of Methods Employed Ceramic Residue Sampling and Other Organic Sampling Methods Our decision to obtain absolute dates on previously undated archaeological sites resulted in the use of two related sets of procedures, one considered standard, and one of increasingly accepted utility and use. Standard or conventional 14C dating is an established procedure that we employed at two locations, the Camp Miniwanca site and the Mt. McSauba site. Given that we had also sampled for OSL at both locations, this was an important comparative dating and calibration protocol for the project. At the Camp Miniwanca site we had the good fortune to obtain an exposure of an organic horizon with cultural material buried 20 meters below the crest of a large parabolic dune. The exposure revealed a hearth feature with abundant charcoal and associated ceramics. A large sample of charcoal was removed from the hearth profile with clean metal instruments and placed in several aluminum foil envelopes. The envelopes with the samples were opened and air-dried in a fume hood at the Michigan State University Consortium for Archaeological Research. A small sample of consolidated charcoal was removed for identification of wood species by Professors Catherine Yansa and Frank Telewski of Michigan State University; it is Picea sp. The charcoal samples were subsequently consolidated and repackaged for shipment to Beta Analytic for a standard or conventional 14C date. The Mt. McSauba site revealed a similar parabolic dune exposure with cultural material in association with a buried organic horizon. The organic horizon was buried under multiple meters of eolian sand, and contained preserved organic material, some carbonized and some not. Similar field procedures were used for sample collection. Since we were unsure when the sample might be submitted for dating, it was kept frozen at Michigan State University until its transmittal to Beta Analytic for dating. appendix a 150 Carbonized food residues on the interiors of ceramic vessels have increasingly been used for a variety of purposes including absolute dating of small samples (Lovis 1990b, 1990c) and various dietary analyses (Hart et al. 2003; Morton and Schwarcz 2004; Schulenburg 2002). The issue of reservoir effects, which may affect the accuracy of Accelerator Mass Spectrometer (AMS) dating, has been raised and systematically addressed particularly for the northeastern and midwestern United States (Hart and Lovis 2007a, 2007b). We employed AMS dating of carbonized residues at two previously undated archaeological locales, the Winter site (Richner 1973) and the Scott Point site. Both sites are deep and stratified, and three residue samples were obtained from ceramics at each site. We dated identifiable rim sherds from the upper and lower parts of the sequences at both locations using procedures outlined in Lovis (1990b, 384). Only diagnostic identifiable rim sherds were used, only interior residues were collected if they were horizontally oriented accretions attributable to food preparation, and all collection was performed with clean stainless steel implements, onto laboratory glass, and then packaged for transshipment to Beta Analytic in glass vials. All sample collection was performed at the Michigan State University Consortium for Archaeological Research. We were able to augment the chronology at the Winter site with an OSL sample underlying the cultural sequence, again providing control and calibration on the different dating techniques. All radiocarbon dates were calibrated with Calib v. 5.0.2 (Stuiver et al. 2006) employing IntCal04 (Reimer et al. 2004). All tests for contemporaneity and calculation of pooled means employing Ward’s Method were undertaken with Calib 5.0.2 subroutines. Results of absolute dating procedures are presented in appendix B. Conventions for Reporting the Ages of Samples from 14C and Optical (OSL) Dating Two different methods were used in this study and are commonly employed in the disciplines of geology, physical geography and archaeology. These dating techniques, however, are often used for different purposes and at different scales of resolution in each of the disciplines and, consequently, have different “meaning” to professionals in these fields. Although differences in the use and interpretation of dating methods across disciplines can be confusing enough, inconsistencies in reporting standards by each dating method lead to further misunderstandings. For example, the base year used for measurements of how old a sample is using 14C methods is a.d. 1950, and for OSL it is typically (but not always) a.d. 2000. To minimize such potential confusion, an overview of how OSL and 14C ages are typically reported is presented below. Additionally, the conventions for reporting, and the abbreviations for age notations used throughout...