Accessing Hunter-Gatherer site structures using Fourier transform infrared spectroscopy: applications at a Taltheilei settlement in the Canadian Sub-Arctic Don H. Butler * , Peter C. Dawson Department of Archaeology, University of Calgary, 2500 University Dr. N.W., Calgary, Alberta T2N 1N4, Canada article info Article history: Received 7 August 2012 Received in revised form 22 October 2012 Accepted 24 November 2012 Keywords: FTIR Hunter-gatherers Site structure Canada Hearths Bone burning Calcite Carbonate hydroxylapatite Authigenic phosphates Crystallinity index Carbonate/phosphate ratio abstract The results of Fourier transform infrared spectroscopy on soils and caribou bone from a Taltheilei culture settlement in northern Canada contribute to developing micro-archaeological approaches suitable for locating and characterizing hearth and midden features on hunter-gatherer sites. A weak yet pervasive signal for montgomeryite was developed from the diagenesis of dispersed ash and caribou processing residues. Disordered calcite, carbonate hydroxylapatite, charcoal, and burned bone in two pit-house hearth deposits indicate that both wood and bone were used for fuel. Crystallinity indices and carbonate/phosphate ratios for bone indicate high intensity burning. These data, in tandem with the presence of semi-subterranean dwellings, demonstrate that this particular tundra-based encampment was occupied during cold seasons, a type of settlement behaviour previously unrecognized in the Taltheilei archaeological record. Our results confirm that Fourier transform infrared spectroscopy is an accessible, rapid, and cost effective means of discovering micro-archaeological evidence valuable for reconstructing hunter-gatherer site structures. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction 1.1. Objectives The archaeological record of Taltheilei caribou hunters (ca. 600 B.C.eA.D. 1700) is gradually being uncovered in southern Nunavut and northern Manitoba, Canada (Gordon, 1975, 1996; Nash, 1970; Petch, 1992; Petch et al., 1997). Taltheilei sites in the region are generally lithic scatters, stone markers, or small sites with low artefact densities that are interpreted as ephemeral camps (Schwimmer et al., 1998). Recent surveys and excavations in southern Nunavut have discovered new evidence documenting Taltheilei land-use, specifically the extended cold season use of tundra-based pit-house settlements (Dawson et al., 2009; Hodgetts et al., 2011). These sites provide unique opportunities to document the use and organization of space at the settlement scale. Locating and characterizing hearth and refuse disposal areas, in particular, are fundamental to accurately reconstructing space at hunter- gatherer settlements (Binford, 1983; Oswald, 1984). Centring on the micro-archaeological record at the Ikirahak settlement (JjKs-7) in southern Nunavut, this research uses Fourier transform infrared spectroscopic (FTIR) analyses of soils and caribou bone to charac- terize dwelling hearth features and to locate outdoor hearths and bone middens. We aim to determine the use of space at the site and clarify its season of occupation, which will contribute both to addressing issues with our understanding of Taltheilei settlemente subsistence patterns and to developing micro-archaeological approaches suitable for defining hunter-gatherer site structures. Frequencies, sizes, and locations of hearth and midden features are useful for reconstructing dynamics in site functions, seasons of occupation, mobility patterns, and socio-economics. The types of materials used for fuel can provide evidence for seasonality, while multiple overlapping hearths act as a record of reoccupation (Bamforth et al., 2005; Schiegl et al., 2003). Similarly, numerous large middens are common at long-term camp sites and at sites with long histories of reoccupation. Shorter term camps tend to develop a light layer of homogenously dispersed refuse (Kent, 1999). Smaller middens situated adjacent to dwellings typically represent household work and refuse disposal, while larger middens in central and peripheral areas can relate to communal activities (Beck and Hill, 2004; Oetelaar, 1993). * Corresponding author. Tel.: þ1 403 478 6739; fax: þ1 403 282 9567. E-mail address: dhbutler@ucalgary.ca (D.H. Butler). Contents lists available at SciVerse ScienceDirect Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas 0305-4403/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jas.2012.11.015 Journal of Archaeological Science 40 (2013) 1731e1742