Radiocarbon and dendrochronological dating of Sub-fossil oaks from Smarhoń riverine sediments

Sub-fossil oaks from Smarhoń in Belarus have been investigated and tree-ring chronologies were assembled. According to radiocarbon dating, the oldest oak grew from 5782–5612 cal BC and the youngest from 1575–1747 cal AD. Radiocarbon and dendrochronological dating of 97 samples, four single series, 10 mean curves (containing 2–9 series) and three chronologies (10–25 series) were constructed. The longest chronology (No. 16), covering 549 years, was absolutely dated against various oak chronologies of Polish/Baltic origin to AD 778–1326. Germination and dying-off phases were assessed from the three best replicated chronologies. A spectral analysis of the chronologies provided cycles of variable length, on average of 25 years.     

Locating the origins of wood resources: a review of dendroprovenancing

Dendroprovenancing studies have been shown to have historically been initiated on the use of oak in art-historical contexts, but are now employed on a much wider range of species and artefact types, particularly in relation to ship remains. The commonest methodology is to compare individual site chronologies with a network of other chronologies, and to recognise trends in the geographical distribution of strong matches, suggesting the likely source area of the material. Other studies may look at the matching of individual timbers to draw similar conclusions. It is shown that ecological and genetic factors may strongly influence individual matching results and that ring-widths may therefore be considered a somewhat crude means of provenancing. Additional chemical and genetic markers are discussed, although these are unlikely to become routinely used in the near future.     

Tree-ring chronologies for the 6th to 16th centuries for oaks of southern and eastern England

The background to the problem of providing useful oak chronologies for the variable environmental conditions that apply in southern and eastern England is outlined. The reference chronologies published here embrace three new principles. Firstly, the samples, nearly 300, on which they are based are almost entirely of boards or planks that are of radial section (from oaks aged on average about 250 years) that form part of panel paintings or chests. Secondly, to take account of the differences in the growth pattern with the vigour of growth, separate chronologies for sequences of different ring-width have been formed. Thirdly, on account of the difficulties in extending, with the samples available, an English chronology by the method of overlapping, eight separate chronologies, each about 300 years long, have been created. Matching has been based on German methods, i.e. computer comparisons (with more than one reference chronology) supported by visual comparison of charts. Agreement values in about half a million positions were calculated.These reference chronologies, expressed as ring-widths, are suitable for application to oaks that have grown within a region of considerable size that covers both sides of the North Sea. For panels used as a support for paintings of the 15th and 16th centuries, they have dated 85% of 130 English (London area) ones and about the same percentage of 25 Flemish ones. Rather earlier, sequences for oak boards used in places as far apart as York, Norwich, Oxford and Winchester have been matched. In the 10th to 12th centuries, the ring-width chronology derived for the London area shows good agreement with those for the hilly regions of Germany and that for Schleswig, as well as dating floor planks from Viking houses in York. A floating chronology, 322 years long, dataed to the 6th to 9th centuries by several radiocarbon analyses, has been formed from long sequences of rings from timbers excavated at Old Windsor and Portchester: this has matched material from Southampton and is linked with a mean curve for the well at North Elmham (Norfolk) and the strakes of the Graveney ship.     

Oaks,tree-rings and wooden cultural heritage: a review of the main characteristics and applications of oak dendrochronology in Europe

We overview the recent development of oak dendrochronology in Europe related to archaeology and art-history. Tree-ring series of European oaks (Quercus robur and Q. petraea) have provided a reliable framework for chronometric dating and reconstruction of past climate and environment. To date, long oak chronologies cover almost the entire Holocene, up to 8480 BC and the network over the entire area in which the two oaks grow is being improved. We present the main characteristics of oak ring series and discuss the latest methodological advances in defining the calendar year in which the tree-rings were formed and in interpreting such dating in terms of the age of a wooden object. Dendrochronology has established itself as a standard dating tool and has been applied in a wide variety of (pre-)historical studies. Archaeological wood, historical buildings, works of art (such as panel paintings and sculptures) have been successfully investigated. Recent advances in dendro-provenancing have helped to obtain more information on the timber trade in the past. Information on past forest structures, silviculture and timber use have become available through scrutinizing historical and contemporary ring-width patterns.     

Dendrochronological dating of wooden artifacts by measuring the tree rings using magnifying glass and photography-assisted method: an example of a Dutch panel painting

Dendrochronology, an analysis of tree rings, is a commonly used method for dating wooden structures in archaeological remains and historical objects. Fascinating subjects of examination are the historical oil paintings on oak panels. Here, we applied a tree ring analysis on three boards of a Dutch painting from the Sinebrychoff Art Museum (Helsinki). Tree rings were measured using the conventional lens-assisted method, in addition to the photography-based approach, where the widths of the rings were determined from digital enlargements of the photos. These two methods produced comparable tree ring series. The lens- and photography-based records of the measured panel exhibited higher agreement with each other than the conventional, lens-based, record against the different master chronologies. Dendrochronological cross-dating against the master chronology showed that the rings of the panel represent the period ad 1413–1620. Cross-dating was attained by comparing the tree ring series of the panel painting with the previously published chronologies obtained from timber transported from the historical ports of the Eastern Baltic Sea to Western Europe. Photography appears as a promising method to be used for dendrochronological investigations of archaeological and historical objects, alongside the conventional methods. We note that the importance of using photographs of tree ring cross sections was highlighted already in the 1930s. In the digital era, the photographic approach shows obvious benefits for archival purposes and remeasuring the rings, with additional future prospects of image processing and analyses.     

Iberian Dendrochronology and the Newport Medieval Ship

At the time of the discovery of the Newport medieval ship, it proved impossible to date the timbers used in its original construction through dendrochronology. Associated British timbers and artefacts provided dating to the mid 15th century, with the latter pointing to strong Iberian connections. The development of regional oak ring‐width chronologies in the Basque Country, and their extension back in time to overlap with the ring‐width mean developed for the Newport Ship, has allowed absolute dating and provenance of timbers used in its original construction. Further research is required to clarify the geographical source of the timbers and to develop a high‐resolution network of tree‐ring data for the region.     

Reproducing the indigenous: John Møller’s studio portraits of Greenlanders in context

Between 1889 and 1922, John Møller (1867–1935), the first professional Greenlandic photographer, produced more than 3000 glass plate negatives documenting life in Western Greenland around the turn of the twentieth century. Rooted in an internal understanding of self, Møller’s photographs played an important part in the formation of a contemporary image of Greenlandic indigenous identity. At the same time, Møller’s photographic practice was arguably entangled in and delimited by a historical reality that was structured by colonial relations of power. This paper examines the social and art-historical contexts of Møller’s work, focusing in particular on a selection of his formal studio portraits. My reading of these portraits suggests a case in which conflicting impulses coincide. On the one hand, Møller produced images that played out the “ethnographic convention”, a European form of representation dating back to the sixteenth century used for the documentation of non-Western indigenous peoples as specimens. However, in acting out that convention, Møller’s photographs hint at a subtle, progressive building-up of identity that reclaimed images of Greenlanders for themselves, and turned an originally negative, external image of indigeneity into a positive sense of self.     

Dendrochronological and radiocarbon dating of subfossil wood from the Morava River basin

The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River. The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001. 160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and 7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10^th–15^th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing standard chronology or to create a long floating average treering curve.     

Radiocarbon Wiggle-Match Dating in the Intertidal Zone

Radiocarbon wiggle-match dating is a technique that can combine the versatility of radiocarbon dating with chronological information from tree-rings. This makes it useful in contexts where timbers are preserved, but dendrochronological dating is impossible. As intertidal and marine timbers are waterlogged, this can favor their preservation and hence allow wiggle-match ¹⁴C dating, which can be of significant help in deriving relatively precise chronologies for a range of coastal structures. As the technique depends on making multiple radiocarbon measurements towards a single date, efficiency in application is the key and hence a number of practical considerations need to be taken into account in advance of conducting a dating program. This paper discusses some of these practical concerns and reviews them in the context of the intertidal crannogs in the Firth of Clyde on the west coast of Scotland.     

Dating Historical Buildings: An Update on the Possibilities of Absolute Dating Methods

The reconstruction of the history of a building represents a difficult task, as written information is not usually available or incomplete. Some building materials (e.g., bricks, wood) have been classically used for absolute dating while on others has been considered unreliable (e.g., stone). However, developments and tests performed in the last 20 years have shown important advances on the use of such methods, increasing the possibilities of successful reconstruction of building chronologies, although most of these advances are still scarcely known by the community involved in the site management (e.g., archaeologists, architects). Both, radiocarbon and luminescence dating have been the most successful techniques but others, such as archaeomagnetism, can also be used. Even, some important events such as fires could be dated. The purpose of this work is to provide an overview of the last achievements of absolute dating techniques available in building materials.     

DATING OF THE HOMINID (HOMO NEANDERTHALENSIS) REMAINS ACCUMULATION FROM EL SIDRÓN CAVE (PILOÑA,ASTURIAS, NORTH SPAIN): AN EXAMPLE OF A MULTI‐METHODOLOGICAL APPROACH TO THE DATING OF UPPER PLEISTOCENE SITES

The age of Neanderthal remains and associated sediments from El Sidrón cave has been obtained through different dating methods (¹⁴CAMS, U/TH, OSL, ESR and AAR) and samples (charcoal debris, bone, tooth dentine, stalagmitic flowstone, carbonate‐rich sediments, sedimentary quartz grains, tooth enamel and land snail shells). Detrital Th contamination rendered Th/U dating analyses of flowstone unreliable. Recent ¹⁴C contamination produced spurious age‐values from charcoal samples as well as from inadequately pretreated tooth samples. Most consistent ¹⁴C dates are grouped into two series: one between 35 and 40 ka and the other between 48 and 49 ka. Most ESR and AAR samples yielded concordant ages, ranging between 39 and 45 ka; OSL dating results permitted adequate bracketing of the sedimentary layer that contained the human remains. Our results emphasize the value of multi‐dating approaches for the establishment of reliable chronologies of human remains.     

Selective woodland exploitation for charcoal production. A detailed analysis of charcoal kiln remains (ca. 1300–1900 AD) from Zoersel (northern Belgium)

A detailed study of charcoal burning activities has been made for the Zoersel forest (Northern Belgium) based on an inventory of charcoal kiln remains, the analyses of wood charcoal and other charred botanical macroremains and radiocarbon dating of 10 of these kilns. Age determination of the youngest kilns was refined by dendrochronological analysis of trees growing on top of these kiln sites. The results show that, although many kilns were found, charcoal was produced in Zoersel only at certain moments during late and post-medieval times suggesting that charcoal burning was not a part of the regular management practice of these forests. The wood used for the production of charcoal mainly consists of taxa of alluvial (alder) forests while the kilns are situated on sites that currently are rather dry, with an oak dominated vegetation. For the older kilns, this contrast could be explained by an important change in local soil conditions. The younger kilns may be related to the conversion of alder woodland to grassland in the lower parts of the domain, with the kilns being constructed in the nearby dryer woodland areas.     

Fluvial sediments, correlations and palaeoenvironmental reconstruction: The development of robust radiocarbon chronologies

Multiple sequences of radiocarbon dates extracted from organic materials are increasingly being used to provide robust chronologies for landscape development, particularly the timing and correlation of significant climatic and ‘process’ events. Whilst the validity of using such frameworks in sedimentary environments such as lake basins and raised bogs has been the focus of much attention, such debates have not extended to fluvial systems. Using examples from three lowland, vertically accreting river valleys in East Anglia, UK, this paper assesses the robustness of their associated radiocarbon chronologies by assessing the contrasting age estimates that are obtained by dating different parts of the same organic sample (humic, humin and plant macrofossils) at a variety of stratigraphic levels. Overall, the humin and humic acid fraction results were statistically consistent, whilst the plant macrofossil remains were found to be of a slightly younger age. In these examples, it is argued that the younger ages appear to be the result of Phragmites (common reed) roots pushing plant macrossils through the sedimentary sequence or opening up voids for material to fall through, although studies in lacustrine and mire environments suggest alternative explanations may also be possible. Whichever explanation is preferred, this study demonstrates clearly that the complexity of valley floor stratigraphy and processes is such, that using single radiocarbon dates, whether AMS or bulk samples to reconstruct chronologies of ‘geomorphic system response’ may need to be refined and subjected to the same level of assessment that has been applied in other sedimentary systems.     

DENDROCHRONOLOGY—A REFERENCE CURVE FOR SLOW GROWN OAKS,A.D. 1230 TO 1546

Details are given of how the widths of the annual rings of oak boards, which form the panels for certain sixteenth-century portraits painted in south-east England or adjacent parts of the Continent, have been matched with one another. A representative ring-width curve based on eighteen trees has been obtained and dated by region-to-region bridging from the master chronology, derived at Munich, for oaks grown in central and southern Germany. The feasibility of dendrochronology for oaks of slow and regular growth in late medieval times has been established for a region which extends beyond south-east England to Oxford on the west and to Flanders and parts of France on the east and south-east.     

Finding Mid-19th Century Native Settlements: Cartographic and Archaeological Evidence from Central California

Historical maps have the potential to aid archaeological investigations into the persistence of Native American settlements during the mid-19th century, a time when many Native communities disappear from archaeological view. Focusing on Tomales Bay in central California, we evaluate the usefulness of historical maps as a way to discover and interpret archaeological deposits dating to the period, with the aim of better understanding indigenous patterns of residence at the transition from missionary to settler colonialism. In particular, we focus on diseños and plats created to document Mexican-era land grants as well as early maps produced by the General Land Office and United States Coast Survey. Although we note inconsistencies regarding the inclusion of indigenous settlements on historical maps, our case study offers an example of how archaeologists can employ historical maps and targeted archaeological ground-truthing to discover sites that are poorly represented in the historical and archaeological records.     

Revealed by Waves: A Stratigraphic,Palaeoecological, and Dendrochronological Investigation of a Prehistoric Oak Timber and Intertidal Peats,Bay of Ireland,West Mainland,Orkney

An oak timber was discovered in 2013 within intertidal peats at the Bay of Ireland, Stenness, Orkney, representing a unique archaeological find. Subsequent excavation and rescue of the timber took place in 2014 to investigate its stratigraphical relationship before further eroding. Dendrochronological and morphological study identified the timber as a possible radially split log, c. 150 years of age when felled. No dendrochronological match was possible, and a wiggle-match date obtained provided a Later Mesolithic felling date of 4410–4325 cal BC. This timber is the first and only evidence so far for the use of oak in Mesolithic Orkney. The timber is significant palaeoecologically, suggesting oak may have been indigenous to Orkney. This adds to a growing argument for the existence of areas of “true woodland”. Pollen evidence shows the timber was deposited within reedswamp, fringed by willow-birch carr-woodland, with oak unlikely to have been growing in the immediate location. High microscopic and macroscopic charcoal values indicate Later Mesolithic communities exerted influence on this wetland using burning as a tool for landscape modification. It is unknown what the timber represents; it may have been for construction purposes or as a marker/possible landing place showing the path to the Loch of Stenness.     

Radiocarbon Dating and the Historical Archaeology of Korea: An Alternative Interpretation of Hongryeonbong Fortress II in the Three Kingdoms Period,Central Korea

Relying heavily upon historical records to build archaeological chronologies, many Korean historical archaeologists question the utility of radiocarbon dating. To challenge this tendency, we test a model based on historical records by analyzing radiocarbon dates. We dated two bulk samples from Hongryeonbong Fortress II, Seoul, South Korea, which is known historically to have been occupied between a.d. 500 and 551. By dividing bulk samples into smaller aliquots, we dated 40 subsamples and statistically estimated consensus dates. The consensus dates do not support expectations of the historical model, as they do not lie within the temporal range provided by historical records. We propose an alternative model that explains both the radiocarbon dates and the historical records. It is suggested that radiocarbon dating can be successfully applied to the reconstruction of historical periods and is a way of mitigating possible biases of models based solely on historical records.     

Expanding the utility of Uranium-series dating of speleothems for archaeological and palaeontological applications

Uranium-series (U-series) dating of speleothems is frequently used for palaeoclimate studies but its archaeological and palaeontological applications are limited to stratigraphically significant speleothem formations, such as flowstones, to provide maximum and minimum temporal points. This study targeted soda straw stalactites for U-series dating. In contrast to other speleothem formations, soda straw stalactites are fragile, have typically short life spans (usually only years but rarely up to a few hundred years) and are frequently incorporated into cave deposits. Results of thermal ionisation mass spectrometry (TIMS) U-series dating of soda straw stalactites from palaeontological excavations at Blanche Cave, South Australia, show that small, dense, clean straws tend to yield ages closest to the time of stratigraphic deposition. A correlation between soda straw U-series ages and radiocarbon ages of charcoal from the site is shown. Multiple soda straw age determinations for a single stratigraphic unit are required in order to verify age concordance. In conjunction with other dating methods, U-series dating of soda straw stalactites may help to significantly constrain the age of stratigraphic units and associated archaeological and palaeontological deposits in order to provide more robust chronologies. Here we advocate the collection of soda straw stalactites at future excavations of limestone cave sites.     

Historical Archaeology of Indigenous Culture Change in Mesoamerica

This essay outlines recent archaeological research on post-Columbian (c. A.D. 1500–1925) indigenous sites in Mexico and Central America. Historical archaeology is a growing field in Mesoamerica, and over the last 20 years investigations of native culture change have increased, especially in rural areas. Contemporary research contributes new insights on indigenous responses to Spanish colonization over a long period. This work also is reassessing chronologies and examining the diversity of indigenous behavior from late preconquest to historic times. Indigenous adaptations to culture contact and social change are characterized by three general stages: conquest, colonization, and independence. Although I do draw on other regions, the focus of the article is the Maya area and Central America, where more investigations have taken place.     

A STATISTICAL APPROACH TO THE CALIBRATION OF FLOATING TREE-RING CHRONOLOGIES USING RADIOCARBON DATES

The bristlecone pine tree-ring calibration of radiocarbon dates, while necessitating changes of up to 700 years in Holocene chronology before 1000 b.c. , offers possibilities of very accurate dating when ¹⁴C determinations from floating tree-ring chronologies are utilized. A statistical approach assuming linear regression is developed and used to position the floating tree-ring chronologies at Swiss neolithic sites, using radiocarbon dates published by Ferguson, Huber and Suess and by Suess. The statistical method gives objective estimated dates with estimates of error related, in a consistent and explicit manner, to the inherent inaccuracies of the radiocarbon dates. Most of the method may readily be tested by standard statistical procedures. For the particular cases considered the assumptions of linearity and parallelism are investigated, and the precision of the estimated dates is comparable with that claimed by Suess and his co-workers. A precise calibration is thus possible without utilizing the short-term fluctuations in the Suess calibration curve. The analysis, while avoiding some assumptions of Suess and his collaborators, offers an explicit procedure for establishing controlled teleconnections with the Ferguson dendrochronology, and supports their emphasis on the importance of radiocarbon dates from floating tree-ring sequences for the construction of precise prehistoric chronologies.