After an intercomparison age experiment carried out in the framework of the first MODIS (MOrtar Dating Inter-comparison Study) project, the results showed general agreement both between optically stimulated luminescence (OSL) dating laboratories and with radiocarbon (14C) dating results. As the needs for the selection of samples convenient for an inter-comparison are not the same between 14C and OSL, for the second running, it has been decided to choose two different sample sets, one to share between the radiocarbon labs and one for the OSL dating ones. The results obtained by applying different experimental protocols (multigrain and single grain techniques) and different statistical models (weighted mean, central age mode, average dose model, minimum age model and exponential exposure dose) are discussed in this work.

The eastern Great Lakes Late Quaternary timescale is based on older thermoluminescence dates and on uncalibrated radiocarbon dates from extensive sections along the north shores of Lakes Erie and Ontario. New optically stimulated luminescence dates from Late Quaternary delta sediments from the north shores of Lake Erie at Sand Hills Park give consistent ages of 23.5 to 20.5 ka. This is 4 to 7 ka older than previously assigned based on lithologic correlation with 16.5 ka calibrated radiocarbon dated sediments 5 km to the west at Vanderven. On the existing eastern Great Lakes stratigraphy, it puts deposition of these Sand Hills Park sediments in the Erie interstadial and not in the fluctuating postglacial glacial retreat of the Mackinaw phase to which the Vanderven sediments belong. The Sand Hills delta and underlying diamicts must have been overridden by the Porty Bruce advance at 18 ka. IntCal20 calibration of existing radiocarbon ages suggests that the physical stratigraphic relations of the various Wisconsin units are accurate and that the existing timescale is simply too young.

Intense aeolian processes in arid and semi-arid environments play an essential role in the preservation and destruction of archeological sites. This is especially the case in the lower basin of the Colorado River at the eastern Pampa-Patagonia Transition of Argentina, as is illustrated by geoarchaeological and chronostratigraphic studies at a mid-Holocene hunter-gatherer site, La Modesta, where aeolian processes strongly influence the archeological record in dune sediments. At La Modesta, surface archaeological materials are numerous and well preserved, although the stratigraphic record is incomplete. Optically stimulated luminescence (OSL) dating of sediments that contain cultural material provides a chronology dating from ca. 8.2 ka but shows one or more hiatuses from ca. 6–2 ka in the sedimentary succession. Intense morphogenesis related to arid climates likely caused gaps in sedimentation, affecting the integrity and resolution of the archaeological record. This study helps explain mid-Holocene archaeological discontinuities throughout central Argentina and highlights the importance of considering taphonomic and geologic biases when dealing with the absence or reduction of the archaeological record in dryland regions.

Brzezie in the Pleszew region was first mentioned in archaeological literature, as the location where a treasure of gold artifacts dating back to the 3rd period of the Bronze Age was discovered in 1876. Archaeological research has been conducted there almost continuously since 1985. The result of many years of fieldwork is the discovery of 363 late Bronze Age and Early Iron Age graves, as well as 50 burials of the Przeworsk culture from the era of Roman influence. In the last few years, further research has been conducted by archeologist Grzegorz Szczurek. After comprehensive geophysical prospecting, the extent of the necropolis was established, and more graves were excavated. For the first time, materials for radiocarbon and luminescence dating were also collected to determine the absolute chronology for this archaeological site. Four samples were dated in the Poznań radiocarbon laboratory, and five luminescence tests were conducted in the Gliwice luminescence laboratory. Due to the complete thermo-destruction of collagen in human bones, age determination was based on carbonate fractionation. In one case, a piece of charcoal was selected for dating purposes. Considering uncertainties and the fact that both methods date different events, the results reveal concurrence, giving a 1000–500 BC range.

The most widely used dating techniques in quaternary research are the radiocarbon (14C) and optically stimulated luminescence (OSL) dating methods. In some environments, the investigated sediments do not contain enough material for 14C dating. In these cases, 14C dating of bulk sediment may be used as a last resort. The major aim of the present study was to determine the reliability and limitations of the different fractions of the soil organic carbon (SOC) 14C ages in the Nyírség blown-sand study area, in Hungary. Therefore, the low- and high-temperature combustions of SOC (LT-SOC and HT-SOC) 14C age of fossil soils were compared with the charcoal ages from the same fossil soil layer, and their (LT-SOC, HT-SOC, and charcoal) age reliability was verified independently by applying OSL to the quartz fraction of the sediment samples. The 14C data show variable agreement with OSL ages. Charcoal fragments were collected from some of the best material for 14C dating and their ages are in agreement with the LT and HT-SOC 14C ages and OSL data. The 14C age LT-SOC gives a reliable, credible ages, which were confirmed by independent OSL measurements. If buried soils do not contain any other macroscopic remnants for 14C dating, the LT-SOC 14C ages can be used, in the case of the Nyírség study area. The LT-SOC, which is the younger fraction of the soil organic carbon, may be considered to represent the burial time of the fossil soil layer. The HT-SOC 14C ages are sometimes unrealistically older than expected and cannot be considered to be reliable.

The Deliblato Sands is among the largest uniform dune fields of Europe, with a very pronounced topography reflecting extensive past aeolian events. Although lacking numerical age data, previous researchers have hypothesized various periods of dune formation. Our research goals were to map the main morphological units of the Deliblato Sands, and to provide the first optically stimulated luminescence (OSL) ages for the major dune types. Mapping was carried out using digital elevation models, satellite images, and GPS profiles. Dune development was investigated using OSL. Several tests were performed concerning thermal treatment, signal characteristics, dose recovery, and dose distributions to assess the suitability of sediments for luminescence dating. Based on our results, two dune generations could be identified that differed in morphology and age. Older dune forms are primarily low sand-supply, hairpin-like parabolic dunes that developed from the last glacial maximum until the end of the early Holocene, then became stabilized. Younger, superimposed parabolic dunes record an intensive aeolian signal from the eighteenth and nineteenth centuries. The history of the Deliblato Sands fits with those from other European sand dune areas, and provides further details to understand paleoenvironmental changes in the region.

Environmental information from place-names has largely been overlooked by geoarchaeologists and fluvial geomorphologists in analyses of the depositional histories of rivers and floodplains. Here, new flood chronologies for the rivers Teme, Severn, and Wye are presented, modelled from stable river sections excavated at Broadwas, Buildwas, and Rotherwas. These are connected by the Old English term *wæsse, interpreted as ‘land by a meandering river which floods and drains quickly’. The results reveal that, in all three places, flooding during the early medieval period occurred more frequently between AD 350–700 than between AD 700–1100, but that over time each river's flooding regime became more complex including high magnitude single events. In the sampled locations, the fluvial dynamics of localized flood events had much in common, and almost certainly differed in nature from other sections of their rivers, refining our understanding of the precise nature of flooding which their names sought to communicate. This study shows how the toponymic record can be helpful in the long-term reconstruction of historic river activity and for our understanding of past human perceptions of riverine environments.

After the last damaging earthquake in 2012, an anti-seismic reinforcement project of the cathedral of Modena was designed giving us the opportunity to investigate and date the building materials. Radiocarbon (14C), optically stimulated luminescence (OSL), and thermoluminescence (TL) dating techniques were performed on the vaults with the aim to (1) clarify the construction timing, (2) define the history of the restorations, and (3) explore the possible correlation of the main restoration works to the earthquake chronology deduced from the historic catalog. Preliminary results show that medieval older bricks were reused for most of the original construction. Only lime and non-gypsum mortar was used for the original construction in the 15th century and for later repair of damage caused by earthquakes in the 16th and 17th centuries. Gypsum mortar was used for later repair in the 18th century. The results show much stronger damage due to earthquakes than previously thought.

In this study, we investigate quartz-based luminescence optical dating of Iron Age deposits at the archaeological site of Tell Damiyah in the Jordan valley. Ten samples, taken from different occupation layers from two different excavation areas, proved to have good luminescence characteristics (fast-component dominated, dose recovery ratio 1.032 ± 0.010, n=24). The optical ages are completely consistent with both available 14C ages and ages based on stylistic elements; it appears that this material was fully reset at deposition, although it is recognised that the agreement with age control is somewhat dependent on the assumed field water content of the samples. Further comparison with different OSL signals from feldspar, or investigations based on dose distributions from individual grains would be desirable to independently confirm the resetting of this material. It is concluded that the sediments of Tell Damiyah are very suitable for luminescence dating. Despite the relatively large associated age uncertainties of between 5 and 10%, OSL at tell sites has the potential to provide ages for material very difficult to date by conventional methods, and to identify reworked mixtures of older artifacts in a younger depositional setting.

Well-stratified Middle Palaeolithic assemblages are extremely rare in Mongolia. Initially investigated between the 1960s and 1990s, three major Middle Palaeolithic sites in the Orkhon Valley of central Mongolia yielded a large quantity of data and generated many research questions that still await answers. Re-investigation of these sites has uncovered chronostratigraphic and cultural sequences that may shed new light on human dispersal routes.

Stratigraphic evidence and extensive optically stimulated luminescence (OSL) geochronology from an 18-km-long reach of the middle Rangitata Valley, South Island, New Zealand, provide evidence for at least six distinct glacial advances during the last glacial cycle. These include four well-constrained Marine Oxygen Isotope Stage (MIS) 3 and 2 advances at ca. 38 ka, ca. 27 ka, ca. 21 ka and at 18 ka, as well as less well-constrained advances in MIS 4 and/or early MIS 3. Ice occupied a farther downvalley reach of the Rangitata from 38 ka to after 18 ka, indicating that near-full glacial conditions persisted for most of the last 20 ka of the last glaciation, though the glacier still fluctuated significantly, as reflected by the numerous distinguishable advances. Global or regional cooling alone cannot explain the persistence of near-maximum glacial conditions for this extended period, nor can it explain the occurrence of the largest advances ca. 32 ka. Instead, we invoke the northward expansion of the westerlies during MIS 3 as the cause for the early widespread glaciation, wherein enhanced westerly flow under moderate cooling maximised glacial extents. Local insolation favoured extended MIS 3 glaciation until ca. 32 ka. Increasing summer insolation gradually reduced glacial extents after ca. 28 ka.

Absolute dating of mortars is crucial when trying to pin down construction phases of archaeological sites and historic stone buildings to a certain point in time or to confirm, but possibly also challenge, existing chronologies. To evaluate various sample preparation methods for radiocarbon (14C) dating of mortars as well as to compare different dating methods, i.e. 14C and optically stimulated luminescence (OSL), a mortar dating intercomparison study (MODIS) was set up, exploring existing limits and needs for further research. Four mortar samples were selected and distributed among the participating laboratories: one of which was expected not to present any problem related to the sample preparation methodologies for anthropogenic lime extraction, whereas all others addressed specific known sample preparation issues. Data obtained from the various mortar dating approaches are evaluated relative to the historical framework of the mortar samples and any deviation observed is contextualized to the composition and specific mineralogy of the sampled material.

Seven radiocarbon laboratories: Åbo/Aarhus, CIRCE, CIRCe, ETHZ, Poznań, RICH, and Milano-Bicocca performed separation of carbonaceous fractions suitable for 14C dating of four mortar samples selected for the MOrtar Dating Inter-comparison Study (MODIS). In addition, optically stimulated luminescence (OSL) analyses were completed by Milano-Bicocca and IRAMAT-CRP2A Bordeaux. Each laboratory performed separation according to laboratory protocol. Results of this first intercomparison show that even though consistent 14C ages were obtained by different laboratories, two mortars yielded ages different than expected from the archaeological context.

The earliest peopling of South America remains a contentious issue. Despite the growing amount of new evidence becoming available, and improved excavation and dating techniques, few sites have yet to be securely assigned to a period earlier than 12000 BP. The Santa Elina shelter in Brazil, located at the convergence of two major river basins, is one of them. The excavations at the site, including the results of various dating programmes, are described here along with reflections on the unique insights offered by Santa Elina into early migration routes into the Southern Cone.

This is a reply to a rejoinder to our work in the Negev Highlands (Shahack-Gross and Finkelstein 2015) recently published by Bruins and van der Plicht in this journal (2017a). It addresses archaeological method and practice related to the way evidence for the timing of dry farming in the arid Negev Highlands, Israel, has been obtained. We highlight issues related to phytolith assemblages and livestock dung found in Negev Highlands sites as an indicator for presence/absence of cereal crops, and briefly discuss methods with which terraced agricultural plots in the region have been dated. We touch upon issues at the core of the scientific method, especially the need for proper controls and the importance of reporting full sets of data. Based on the new data presented by Bruins and van der Plicht (2017a, 2017b) we propose an alternative interpretation for their dating of a single terrace at Horvat Haluqim.

Accurate sea-level reconstruction is critical in understanding the drivers of coastal evolution. Inliers of shallow marine limestone and aeolianite are exposed as zeugen (carbonate-capped erosional remnants) on the southern coast of the Arabian/Persian Gulf. These have generally been accepted as evidence of a eustatically driven, last-interglacial relative sea-level highstand preceded by a penultimate glacial-age lowstand. Instead, recent optically stimulated luminescence (OSL) dating suggests a last glacial age for these deposits, requiring >100 m of uplift since the last glacial maximum in order to keep pace with eustatic sea-level rise and implying the need for a wholesale revision of tectonic, stratigraphic and sea-level histories of the Gulf. These two hypotheses have radically different implications for regional neotectonics and land–sea distribution histories. Here we test these hypotheses using OSL dating of the zeugen formations. These new ages are remarkably consistent with earlier interpretations of the formations being last interglacial or older in age, showing that tectonic movements are negligible and eustatic sea-level variations are responsible for local sea-level changes in the Gulf. The cause of the large age differences between recent studies is unclear, although it appears related to large differences in the measured accumulated dose in different OSL samples.

Optically stimulated luminescence dated sand dunes and Pleistocene beach ridges in northwest Ohio are used to reconstruct landscape modification more than 5000 yr after deglaciation. Four of the OSL ages (13.3–11.1 ka) cluster around the Younger Dryas cold event, five ages (10.8–8.2 ka) cluster around the Preboreal, one young age (0.9–0.7 ka) records more recent aeolian activity, and one age of 15.1–13.1 ka dates a barrier spit in Lake Warren. In northwest Ohio, both landscape instability recorded by aeolian activity and a vegetation response recorded by pollen are coeval with the Younger Dryas. However, the climate conditions during the Preboreal resulting in aeolian activity are not recorded in the available pollen records. From this, we conclude that aeolian dunes and surfaces susceptible to deflation are sensitive to cooler, drier episodes of climate and can complement pollen data. Younger Dryas and Preboreal aged aeolian activity in northwestern Ohio coincides with aeolian records elsewhere in the Great Lakes region east of the prairie–forest ecotone.

Late Quaternary reflooding of the Persian Gulf climaxed with the mid-Holocene highstand previously variously dated between 6 and 3.4 ka. Examination of the stratigraphic and paleoenvironmental context of a mid-Holocene whale beaching allows us to accurately constrain the timing of the transgressive, highstand and regressive phases of the mid- to late Holocene sea-level highstand in the Persian Gulf. Mid-Holocene transgression of the Gulf surpassed today's sea level by 7100–6890 cal yr BP, attaining a highstand of > 1 m above current sea level shortly after 5290–4570 cal yr BP before falling back to current levels by 1440–1170 cal yr BP. The cetacean beached into an intertidal hardground pond during the transgressive phase (5300–4960 cal yr BP) with continued transgression interring the skeleton in shallow-subtidal sediments. Subsequent relative sea-level fall produced a forced regression with consequent progradation of the coastal system. These new ages refine previously reported timings for the mid- to late Holocene sea-level highstand published for other regions. By so doing, they allow us to constrain the timing of this correlatable global eustatic event more accurately.

Geomorphic, stratigraphic and geochronological evidence from northeast British Columbia (Canada) indicates that, during the late Wisconsinan (approximately equivalent to marine oxygen isotope stage [MIS] 2), a major lobe of western-sourced ice coalesced with the northeastern-sourced Laurentide Ice Sheet (LIS). High-resolution digital elevation models reveal a continuous 75 km-long field of streamlined landforms that indicate the ice flow direction of a major northeast-flowing lobe of the Cordilleran Ice Sheet (CIS) or a montane glacier (>200 km wide) was deflected to a north-northwest trajectory as it coalesced with the retreating LIS. The streamlined landforms are composed of till containing clasts of eastern provenance that imply that the LIS reached its maximum extent before the western-sourced ice flow crossed the area. Since the LIS only reached this region in the late Wisconsinan, the CIS/montane ice responsible for the streamlined landforms must have occupied the area after the LIS withdrew. Stratigraphy from the Murray and Pine river valleys supports a late Wisconsinan age for the surface landforms and records two glacial events separated by a non-glacial interval that was dated to be of middle Wisconsinan (MIS 3) age.

A high-resolution chronology for Peoria (last glacial period) Loess from three sites in Nebraska, midcontinental North America, is determined by applying optically stimulated luminescence (OSL) dating to 35–50 μm quartz. At Bignell Hill, Nebraska, an OSL age of 25,000 yr near the contact of Peoria Loess with the underlying Gilman Canyon Formation shows that dust accumulation occurred early during the last glacial maximum (LGM), whereas at Devil’s Den and Eustis, Nebraska, basal OSL ages are significantly younger (18,000 and 21,000 yr, respectively). At all three localities, dust accumulation ended at some time after 14,000 yr ago. Mass accumulation rates (MARs) for western Nebraska, calculated using the OSL ages, are extremely high from 18,000 to 14,000 yr—much higher than those calculated for any other pre-Holocene location worldwide. These unprecedented MARs coincide with the timing of a mismatch between paleoenvironmental evidence from central North America, and the paleoclimate simulations from atmospheric global circulation models (AGCMs). We infer that the high atmospheric dust loading implied by these MARs may have played an important role, through radiative forcing, in maintaining a colder-than-present climate over central North America for several thousand years after summer insolation exceeded present-day values.