e-mail: dweis@eoas.ubc.ca
phone / tél.: 1-604-822.1697
mobile: 778-386.4466

Archaeological Science

Detailed written records only exist for a very small amount of human history. Researchers must therefore combine Indigenous traditional knowledge with scientific evidence, often collected with geochemical and spectroscopic techniques, to investigate ancient human biology, behaviour, and culture.

However, acquiring meaningful scientific information about rare and culturally sensitive materials without destroying or modifying them is extremely challenging. Research must adapt and develop analytical frameworks for appropriately acquiring key data from archaeological biominerals and mineraloids to address the fundamental question:

“What was the original context and condition of the archaeological materials we find?”

Obsidian-mtn-chip
Left: In-situ obsidian flow (black layer) from the central coast of British Columbia (photo: R. McMillan). Right: A naturally fractured fragment of obsidian (photo: D. Cullon).

Since 2014, Dominique has been involved in archaeological research that uses unique and robust scientific techniques and data to support investigations of ancient human history while minimizing the destruction and alteration of valuable archaeological materials and contexts.

The work has focused on the trace element, structural, and isotopic characteristics of ancient biominerals (“bones”) and mineraloids (“stones”). Research was conducted with graduate student Rhy McMillan (PhD, graduated 2020; EOAS).

In studying archaeological bone, Rhy has evaluated stratigraphic provenance, and thus the age of megafauna and Neandertal bones at Scladina Cave (Belgium; McMillan et al., 2017). Rhy, Dominique and collaborators in Beligium (P. Claeys and C. Snoeck at VUB) have also assessed the taphonomic state of archaeological bones and the effectiveness of acetic acid pre-treatment procedure used to remove diagenetic alteration (McMillan et al., 2019a).

In studying archaeological “stone,” the team has focussed on enhancing the traditional techniques for sourcing obsidian (volcanic glass) stone tools in British Columbia (McMillan et al., 2019b), taking advantage of PCIGR’s geochemical studies of the Garibaldi Volcanic Belt and the High Cascades. The team has applied this approach to a suite of rare archaeological belongings in partnership with xʷməθkʷəy̓əm (Musqueam), an Indigenous community near Vancouver (McMillan et al., 2019c). The archaeological research in this region was initiated via the UBC Indigenous/Science Research Excellence Cluster.

Some aspects of the obsidian research are exemplified below.

Obsidian-point
Obsidian fractured by ancient people into a “point”. This belonging has been analyzed with split stream laser ablation ICP-MS (SS-LA-ICP-MS). Based on geochemical data (see next figure), the obsidian is likely from Mount Edziza, British Columbia (McMillan et al., 2019b).
Zr/Rb and Nb/Y of obsidian source materials in British Columbia. Circle markers in represent analyses of geologic materials with portable X-ray fluorescence, and square markers represent analyses of geologic materials with SS-LA-ICP-MS (McMillan et al., 2019b).
volcano-locations-obsidian
Volcano locations (coloured stars) and 207Pb/206Pb of geologic obsidian samples plotted geographically in British Columbia. Square markers are averages of SS-LA-ICP-MS analyses and associated error bars are 2 standard deviations (2SD) external uncertainty. Circle markers indicate multicollector ICP-MS analyses, for which 2SD error bars are smaller than the markers plotted (McMillan et al., 2019b).

Further Reading:

McMillan, R. (2020) Micro-analytical geochemical and spectroscopic investigations of the original context and condition of archaeological biominerals and mineraloids. Unpublished PhD dissertation, University of British Columbia, Vancouver, 461 p.

McMillan et al. (2019a) Evaluating the impact of acetic acid chemical pre-treatment on ‘old’ and cremated bone with the ‘Perio-spot’ technique and ‘Perios-endos’ profiles. Palaeogeography, Palaeoclimatology, Palaeoecology, 530: 330–344.

McMillan et al. (2019b) Splitting Obsidian: Assessing a multiproxy approach for sourcing obsidian artifacts in British Columbia. Journal of Archaeological Science: Reports, 28: 102040.

McMillan et al. (2017) Identifying the reworking and stratigraphic provenance of bones by exploring multivariate geochemical relationships with the “Perio-spot” technique. Journal of Archaeological Science, 88: 1–13.