Author(s): Linda Scott Cummings

Year: 2019


In Minnesota, understanding ceramic periods of prehistory and their attendant subsistence practices is of critical importance. Our previous study (Scott Cummings 2017) indicates that problems with radiocarbon dates on ceramics are not unique to this period. Instead, the entire prehistoric record is affected. The natural Minnesota landscape contributes dissolved inorganic carbon (DIC) and organic carbon (DOC), confounding efforts to create a clean radiocarbon record. When graphing all dates from Minnesota the oldest dates are on bones. This trend generally holds true whether investigating individual sites with multiple dates, cultures, or regions of the state. This is particularly obvious when examining the dates on bones obtained from stratigraphic deposits at LaMoille (21WN1). At that site dates on both bone collagen and burned bone appear to be too old. Therefore, one of the first steps involved in evaluating bone ages is to date calcined bones to compare with the previously-obtained dates on bone collagen and burned bones at LaMoille. In addition, modern reference bones, other body parts, and aquatic plants, as well as sediment, were dated to observe any offsets present. Specifically, catfish, aquatic plant, aquatic grass, and lake sediment, all from Albert Lea Lake, were examined as reference material. Animal bones from modern populations include two bison samples (one vertebra and one horn core), muskrat bones from three lakes, and bones of “known” age from historic deposits at Historic Fort Snelling (21HE99) that included a human phalanx from a ca. 1904 fill and a bison bone from a latrine deposit expected to represent AD 1825–1835. This expands the efforts examining reference samples (fish and wild rice) as part of the previous study (Scott Cummings 2017) that produced dates offset from the time of collection.

Given the previously identified anomalies, additional samples were submitted to answer specific questions on a site-by-site basis. Six archaeological sites including Historic Fort Snelling, LaMoille, Blazing Star Shore (21FE76), the Preece Site (21BL26), the Crace Site (21ML3), and the Wilford Site (21ML12) had curated remains that were submitted for this study. These populations of modern materials and archaeological sites are discussed separately below. The unifying theme to this study is pursuit of information concerning recovery of concurrent or discrepant dates from stratigraphic or feature proveniences where more than one type of material was available to date. When possible, radiocarbon ages were obtained for short-lived botanics, charcoal, bones, and charred food crust from archaeological settings. Expansion of the radiocarbon database to include dates on this variety of remains is the first step in creating better site and regional chronologies.

Cite this Record

ORGANIC RESIDUE (FTIR) ANALYSIS, BONE COLLAGEN EXTRACTION, AND AMS RADIOCARBON AGE DETERMINATION ON SAMPLES FROM SITES 21HE99, 21FE76, 21BL26, AND 21ML12, MINNESOTA. Linda Scott Cummings. PRI Technical Report ,2017-088/2018-057. 2019 ( tDAR id: 454706) ; doi:10.6067/XCV8454706

This Resource is Part of the Following Collections

Spatial Coverage

min long: -97.515; min lat: 43.351 ; max long: -89.429; max lat: 49.004 ;

Individual & Institutional Roles

Contact(s): PaleoResearch Institute

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18-057_Report.pdf 3.54mb Aug 9, 2019 2:12:05 PM Public