Bone Weathering in a Periglacial Environment: The Tayara Site (KbFk-7), Qikirtaq Island, Nunavik (Canada)

Abstract

ABSTRACT. Bone weathering analysis of the Palaeoeskimo Tayara site (Qikirtaq Island, Nunavik, Canada) documents site taphonomy in the Arctic periglacial environment. Like a majority of sites in the eastern Canadian Arctic, Tayara has a faunal assemblage dominated by marine mammals (seal, walrus, and beluga whale) and some terrestrial mammals (caribou, fox, and bear). Statistical and spatial analyses of five weathering stages reveal that large mammal bone preservation is generally good and does not seem to be influenced by taxonomic and skeletal differences. The good preservation of the faunal assemblage seems to have been favored by the burial of bones and their incorporation into the active layer, which suggests only limited mechanical deterioration (i.e., freeze-thaw or wet-dry cycles, or both) before or at the time of burial. Burial depth partly explains the degree of bone weathering. Indeed, the well-preserved bones are found mainly where burial is associated with thicker overlying sediments. This implies rapid bone burial with a low degree of exposure to temperature changes and atmospheric processes. However, analysis also shows the presence of highly weathered bones where burial is associated with thicker overlying sediments. Consequently, differential bone depth probably does not explain all bone-weathering variability within the site. These results show the importance of examining bone weathering before any archaeozoological and paleoethnographic interpretations.Key words: bone weathering, taphonomy, large mammals, periglacial environment, spatial analysis, Palaeoeskimo RÉSUMÉ. L'analyse méthodique de la météorisation osseuse des restes fauniques du site paléoesquimau de Tayara (île Qikirtaq, Nunavik, Canada) documente la taphonomie d'un site archéologique en contexte périglaciaire arctique. Comme dans la plupart des sites arctiques de l'Est canadien, l'assemblage faunique de Tayara est dominé par des mammifères marins (phoque, morse et béluga) plus quelques mammifères terrestres (caribou, renard et ours). Les analyses statistiques et spatiales selon cinq stades d'altération reconnus montrent une bonne conservation des restes osseux des grands vertébrés, qui ne semble pas être influencée par les différences taxonomiques et squelettiques. La bonne conservation de l'assemblage osseux semble avoir été favorisée par l'enfouissement des ossements et leur incorporation dans la couche active. Ceci suggère une détérioration mécanique pré-et synenfouissement limitée (i.e., cycles gel-dégel et/ou d'hydratation-dessiccation). La profondeur d'enfouissement explique en partie le degré de préservation des ossements. En effet, les ossements les mieux conservés se rencontrent principalement dans les zones où les sédiments de recouvrement sont les plus épais. Ceci implique un enfouissement rapide ainsi qu'un faible degré d'exposition des ossements aux changements de température et aux processus atmosphériques. Les analyses montrent aussi la présence de quelques os fortement détériorés situés dans les zones où les sédimen...

The Micro‐Taphonomy of Cold: Differential Microcracking in Response to Experimental Cold‐Stresses

“…Macroscopic cracking damage to the bone segments was rare, with only a single incident observed in the freeze‐dried treatment group. This observation was consistent with previous case studies that found that freeze‐thawing cycles could produce macroscopic longitudinal cracks on bone . However, this was an isolated observation, suggesting that macroscopic damage would be a rare effect of cold exposure (2% of long bone segments).…”

Comparing fill and floor: A taphonomic framework for understanding depositional histories in a semi‐subterranean house in north‐west Alaska

“…The higher frequency of weathering on bones in the fill layer suggests fill material was exposed for longer periods than floor material. Despite the fact that there is very little actualistic or taphonomic research about the effects of root etching on faunal material (Denys, ; Lyman, ), it is most often seen on bones from shallow buried assemblages, where they are in the active root zone (Betts, ; O'Connor, ; Todisco & Monchot, ).…”

“…The lack of root etching on bones from the fill layers may indicate that burial for most of the assemblage was sufficiently rapid to remove them from the active root zone (Todisco & Monchot, ). Based on the evidence that some of the bones were weathered (<6.5%), it is likely that the fill material was exposed to the elements for a longer time than the floor material.…”

“…Although all microenvironments are different (Sutcliffe, ), the more frequent freeze–thaw cycles in the active layers of the fill likely led to a higher frequency of fragmentation of mammal and bird bones and decreased the frequency of identifiable bones (Guadelli, ; Ping et al, ). The effect of freeze–thaw cycles on archaeological assemblages has seen limited research, with most studies focusing on movement and cryoturbation, especially of artefacts (Carr, ; Denys, ; Goebel et al, ; Hilton, ; Masson, ; Matthiesen, Jensen, Gregory, Hollesen, & Elberling, ; Milne, ; Todisco & Monchot, ). A study by Guadelli () showed that over the course of hundreds of freeze–thaw cycles, bones and teeth can be rendered unidentifiable.…”

Identification of a possible engraved Venus from Předmostí, Czech Republic

“…On the medullary face, this process engendered the almost complete disappearance of the spongy bone, the digging of cupules caused by a localized chemical attack and the opening of fine longitudinal cracks typical of bone exposed to the action of meteorological and weathering agents (Behrensmeyer, 1978;Lyman and Fox, 1989;Lyman, 1992;Tappen, 1994). Such modifications are common in periglacial environments (Todd and Frison, 1986;Todisco and Monchot, 2008).…”