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ABSTRACT Considered in isolation, the radiocarbon ( 14 C) dates on short-lived plant remains from the Jean-Baptiste Lainé (formerly Mantle) site, Ontario, yield an ambiguous result: more or less similar probability around AD 1500 or alternatively around AD 1600. This village site, likely of no more than ca. 20–30 years total duration, illustrates the challenges of high-resolution dating across periods with a reversal/plateau in the 14 C calibration curve. Another problem we identify is the tendency for dating probability for short-duration sites to sometimes be overly compressed as dating intensity increases under analysis with OxCal, and for probability to shift away from the real age range especially during reversal/plateau episodes. To address both issues additional constraints are necessary. While a tree-ring sequenced 14 C “wiggle-match” is the best option where available, we investigate how, in the absence of such an option, use of the in-built age in wood-charcoal samples can be used to distinguish the likely correct date range. This approach can resolve ambiguities in dating, e.g., for shorter-duration Late Woodland village sites in northeastern North America, but also other short-duration cases corresponding with reversal/plateau episodes on the 14 C calibration curve. We place the Jean-Baptiste Lainé site most likely in a range between ca. AD 1595–1626 (95.4% probability). 

The timeframe of Indigenous settlements in Northeast North America in the 15 th -17 th centuries CE has until very recently been largely described in terms of European material culture and history. An independent chronology was usually absent. Radiocarbon dating has recently begun to change this conventional model radically. The challenge, if an alternative, independent timeframe and history is to be created, is to articulate a high-resolution chronology appropriate and comparable with the lived histories of the Indigenous village settlements of the period. Improving substantially on previous initial work, we report here high-resolution defined chronologies for the three most extensively excavated and iconic ancestral Kanienʼkehá꞉ka (Mohawk) village sites in New York (Smith-Pagerie, Klock and Garoga), and a fourth early historic Indigenous site, Brigg’s Run, and re-assess the wider chronology of the Mohawk River Valley in the mid-15 th to earlier 17 th centuries. This new chronology confirms initial suggestions from radiocarbon that a wholesale reappraisal of past assumptions is necessary, since our dates conflict completely with past dates and the previously presumed temporal order of these three iconic sites. In turn, a wider reassessment of northeastern North American early history and re-interpretation of Atlantic connectivities in the later 15 th through early 17 th centuries is required. Our new closely defined date ranges are achieved employing detailed archival analysis of excavation records to establish the contextual history for radiocarbon-dated samples from each site, tree-ring defined short time series from wood charcoal samples fitted against the radiocarbon calibration curve (‘wiggle-matching’), and Bayesian chronological modelling for each of the individual sites integrating all available prior knowledge and radiocarbon dating probabilities. We define (our preferred model) most likely (68.3% highest posterior density) village occupation ranges for Smith-Pagerie of ~1478–1498, Klock of ~1499–1521, Garoga of ~1550–1582, and Brigg’s Run of ~1619–1632. 

ABSTRACT Reversals and plateaus in the radiocarbon ( 14 C) calibration curve lead to similar 14 C ages applying to a wide range of calendar dates, creating imprecision, ambiguity, and challenges for archaeological dating. Even with Bayesian chronological modeling, such periods remain a problem when no known order—e.g., a stratigraphic sequence—exists, and especially if site durations are relatively short. Using the reversal/plateau AD 1480–1630 and the archaeology of northeastern North America as our example, we consider possible strategies to improve chronological resolution across such reversal/plateau periods in the absence of stratigraphic sequences, including uses of wood-charcoal TPQs from even very short wiggle-matches, and site phase duration constraints based on ethnohistoric and archaeological evidence. 

The new IntCal20 radiocarbon record continues decades of successful practice by employing one calibration curve as an approximation for different regions across the hemisphere. Here we investigate three radiocarbon time-series of archaeological and historical importance from the Mediterranean-Anatolian region, which indicate, or may include, offsets from IntCal20 (~0–22¹⁴C years). While modest, these differences are critical for our precise understanding of historical and environmental events across the Mediterranean Basin and Near East. Offsets towards older radiocarbon ages in Mediterranean-Anatolian wood can be explained by a divergence between high-resolution radiocarbon dates from the recent generation of accelerator mass spectrometry (AMS) versus dates from previous technologies, such as low-level gas proportional counting (LLGPC) and liquid scintillation spectrometry (LSS). However, another reason is likely differing growing season lengths and timings, which would affect the seasonal cycle of atmospheric radiocarbon concentrations recorded in different geographic zones. Understanding and correcting these offsets is key to the well-defined calendar placement of a Middle Bronze Age tree-ring chronology. This in turn resolves long-standing debate over Mesopotamian chronology in the earlier second millennium BCE. Last but not least, accurate dating is needed for any further assessment of the societal and environmental impact of the Thera/Santorini volcanic eruption.

 

Reversals and plateaus in the radiocarbon (14C) calibration curve lead to similar 14C ages applying to a wide range of calendar dates, creating imprecision, ambiguity, and challenges for archaeological dating. Even with Bayesian chronological modeling, such periods remain a problem when no known order—e.g., a stratigraphic sequence—exists, and especially if site durations are relatively short. Using the reversal/plateau AD 1480–1630 and the archaeology of northeastern North America as our example, we consider possible strategies to improve chronological resolution across such reversal/plateau periods in the absence of stratigraphic sequences, including uses of wood-charcoal TPQs from even very short wiggle-matches, and site phase duration constraints based on ethnohistoric and archaeological evidence. 

La datation par le radiocarbone est rarement utilisée dans l'archéologie de l'Amérique du Nord, historique ou de l’époque des contacts, en raison des particularités de la courbe de calibration qui donnent lieu aux dates ambiguës pour le calendrier. Nous explorons le potentiel et les exigences pour les datations radiocarbone et d'analyses Bayésienne afin de créer un calendrier pour les sites de début de la période contact dans le nord-est de l'Amérique du Nord séparent des hypothèses et approximations impliquées dans les constructions temporelles basées sur les marchandises commerciales et d'autres corrélats archéologiques. Comme démonstration, nous utilisons la modélisation chronologique Bayésienne pour analyser les dates par le radiocarbone sur des échantillons éphémères et un poteau de quatre sites Huron-Wendat Arendarhonon (Benson, Sopher, Ball et Warminster) afin d’établir une chronologie indépendante. Nous trouvons que Warminster était probablement occupé pendant 1615–1616, ce qui en fait le candidat le plus probable pour le site de Cahiagué visité par Samuel de Champlain en 1615–1616, par rapport à l'autre alternative principale suggérée, Ball, qui est plus ancien, comme les sites Sopher et Benson. En fait, le site Benson semble dater d'environ cinquante ans (~50) plus tôt que prévu. Nous présentons les méthodes employées pour arriver à ces nouvelles estimations d’âge indépendant et affirmons qu'une re-datation absolue des sites de l'époque historique est nécessaire pour évaluer avec précision les interprétations existantes basées sur la datation relative et les récits régionaux associés. 

A time frame for late Iroquoian prehistory is firmly established on the basis of the presence/absence of European trade goods and other archeological indicators. However, independent dating evidence is lacking. We use 86 radiocarbon measurements to test and (re)define existing chronological understanding. Warminster, often associated with Cahiagué visited by S. de Champlain in 1615–1616 CE, yields a compatible radiocarbon-based age. However, a well-known late prehistoric site sequence in southern Ontario, Draper-Spang-Mantle, usually dated ~1450–1550, yields much later radiocarbon-based dates of ~1530–1615. The revised time frame dramatically rewrites 16th-century contact-era history in this region. Key processes of violent conflict, community coalescence, and the introduction of European goods all happened much later and more rapidly than previously assumed. Our results suggest the need to reconsider current understandings of contact-era dynamics across northeastern North America. 

Los métodos dendrocronológicos tienen el potencial de proporcionar fechas de calendario precisas, sin embargo son escasamente utilizados en las investigaciones arqueológicas Mesoamericanas. Esto se debe a la existencia de varios supuestos de larga permanencia, pero erróneos tales como: que los anillos de los árboles en esta región no reflejan el crecimiento anual y la variabilidad medioambiental, que no existe un número adecuado de muestras, y que las mediciones de los anillos de los árboles no pueden ser útiles sin la existencia de árboles modernos para vincular las curvas prehispánico. En este artículo, se presentan datos de los sitios de La Quemada y Los Pilarillos, localizados en el Valle de Malpaso, Zacatecas, para demostrar que existen muestras arqueológicas dendrocronológicamente adecuadas, medibles, que se pueden “ cross-date ”, y que se pueden obtener fechas precisas usando un método llamado “calibración de radiocarbono de secuencias definidas” ( radiocarbon wiggle-matching ). El trabajo pone en evidencia el potencial de estos métodos para abordar cuestiones cronológicas, y en el futuro, también climáticas, las cuales hasta la fecha han eludido el trabajo arqueológico en la región.