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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. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the impact of partial lateral scatter (LS), backscatter (BS) and presence of air gaps on optically stimulated luminescence dosimeter (OSLD) measurements in an acrylic miniphantom used for dosimetry audit on the 1.5 T magnetic resonance‐linear accelerator (MR‐linac) system. Methods: The following irradiation geometries were investigated using OSLDs, A26 MR/A12 MR ion chamber (IC), and Monaco Monte Carlo system: (a) IC/OSLD in an acrylic miniphantom (partial LS, partial BS), (b) IC/OSLD in a miniphantom placed on a solid water (SW) stack at a depth of 1.5 cm (partial LS, full BS), (c) IC/OSLD placed at a depth of 1.5 cm inside a 3 cm slab of SW/buildup (full LS, partial BS), and (d) IC/OSLD centered inside a 3 cm slab of SW/buildup at a depth of 1.5 cm placed on top of a SW stack (full LS, full BS). Average of two irradiated OSLDs with and without water was used at each setup. An air gap of 1 and 2 mm, mimicking presence of potential air gap around the OSLDs in the miniphantom geometry was also simulated. The calibration condition of the machine was 1 cGy/MU at SAD = 143.5 cm, d = 5 cm, G90, and 10 × 10 cm2. Results: The Monaco calculation (0.5% uncertainty and 1.0 mm voxel size) for the four setups at the measurement point were 108.2, 108.1, 109.4, and 110.0 cGy. The corresponding IC measurements were 109.0 ± 0.03, 109.5 ± 0.06, 110.2 ± 0.02, and 109.8 ± 0.03 cGy. Without water, OSLDs measurements were ∼10% higher than the expected. With added water to minimize air gaps, the measurements were significantly improved to within 2.2%. The dosimetric impacts of 1 and 2 mm air gaps were also verified with Monaco to be 13.3% and 27.9% higher, respectively, due to the electron return effect. Conclusions: A minimal amount of air around or within the OSLDs can cause measurement discrepancies of 10% or higher when placed in a high b‐field MR‐linac system. Care must be taken to eliminate the air from within and around the OSLD. [ABSTRACT FROM AUTHOR]

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The Veiki moraine in northern Sweden, a geomorphologically distinct landscape of ice-walled lake plains, has been interpreted to represent the former margin of an intermediate-sized pre-Last Glacial Maximum (LGM) Fennoscandian ice sheet, but its age is debated as either marine isotope stage (MIS) 5c or MIS 3. We have applied optically stimulated luminescence (OSL) and radiocarbon dating to four sites within the northern part of the Veiki moraine to establish its chronology. The radiocarbon ages provide only minimum ages and most OSL ages have low precision due to poor luminescence characteristics and problems with incomplete bleaching, leading to two alternative ages. In either case, the OSL dating places the Veiki moraine formation in MIS 3 (best estimate 56-39 ka). Sedimentation continued in the low-lying centers of some plateaus (ice-walled lake plains) during MIS 3 and during the Holocene, with a break during the Last Glacial Maximum when the area was ice covered. We speculatively constrain the broad timing further by relating the sequence of events to other climate records. We suggest that ice margin retreat to the west of the Veiki area took place during Greenland Interstadial (GI) 16.1 (58.0-56.5 ka) and that limited ice advances, which led to debris-covered ice margins in the Veiki zone, occurred during the following stadials GS-16.1 to 15.1 (56.5-54.2 ka). The GI-14 interstadial, which began 54.2 ka and lasted ~5.9 ka, could then be the period when the ice within the dead-ice landscape melted, first leading to ice-walled lakes and later to the inversed topography characteristic of the Veiki landscape. [ABSTRACT FROM AUTHOR]

Aeolian studies of Lake Michigan's coastal dunes have yet to elucidate what factors control their episodic activity over the past 5000 years. High lake levels exposing sand along with increased storminess is generally accepted for high perched dunes. This hypothesis, however, remains poorly tested for low perched dunes along the southeast Lake Michigan coastline. Here, small lakes in the lee of dune complexes contain aeolian sand and various biological proxies. Age and sedimentation rate models from Gilligan Lake cores guide analysis of aeolian sand, charcoal, pollen, and diatoms at high resolution (1 cm [10.4 yr/cm]) during the high-water Algoma Phase (3.1–2.4 ka) of the upper Great Lakes. The diatoms record a transition from a deep, more acidic lake to a shallower, more alkaline lake with fewer wetlands. This transition is accompanied by a stepped increase in the amount of aeolian sand. There is a weak correlation (R2 0.5, p < 0.01) between increasing abundances of charcoal chunks and sand. Peaks of sand follow peaks in charcoal threads and sheets, suggesting fire played a role in removing vegetation, presaging the landscape for increases in storminess. Arboreal pollen records a transition from a mesic forest Fagus - Acer - Quercus - Abies assemblage suggestive of moister conditions to one richer in mesic hardwoods tolerant of drier conditions. Together, the environmental proxy data record a shallowing lake concomitant with increasing aeolian sand, suggesting that drought-like conditions along the coastline conditioned the landscape for renewed aeolian activity. Once initiated, increased storminess and shoreline erosion maintained dune activity through increased sediment supply. [ABSTRACT FROM AUTHOR]

Loess–palaeosol sequences (LPS) represent important records of palaeoenvironmental dynamics throughout the Quaternary. During the Pleistocene's dry and cold phases, the Danube's riverbed was one of the major sources for loess sediments that built up LPS in southern Germany and southeastern Europe. Surprisingly, studies addressing Bavarian LPS along the Danube River often lack actuality. The Attenfeld site was one of them and is often cited as a typical LPS. Nevertheless, the site's previous interpretations are based on a few empirical data and field observations. Considering the site's closeness to the sediment's source area, the Alps, and the region's importance in Middle and Upper Palaeolithic migrational movements, those former renditions needed an evaluation. Therefore, we applied a multi‐proxy approach (including analyses of grain‐size distribution, element composition, and sediment colour attributes) combined with optically stimulated luminescence. Based on our findings, we conclude that the Attenfeld site's former interpretations might be too generalised. We identified units that were not mentioned by previous studies (e.g. Early Glacial dark greyish horizon). Field observations, sediment characteristics, and age estimates indicate sediment deposition of the dated units partly before MIS 4, which contrasts with previous interpretations. The results further demonstrate how sensitive LPS are to environmental settings and dynamics. [ABSTRACT FROM AUTHOR]

• The biopolymer STH can generate appropriate HU and has sufficient flexibility for use in a 3D printed motion phantom. • The correlation between the tumor and the thorax motion signal needs to be well defined. • The measurements by using OSL technique were observed to be close to the TPS results. The design, production and adaptability to clinical routine of a patient-specific tumor and respiratory monitoring phantom (TRMP) was investigated using 3D printer technology. TRMP and GTV modelling were done using 4D-CT images of the inhalation phase. The model was converted to STL (Stereolithography) format and printed with STH (Strong Herbal) biopolymer with HU (Hounsfield Unit) suitable for imaging purposes. The assembly of TRMP motorized parts and mechanical equipment has been completed and made suitable for clinical use. In the first part of the study, the deviations of radio-opaque markers attached to the TRMP sternum to perform mechanical quality control tests and T1-7 costal vertebrae in CC, AP, and LAT directions were evaluated. In the second part of the study, in order to evaluate the usability of the TRMP in quality assurance (QA), point dose measurements with BeO OSL dosimetry and EBT3 gafchromic film measurements were taken in Trilogy® radiotherapy accelerator and CyberKnife® robotic radiosurgery accelerator. In this study, we present a highly flexible TMRP capable of performing independent internal and external motions. TRMP was successfully tested in different treatment accelerators, both mechanically and dosimetrically. [ABSTRACT FROM AUTHOR]

When and how was the Tibetan Plateau (TP), one of the least habitable regions on Earth, occupied by humans are important questions in the research of human evolution. Among tens of Paleolithic archaeological sites discovered over the past decades, only five are considered coeval with or older than the Last Glacial Maximum (LGM, ∼27–19 ka). As one of them, the Siling Co site in the central TP was previously announced to be ∼40–30 ka based on radiocarbon dating and stratigraphic correlation. Given the loose chronological constraint in previous studies, we here re-examined the chronology of the Siling Co site with the optically stimulated luminescence (OSL) dating technique. Four sections from the paleo-shoreline at an elevation of ∼4,600 m in southeastern Siling Co were investigated, with stone artifacts found from the ground surface. Dating results of nine samples delineated the age of ∼4,600 m paleo-shoreline to be ∼10–7 ka (∼8.54 ± 0.21 ka in average). This age indicates that the Siling Co site is not earlier than the early Holocene, much younger than the former age. The revised age of the Siling Co site is consistent with the wet and humid climate conditions on the TP during the early Holocene.

Despite the fact that Beryllium oxide (BeO) has been suggested by several research groups as an alternative passive radiation detector and dosimetric material, various concerns about supralinear dose response features were raised for both thermoluminescence (TL) and optically stimulated luminescence (OSL) signals of this material. This paper presents a detailed dose response study on BeO, for two different experimental conditions, namely for (i) the TL signal following irradiation at room temperature (RT), 125 and 200 °C and (ii) the CW – OSL signal measured at three different measurement temperatures (RT, 100 and 220 °C), following two different preheating temperatures (Tpre = 100 and 220 °C). The selection of these temperatures is based on the TL glow curve structure for BeO. The analysis was performed using (a) the actual experimental luminescence signals which suffer thermal quenching, and (b) by using the reconstructed luminescence signals, after correcting for thermal quenching. Deconvolution was performed only for the OSL signals. Intense supralinearity features for both TL peaks and OSL components are reported. Reconstruction affects greatly the dose response features of all TL signals, enhancing supralinearity. The dose response linearity coefficient μ of the dominant OSL component C1 is found to be independent of the preheating temperature. This provides a strong argument for the fact that the charge associated with this component originates mainly from the trap responsible for the TL peak 3 in BeO with Tm beyond 300 °C. Based on our experimental results, the supralinearity features of BeO are attributed to competition for free electrons by electron traps. The results of the present study suggest that competition takes place during both the irradiation and heating stages of a dose response experiment in BeO. Finally, preheating at 220 °C and subsequent OSL measurement at 100 °C is highly recommended as the optimum configuration for BeO, not only for roughly linear dose response but also in order to minimize transfer effects.

Abandoned shorelines are an important archive used to constrain past fluctuations in the hydrological balance of lakes around the globe. Within Australia, the shorelines preserved at Lake George, NSW, form one of the few shoreline archives in the south‐east of the continent that record palaeoenvironmental conditions throughout the late Quaternary. Here, we examined and tested the lake‐level record for Lake George constructed in the 1970s by dating a well‐preserved shoreline sequence at Luckdale, on the lake's eastern shore, using single‐grain optically stimulated luminescence (OSL) dating. Ten stratigraphic units were identified, and these suggest a late Quaternary highstand for Lake George in MIS 3, with fluctuations superimposed upon an overall drying trend throughout MIS 2 and into the present. At Luckdale, the highest four shoreline‐associated units were deposited ~13 to 19 m above lake base and date to between 39 ± 2 and 29 ± 1 ka ago. Our study pushes back the timing of maximum lake depth at Lake George to at least MIS 3, rather than MIS 2. The overall drying trend is supported by similar reductions in both Riverine Plain fluvial activity and other associated lake‐level records from within the Murray basin. Highlights: Seventeen new single‐grain quartz OSL ages constrain the formation of abandoned shorelines at Luckdale on the eastern margin of Lake George, NSW, Australia. The deepest water levels and oldest shorelines recorded at Luckdale date to between 39 ± 2 and 29 ± 1 ka (late MIS 3) and have an elevation of between ~13 and 19 m above lake base. Our results support a ~37 m maximum lake highstand, not recorded at Luckdale, occurring >39 ka ago in MIS 3, rather than MIS 2. The lake level shows an overall drying trend from the MIS 3 highstand throughout MIS 2 and into the Holocene, as reflected in both river and lake records across the Riverine Plain. [ABSTRACT FROM AUTHOR]

• Porcelain-based materials were investigated using stimulated luminescence methods. • Luminescence dosimetric properties were examined. • The lowest detectable dose limits (LDDL) of the porcelain-based materials were studied. • Luminescence kinetic parameters of both TL and OSL signals were determined. In the present study, different porcelain-based materials including a sugar bowl, an ashtray, a porcelain breaker, an artificial dental implant, an electric fuse and the seal of a porcelain moneybox were investigated via thermally (TL) and optically stimulated luminescence (OSL). For this purpose, luminescence dosimetric properties such as TL and OSL curve shapes, reproducibility, bleachability, along with dose response features such as linearity and lowest detectable dose limits (LDDL) of these materials were compared. A feature that is sample-dependent deals with both quartz and mullite content of each porcelain paste, as it was indicated by XRD analysis. Three dominant peaks in TL glow curves were ubiquitously observed, and OSL decay curves formed in two components (C 1 and C 2) for all samples. It was determined that the LDDL for only two TL peaks (P1 and P2) seem acceptable for accidental retrospective dosimetry applications (0.9–2.2 Gy). On the other hand, the LDDL values obtained according to OSL analysis yielded more promising results in terms of accidental retrospective dosimetry applications as 0.3–0.4 Gy and 0.75–1.35 Gy for C 1 and C 2 components, respectively. TL peaks P1 and P2 indicate the majority of prevalent, if not universal, properties of stimulated luminescence. This latter universality could support an argument towards identification of these two TL peaks directly correlated to quartz mineral. On the other hand, TL P3 could be attributed to a contribution of more than one mineral, such as quartz, kaolinite and mullite, due to the lack of prevalence over all stimulated luminescence features. [ABSTRACT FROM AUTHOR]

Thermally stimulated luminescence (TSL), optically stimulated luminescence (OSL), and radio-photoluminescence (RPL) are radiation-induced luminescence phenomena, and they are widely used for radiation dosimetry today. Despite their successful applications, the R&D of conventional and new phosphor materials is still actively performed in a wide range of research fields from basic science to application. Although these phenomena are considered to be different, they share common physical processes such as the generation, trapping, and transfer of electronic charges. In order to have a deeper look into these phenomena, it is important to comprehensively characterize those of a single material. For this, we have constructed a prototype TSL/OSL/RPL automated and integrated measurement system (TORAIMS), and then the system performance has been studied. The system offers automated and integrated measurement of several different TSL, OSL, and RPL properties, and it is also designed to cover many different phosphor materials having a wide variety of spectroscopic properties. [ABSTRACT FROM AUTHOR]

Retrospective dosimetry is one of the important tools of incident dosimetry in unplanned circumstances of dose calculation. Accident dosimetry is the evaluation of the external/internal radiation dose of people exposed to radiation incidents by various dosimetry methods. Any object in the incident area could be used as a natural dosimeter. So far, different materials such as ceramic or porcelain products, building materials, electronic components (IC parts, sim card, transistors), watch glass and phone screen have been studied following this purpose. In this study; the usability of various porcelain-based and ceramic-based materials which are commonly found around is investigated via luminescence methods; the list includes a sugar bowl, an ashtray, an electric fuse, an artificial dental implant with and without polishing material, ceramic nail file, the seal of prayer and moneybox. For retrospective dosimetry purposes, the effects of the sample preparation process on the TL signal is studied. Moreover, the effect of the temperature (for example fire) the material was exposed to before the radiation incident on the OSL signal, thermal quenching, changes in the OSL luminescence signal in different excitation modes are investigated. In addition, with the use of research materials, a radiation incident scenario was directed and the incident dose was measured using the TL and OSL techniques. According to the results, it was found that all examined samples can be used as dosimetric materials for retrospective dose measurement in case of a radiation incident. While comparing the incident scenario dose values calculated by the TL method with the TLD100s placed at the incident scene, it could be concluded that there is a deviation smaller than 10% in the piggy bank and artificial dental porcelain samples. The results obtained from the OSL measurements showed a deviation smaller than 9% in the fuse porcelain sample and a deviation smaller than 14% in the ceramic nail file sample which were more relevant in comparison to the other samples' results. [ABSTRACT FROM AUTHOR]

This research note presents evidence for the oldest Middle Pleistocene Eastern Saharan human activity from the area referred to as the Eastern Desert Atbara River (EDAR), Sudan, which is currently threatened by gold mining. Preliminary results of multifaceted analyses indicate the activity of Homo sapiens during MIS 5 as well as Homo erectus during MIS 7–11 or earlier. [ABSTRACT FROM AUTHOR]

The wide spatial coverage of sand dunes in continental interiors makes the understanding of their activity and accumulation history valuable for palaeoenvironmental reconstructions and the interpretation of landscape evolution. Nevertheless, the study of aeolian landscape development at the million‐year timescale is hampered by the complex interaction of factors determining dune migration and the inherently self‐destructive nature of their chronostratigraphy, thus limiting the applicability of traditional dating methods. This study presents a standalone program that simulates aeolian transport based on luminescence‐derived chronologies coupled with numerical modelling of the accumulation of cosmogenic nuclides. This integrative approach to modelling the history of aeolian landforms reveals phases of emergence of aeolian sand into the landscape, and provides a data‐based scheme that facilitates the morphodynamical study of aeolian processes over multiple timescales and up to several millions of years. The application of the program for reanalysing previously reported data from the Australian Simpson Desert reveals multiple pulses of sand dispersion into central Australia at 3.8–3.4, 2.9–2.5 and 1.5–1 Ma, corresponding to pronounced changes in climatic conditions and landscape deformation events. The synchronicity of the results with the established environmental framework that would promote the production and aeolian distribution of sand exemplifies the applicability of process‐based modelling in constructing a timeframe of key landscape evolution events in arid environments by studying aeolian deposits. The dependence of the parameters used to determine environmental settings on sand transportation patterns additionally makes the program a powerful tool to further investigate the triggers and mechanisms of aeolian processes. [ABSTRACT FROM AUTHOR]

Many stone artifacts and Paleolithic sites can be found in Hanjiang River Valley, which is an important area of human activities. In particular, the discovery of flint artifacts has greatly enriched the understanding of the technical diversity of stone artifacts in this area. However, the lack of age data also hindered the follow-up research. On this basis, we investigated and excavated two Paleolithic sites (Huoshiwa and Houshanpo) in Shigu village of Danjiangkou Reservoir Area in 2019 and found dozens of flint artifacts. The standard quartz single-aliquot regenerative dose-based optically stimulated luminescence method was used to date the samples from two Paleolithic sites. The natural OSL signals of the cultural layer samples reached saturation, the ages given could be minimum. Results showed that the ages of the cultural layer in Houshanpo and Huoshiwa sites are older than 70 and 50 ka, respectively. Our study fills in the blank of absolute age of flint artifacts in Danjiangkou Reservoir Area in Late Pleistocene, and provides chronological support for the study of the flint Paleolithic technology. [ABSTRACT FROM AUTHOR]

This paper reports for the first time the in-depth study of thermoluminescence (TL) and optically stimulated luminescence (OSL) of Brazilian alexandrite pellets (BeAl 2 O 4 : Cr3+) previously exposed to X-rays. Firstly, structural and composition analysis of alexandrite powder was performed to verify the quality of the samples. X-ray diffraction (XRD) pattern revealed that the sample is composed by chrysoberyl (alexandrite) and minor phases as quartz, kaolinite and phlogopite. The presence of several elements, including Cr and Fe, was also detected by X-ray fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Alexandrite pellets exhibited an intense TL signal when previously irradiated with X-ray, showing from the deconvolution five glow peaks centered at 75, 130, 175, 250 and 300 °C. The activation energy (E) and frequency factor (s) were estimated using first-order and general-order kinetic equations. The deconvolution of the OSL curve for alexandrite fit reasonably into three components, characterized as fast, medium and slow. The results obtained showed that the OSL and TL signals of alexandrite pellets vary linearly as a function of the X-ray. The pellets have low fading at room temperature, maintaining 63% of the OSL signal after 10 days of sample storage. Overall, the results suggest that natural alexandrite has TL and OSL sensitivity to X-ray radiation, being a promising material to this radiation. • OSL and TL signal from alexandrite (BeAl 2 O 4 :Cr3+) pellets irradiated with X-ray was investigated. • The sample presented 5 TL glow curves with kinetic parameters similar to beta-irradiated sample. • It was possible to describe the OSL curves with 3 components: fast (C1), medium (C2) and slow (C3). • Alexandrite can be applied for radiation dosimetry with different types of radiation. [ABSTRACT FROM AUTHOR]

This study focuses on the sedimentological and stratigraphic description and chronology of Pleistocene coastal deposits on the Pityusic Islands (Balearic Islands, Spain). These deposits show evidence of interference between processes characteristic of alluvial, marine, and aeolian environments. Optically stimulated luminescence dating of aeolian levels indicates that deposition took place from the Lower to Upper Pleistocene. The sedimentological and chronological analysis of these deposits allows reconstruction of coastal Pleistocene environmental history from MIS 22 to MIS 2. The results show that changes in the average wind direction over time, modulated by the interaction with coastal relief orientation, were the main controls on the Lower to Upper Pleistocene coastal landscape evolution on the Pityusic Islands. The main episodes of aeolian activity identified in the Western Mediterranean, can be linked to periods of low sea level. The study's findings the presence of two dominant environments, coastal aeolian and alluvial, each characterized by distinct geological processes. Interestingly, these processes have led to the formation of deposits that exhibit a combination of characteristics from both environments. Moreover, these deposits retain elements inherited from each environment in terms of sedimentary supply, precipitation, runoff or aeolian transport. These results corroborated by OSL dating provide a useful indicator of the geomorphological processes and changes that occurred during the Pleistocene, unraveling the environmental evolution, and contributing to the growing knowledge on western Mediterranean aeolian or aeolian-alluvial interacting environments during the last 1000 ka. • The influence of glacioeustatic sea level variation on coastal landscape evolution in the Mediterranean basin. • Optically stimulated luminescence dating of the Pleistocene deposits of Pityusic Islands (MIS 22 to 2). • Arid and cold stages (glacial stages-lowstand periods) are represented by the development of the dune system. [ABSTRACT FROM AUTHOR]

The portable radio (hand-held device) is the preferred means of communication for the first responders from the homeland security forces and is systematically carried during intervention. This electronic device could therefore be a good candidate as a possible fortuitous dosimeter to estimate the dose received by the members of these security forces in the event of a radiological accident. For this purpose, the dosimetric properties of electronic components extracted from the circuit board of portable radios used by a French specialised intervention unit were investigated using the OSL technique. The dosimetric properties of such electronic components were compared to those of resistors extracted from mobile phones to determine whether an OSL protocol developed for mobile phone resistors could be applied also to these electronic components. The OSL dosimetric properties were generally similar and the results of a dose recovery test using these components removed from a portable radio were in good agreement with the nominal dose. Further experiments showed the importance of knowing the storage temperature conditions of these devices to accurately estimate the dose in case of a radiological accident. • Radiation accident dosimetry using electronic components from portable radios was considered. • Their OSL dosimetric properties were generally similar to those of mobile phone resistors. • An OSL protocol developed for mobile phone resistors was successfully applied for dose estimation. • In the event of a radiological accident, these components could be used as fortuitous dosimeters. [ABSTRACT FROM AUTHOR]

A negative relationship has been reported for the characteristic saturation dose (D 0) of the quartz optically stimulated luminescence (OSL) signal and the quartz grain size, of which the mechanism is still not understood. Here, the natural coarse-grained quartz samples (63–90 μm, 90–125 μm) are artificially ground into fine grains and the effect of alpha irradiation on the D 0 values of the ground fine grains is investigated. The ground fine grains (4–11, 11–45, 45–63 μm) have similar D 0 values as the coarse grains. Laboratory alpha irradiation is administered on the artificial 4–11 μm quartz fraction. The D 0 shows an increasing trend with the amount of alpha irradiation; meanwhile, the proportion of the fast OSL component decreases and the proportions of the medium and slow components increase with alpha irradiation. The higher D 0 after alpha irradiation may be a result of the higher proportion of electron traps related to the medium component. However, the increasing trend of D 0 stops when the alpha dose reaches a certain amount, and the degree of D 0 increase induced by alpha irradiation cannot fully account for the much higher D 0 values of the fine quartz grains in nature. • Natural quartz shows higher D 0 and higher proportion of the medium OSL component with smaller grain size. • Artificially ground fine-grained quartz has similar D 0 as the parental coarse-grained quartz. • Alpha irradiation can increase the D 0 and the medium component proportion, but with limited degree. [ABSTRACT FROM AUTHOR]

Offshore tsunami deposits have the potential to substantially improve our understanding of long-term tsunami hazard. This may be particularly true for the Portuguese Algarve coast, where onshore sediment records are restricted to the last 3000 years due to scarcity of sediment archives suitable for identifying tsunami deposits. This study investigates the potential of optically stimulated luminescence (OSL) for dating offshore tsunami layers from the Portuguese shelf and its background sedimentation cored during METEOR cruise M-152, by comparing luminescence ages with radiocarbon chronologies. Accurate luminescence ages for both offshore tsunami deposits and constraining shelf sediments can be achieved by using single grains of quartz in combination with the minimum age model. However, even single grain ages significantly over-estimate by several thousand years for some very poorly bleached tsunami deposits and underlying shelf sediments affected by erosion during the event. This demonstrates the necessity of using chronologies that are based on a large number of ages, as well as a combination of direct tsunami ages and limiting ages for background sedimentation. The combination of luminescence ages from this study with radiocarbon ages using a Bayesian approach yields an age of 3600–3800 years for a predecessor event of the 1755 CE Lisbon tsunami, formerly radiocarbon dated in the same offshore sediment cores to ca. 3600 cal years BP. • Direct quartz and feldspar luminescence ages for offshore tsunami deposits. • Evaluation of luminescence dating accuracy against radiocarbon chronology. • New age constraints for a prehistoric predecessor of the 1755 Lisbon tsunami. • Hiatus below event layers allow insights into erosive capacity of tsunami backwash. [ABSTRACT FROM AUTHOR]

K'gari in South East Queensland, Australia, is the world's largest sand island and a UNESCO World Heritage Area. The island is covered by extensive coastal dune fields that have been divided into seven morphological units (the Awinya, Yankee Jack, Bowarrady, Triangle Cliff, Freshwater, Station Hill, and Cape). Optically-Stimulated Luminescence dating of the dune sequences indicate that the Awinya unit is > 340 ka, and the Yankee Jack and Bowarrady units are ca. 180 ka old. Holocene dune sequences comprise Triangle Cliff (ca. 8.5 ka); Freshwater (ca. 4 ka); Station Hill (ca. 1.5 ka) and Cape (ca. < 0.5 ka). Combining these data with dune ages from the adjacent Cooloola Sand Mass, we demonstrate that for at least the last three glacial cycles the dunes were emplaced during intermediate to high sea-levels. At shorter time intervals (decades to centuries), some dune formation is affected by storminess. Initial formation of the dune field occurred in the mid-Pleistocene, but the most recent widespread stabilisation of dunes occurred late in Marine Isotope Stage 7 (MIS 7: 190–240 ka). The preservation of dunes relates to antecedent topography coupled with the duration and height of individual interglacial high sea-stands. This research confirms K'gari as an outstanding example of geomorphological processes and supports its World Heritage listing. • First chronology of all the major parabolic dune units on K'gari (formerly Fraser Island), the world's largest sand island. • The dune units are emplaced during intermediate to high sea-levels at least as far back Marine Isotope Stage 7. • A major Late Holocene scarp suggests that major cyclones can penetrate SE Queensland on occasions. [ABSTRACT FROM AUTHOR]

In response to the Indo-Asian collision, deformation of the Tien Shan initiated at ∼25 Ma along the northwestern margin of the Tarim Basin. 300 km north, the Kyrgyz Range began deforming ∼15 Ma later. Although multiple intervening structures across the Tien Shan are currently active, the sequencing of initial deformation across the orogen's entire width remains poorly known. To determine whether deformation migrated sequentially northward or developed less predictably, we documented deformation patterns within the Naryn Basin in south-central Kyrgyzstan. Detailed mapping and a published balanced cross section across the Naryn Basin suggest that deep-seated, relatively steeply dipping thrust faults have disrupted the basin during late Cenozoic deformation. Dating of deformed fluvial terraces with ages between ∼10 and 250 ka constrains the rate of deformation across relatively young structures in the Tien Shan interior. Based on geodetic surveys of dated terraces, local rates of relative rock uplift span from 0.3 to 3.5 mm/yr. Folding rates and patterns are temporally persistent at a given site. Moreover, they mimic modern geodetic rates measured from interferometric synthetic aperture radar. Extrapolating these rates into the past suggests that structures within the interior of the Naryn Basin formed in the last 1 Myr, whereas the ranges surrounding the basin initiated at least 1-4 Myr earlier. Hence, within the Naryn Basin itself, deformation has migrated from margins to interior. Similarly, these new chronologies indicate that at least some deformation in the interior of the Tien Shan initiated millions of years later than along either orogenic margin. ©2014. American Geophysical Union. All Rights Reserved.

In this study, the SrS nanopowder co-activated by Ce3+ and Sm3+ (SrS:Ce,Sm) was synthesized by the co-precipitation method. The transparent pellets were fabricated by mixing the SrS:Ce,Sm nanopowder and bisphenol-A epoxy resin as a crystal of the optically stimulated luminescence (OSL) dosimeter. The crystalline phase verification and also, the morphology of the synthesized nanopowder were investigated using the XRD patterns and FESEM images, respectively. The effects of Ce3+ and Sm3+ concentration and the Thioglycerol (as capping agent) concentration on the sensitivity of SrS:Ce,Sm OSL response were evaluated in the same exposure and measurement conditions. The obtained results demonstrated the optimum sensitivity of the OSL response of the samples to a test dose of approximately 0.4 mGy by X-ray irradiation, which was related to 0.02 and 0.01 mol% concentrations of Ce and Sm, respectively; the 0.1 M concentration of the Thioglycerol was associated with the nanocrystallite size of 24+2 nm as well

In this study, the validity of using the optically stimulated luminescence (OSL) technique as a scanning method for the detection of irradiated foodstuffs was investigated. Gamma-irradiated thyme, mint and clove samples were stimulated with a continuous wave blue light (CW-OSL) and their OSL signal sensitivity and stability properties were measured. While no OSL signal was observed for all non-irradiated spices, a significant increase in the intensity of OSL signals was noted for all samples after irradiation with 5 kGy, 10 kGy and 20 kGy. It was also observed that the measured OSL signals were well above the background level even after one year of irradiation. It is therefore concluded that irradiated thyme, mint and clove samples can clearly be identified using the CW-OSL technique without any pre-treatment even one year after irradiation. This result indicates that, where spices contain sufficient silicate minerals, the CW-OSL technique could be used as a method for detecting irradiation. [ABSTRACT FROM AUTHOR]

Studying the slip rate along major strike‐slip faults is critical to understanding the deformation and kinematics in continental collision zones. The Gyaring Co fault was previously regarded as a segment of the southern boundary of eastward extrusion in central Tibet, and its eastern segment was linked to the Xainza rift. However, the spatial distribution of its slip rates is poorly constrained, which limits our knowledge about how deformation is partitioned between strike‐slip and normal faults in central Tibet. Here, we used optically stimulated luminescence dating to determine the ages of displaced landforms (alluvial fans, lake shorelines, and river terraces) along the Gyaring Co fault. The results demonstrate a southeastward decrease in the late Quaternary slip rate from 2–3 mm/yr to 0.5–1.0 mm/yr over a distance of ∼130 km. Although the slip rate of the middle‐west segment of the Gyaring Co fault seems to have decreased slightly (20%) at ∼10 ka, it remained relatively stable during the late Quaternary. Regional analysis suggested that the Gyaring Co fault is kinematically compatible with the Xainza rift and probably has accelerated rift extension in its northern part since the middle Miocene. This northward‐increasing extension rate may accommodate more than half of the observed strain‐rate gradient along the Gyaring Co fault. The difference observed in strain rate requires a strain of ∼1 × 10−8 per year, comparable with the average present‐day strain rate of the Tibetan Plateau. The Gyaring Co fault separates the crustal blocks that are also deforming internally, suggesting distributed deformation in central Tibet. Key Points: Optically stimulated luminescence dating of displaced alluvial fans, lake shorelines, and river terraces allows us to determine slip rates along the Gyaring Co faultLate Quaternary slip rates of the Gyaring Co fault probably decrease southeastward from 2–3 to 0.5–1.0 mm/yrMore than half of the observed slip rate gradient may be accommodated by extension within the Xainza rift zone [ABSTRACT FROM AUTHOR]

We describe and analyze the Local Charged Particle Swarm Optimization (LCPSO) algorithm, that we designed to solve the problem of tracking a moving target releasing scalar information in a constrained environment using a swarm of agents. This method is inspired by flocking algorithms and the Particle Swarm Optimization (PSO) algorithm for function optimization. Four parameters drive LCPSO—the number of agents; the inertia weight; the attraction/repulsion weight; and the inter-agent distance. Using APF (Artificial Potential Field), we provide a mathematical analysis of the LCPSO algorithm under some simplifying assumptions. First, the swarm will aggregate and attain a stable formation, whatever the initial conditions. Second, the swarm moves thanks to an attractor in the swarm, which serves as a guide for the other agents to head for the target. By focusing on a simple application of target tracking with communication constraints, we then remove those assumptions one by one. We show the algorithm is resilient to constraints on the communication range and the behavior of the target. Results on simulation confirm our theoretical analysis. This provides useful guidelines to understand and control the LCPSO algorithm as a function of swarm characteristics as well as the nature of the target. [ABSTRACT FROM AUTHOR]

• Employee identity cards were investigated for emergency retrospective dosimetry. • The methodology for retrieval of the absorbed dose was developed using Single Aliquot Regenerative Dose. • The methodology was validated for different electronic cards with good precision. OSL dosimetric studies have been carried out on wired chip card modules from employee identity cards (ID cards) from a premier government research institution. The OSL dose response of chip card modules shows a linear behavior upto a dose of 20 Gy and thereafter exhibited a sub-linearity. The homogeneity of OSL signal among different cards as well as the repeatability studies were carried out and were found to be satisfying the requirements of IEC. The signal was found to be stable after 4 days of storage. In addition, dose recovery methodology was suggested for RFID chip card module and the same has been validated with different chip card modules. [ABSTRACT FROM AUTHOR]

The stratigraphic integrity of archaeological deposits in the seasonally wet tropics can be disrupted by termite activity and other processes. Significant questions have been raised about the surprisingly old age estimates for artefacts recovered from two sites in northern Australia: Nauwalabila and Madjedbebe. If accurate, a 65,000‐year date for the latter would represent a 30% increase in the currently accepted length of human occupation of the continent. The oldest estimate for Nauwalabila falls just short of that. These dates would have important implications for human dispersal across Eurasia in the Late Pleistocene. No other data from Australia support them. Smith et al. (2020) claim to refute the notion that termite disturbance accounts for these anomalies. Here we show that the criteria on which the assertion is based are invalid. Radiocarbon data from both sites, not cited by Smith et al. (2020), are consistent with the termite‐disturbance hypothesis. Luminescence data claimed to offer strong support for the early Madjedbebe estimate are also consistent with termite disruption. We conclude that the early dates for human presence at Madjedbebe and Nauwalabila must be rejected along with any chronometric inference about human behaviour to the degree it relies on them. [ABSTRACT FROM AUTHOR]

Background: Dosimetry in ultra-high dose rate (UHDR) electron beamlines poses a significant challenge owing to the limited usability of standard dosimeters in high dose and high dose-per-pulse (DPP) applications., Purpose: In this study, Al 2 O 3 :C nanoDot optically stimulated luminescent dosimeters (OSLDs), single-use powder-based LiF:Mg,Ti thermoluminescent dosimeters (TLDs), and Gafchromic EBT3 film were evaluated at extended dose ranges (up to 40 Gy) in conventional dose rate (CONV) and UHDR beamlines to determine their usability for calibration and dose verification in the setting of FLASH radiation therapy., Methods: OSLDs and TLDs were evaluated against established dose-rate-independent Gafchromic EBT3 film with regard to the potential influence of mean dose rate, instantaneous dose rate, and DPP on signal response. The dosimeters were irradiated at CONV or UHDR conditions on a 9-MeV electron beam. Under UHDR conditions, different settings of pulse repetition frequency (PRF), pulse width (PW), and pulse amplitude were used to characterize the individual dosimeters' response in order to isolate their potential dependencies on dose, dose rate, and DPP., Results: The OSLDs, TLDs, and Gafchromic EBT3 film were found to be suitable at a dose range of up to 40 Gy without any indication of saturation in signal. The response of OSLDs and TLDs in UHDR conditions were found to be independent of mean dose rate (up to 1440 Gy/s), instantaneous dose rate (up to 2 MGy/s), and DPP (up to 7 Gy), with uncertainties on par with nominal values established in CONV beamlines (± 4%). In cross-comparing the response of OSLDs, TLDs and Gafchromic film at dose rates of 0.18-245 Gy/s, the coefficient of variation or relative standard deviation in the measured dose between the three dosimeters (inter-dosimeter comparison) was found to be within 2%., Conclusions: We demonstrated the dynamic range of OSLDs, TLDs, and Gafchromic film to be suitable up to 40 Gy, and we developed a protocol that can be used to accurately translate the measured signal in each respective dosimeter to dose. OSLDs and powdered TLDs were shown to be viable for dosimetric measurement in UHDR beamlines, providing dose measurements with accuracies on par with Gafchromic EBT3 film and their concurrent use demonstrating a means for redundant dosimetry in UHDR conditions., (© 2023 American Association of Physicists in Medicine.)

Background and Aim: Today, OSL (Optically Stimulated Luminescence) dosimetry system based on optical stimulation, includes systems that can meet many requirements for radiation protection in the field of medicine and space. The Calcium Sulfide (CaS) is one of the earthchr('39')s alkaline sulfide materials which can be used as a detector in this system. In this research, some of the dosimetry properties of CaS doped with Cerium, (Ce), and Samarium, (Sm) elements were investigated as OSL dosimeter sensor. Materials and Methods: First, attenuation of x-rays through the sensors were analyzed and the absorbed dose rate was evaluated using MCNP code. After calcium sulfide tablets were fabricated and their concentration optimized, the maximum waiting time prior to readout was obtained. In addition, the repeatability and linear response of the detector were determined as a function of CaS concentration. Results: Eight minutes after radiation exposure of detectors, the detection output signals became stable. This stability was monitored for at least 30 minutes after irradiation. The repeatability in measurements was observed within the dose ranges of 100 to 860 mGy. The dosimeter response was observed linear over this dose ranges. Conclusion: According to the above-observed results and statistical evaluations, one can conclude that the CaS:Ce,Sm crystal is a proper sensor for OSL dosimeter systems in medicine and space studies.

Westerlies‐dominated arid central Asia (ACA) has a very fragile ecological environment that highly depends on the available moisture sources. However, the moisture history of this region during the Holocene has been a controversial topic for several decades. Here, we performed optically stimulated luminescence (OSL) dating and grain‐size analysis of aeolian sediments from the eastern Balikun Basin. Our results demonstrated that the early Holocene climate in the Balikun Basin was dry (before ~6.5 ka) and then became wetter during the mid–late Holocene. This Holocene climate pattern correlates well with other climatic inferences from various proxies acquired at various ACA locations, further supporting an earlier view that the Holocene climate in ACA was out of phase with that of the East Asia summer monsoon. Furthermore, an extremely dry event at 4.3–2.6 ka correlated well with pollen records and a decrease of ~4°C in temperature in the western Balikun Lake, but this event was not evident in other ACA regions. Finally, Mingsha Shan Sand Dunes in the eastern Balikun Basin initially accumulated in the earliest Holocene. We suggest that the early Holocene dry climate in the ACA region and the local geomorphology are responsible for the formation of the Mingsha Shan Sand Dunes. [ABSTRACT FROM AUTHOR]

Wallington in central Northumberland is a late seventeenth- and early eighteenth-century country house with associated pleasure grounds. Much of the surrounding estate is agricultural land, though there are also expanses of moorland and conifer plantation. The character of Wallington's landscape, now divided into fifteen separate farm holdings, was to a large extent shaped by estate management practices and improvements in the eighteenth– nineteenth centuries. Today's settlement pattern is made up largely of dispersed farmsteads, with field systems which reflect the orderly rectilinear layout of planned enclosure, being separated mainly by long and fairly straight stonefaced banks. In medieval and early modern times, by contrast, the landscape is thought to have been quite different, with nucleated villages set amidst irregular open fields which were farmed collectively. The process of long-term landscape change from open to enclosed field systems has been inferred across the whole of Northumberland but it can be difficult to understand in detail. Absolute dating evidence for field systems before the eighteenth century is generally lacking and the origins and development of historic earthworks including boundary banks and the remains of arable farming are poorly understood. This paper presents results of research which used retrogressive landscape analysis (based on documentary evidence, archaeological data, aerial photographs, and historic cartography) to identify five areas for detailed geoarchaeological investigation and sampling with optically stimulated luminescence profiling and dating (OSL-PD). The results provide new perspectives on the development of landscape character at Wallington which have wider relevance for north-east England and beyond. [ABSTRACT FROM AUTHOR]

Optically stimulated luminescence (OSL) signal properties of pellets from three types of NaCl (two household salts and one analytical grade salt) were investigated for their use in prospective dosimetry. Special attention was given to the OSL signal behaviour with time. The readout protocol was optimised in terms of preheat temperature, and the OSL signal yield of the NaCl pellet with time as well as the fading of the OSL signal with time was investigated. The effects of acute and chronic irradiations were compared. Irradiations and readout were performed using a Risø TL/OSL reader (TL/OSL-DA-15, DTU Nutech, Denmark). The optimal preheat temperature was determined to be 100 ºC, yielding OSL signals similar to a 1 h pause before OSL signal readout. There was no OSL signal fading observed as a function of time, but a decrease in the OSL signal yield of the NaCl pellets with time resulted in an apparent inverse fading when converting the OSL signal to an absorbed dose. For chronic radiation exposures of up to five weeks, the sensitivity of the NaCl pellets was found to be stable. The results of this study show that the use of NaCl pellets for prospective dosimetry is a promising, cost-effective, and accessible complement to commercially available alternatives for accurate absorbed dose determinations. [ABSTRACT FROM AUTHOR]

The timing of high lake‐level stands during the Late Pleistocene in western China remains controversial. Here we report new results from Megalake Tengger based on a study of palaeo‐shorelines and a drill core from Baijian Lake in the northwestern Tengger Desert. Multiple dating methods, based on luminescence signals (quartz optically stimulated luminescence, K‐feldspar post infrared‐infrared stimulated luminescence) and electron spin resonance signals of quartz, were used to date beach sands from palaeo‐shoreline profiles at altitudes of ~1310 m (+20 m above lake level), ~1320 m (+30 m) and ~1350 m (+60 m), and from the top 20 m of sandy sediments from the drill core obtained from the modern beach of Baijian Lake. The dating results show that high lake‐level stands associated with the previously reported Megalake Tengger (~1310–1320 m) occurred during the late Early to Middle Pleistocene, which is much earlier than previously reported. In addition, no geomorphological evidence of shorelines and sedimentary evidence from the drill core profile were found to support the previously reported Late Pleistocene lake levels. Our results indicate that the exact age of the previously reported 'high lake level event' in a large part of northwestern China during the Late Pleistocene needs to be re‐evaluated. [ABSTRACT FROM AUTHOR]

Calcium sulphate (CaSO 4) geological material is the main constituent of art objects and geological formations, mostly in the form of gypsum. Nevertheless, investigations of either optically or infrared stimulated luminescence (OSL or IRSL respectively) properties are scarce for this material towards age assessment applications. The present work studies for both IRSL and OSL signals of CaSO 4 (a) the effect of the preheating to the sensitivity, towards selecting the optimum preheating conditions, (b) the bleaching ability of both signals via the corresponding residual TL signal levels, towards selecting the appropriate stimulation duration and (c) whether mixing with water acts as a zeroing mechanism for these signals. IRSL and OSL yield different sensitization threshold temperatures, being 250 °C or 300 °C, depending on the water content of the mineral (hemihydrate, anhydrous and the most usual dihydrate). However, for the cases of protocols involving either a single IRSL measurement or post IRSL OSL measurements, preheating temperature should not exceed 225 °C. The optimum stimulation duration is 100 s for the blue OSL and 60 s for the IRSL. Finally, mixing with water affects (i) insignificantly the zeroing of IRSL signal in anhydrites, (ii) partially the zeroing of OSL in all groups and (iii) substantially the zeroing of IRSL signal in gypsum and bassanite. [ABSTRACT FROM AUTHOR]

• LCAF is studied for OSL dependence on temperature in the range of 100–260 °C. • A generic protocol has been suggested to conduct temperature dependent studies. • Residual TL is used to assess the effectiveness of depletion of charge carriers. • Different heating rates were used to establish any thermal quenching. Studies were carried out to investigate the temperature dependence of OSL in LiCaAlF 6 : Eu, Y phosphor (LCAF). The generic protocol and methodology for conducting such studies has been suggested. The material is investigated in the temperature range of 100–260 °C. The residual TL after various sequences is used as a probe to investigate the effectiveness of thermal and optical stimulation in releasing trapped charges. It is found that the simultaneous application of thermal and optical stimulation results in more efficient and faster depletion of signal in comparison to the sum of thermal and optical stimulations alone when carried out in isolation. Thus, simultaneous application of temperature and optical stimulation lead to increased synergistic effect in terms of acquisition of luminescence signal. [ABSTRACT FROM AUTHOR]

We evaluate the paraglacial activity in Nexpayantla, a subtropical mountainous gorge in Popocatépetl volcano (Central Mexico), fully deglaciated in the 20th century. Glacial advances are evidenced by the presence of moraines. Fluvio‐glacial terraces and an alluvial megafan resulted from the gorge deglaciation. Current reworking of the glacigenic material is done by landslides and debris flows produced on the moraines and terraces. To study the different phases of mobilization of glacigenic sediment, we used an approach based on the study of the optically stimulated luminescence (OSL) signals obtained from a portable OSL (POSL) reader in samples extracted from both glacigenic and paraglacial deposits. The luminescence (POSL) results obtained at moraines increase as altitude decreases, which is expected for deglaciated valleys where the oldest moraines are located at lower elevations. We evaluate the grade of luminescence signal reset of the glacigenic sediments during the proglacial stage, and the subsequent deglaciation phases. Our results indicate that there is a marked transition between glacial and fluvially dominated processes at Nexpayantla Gorge. We find that the grade of luminescence signal resetting in the paraglacial deposits is a good indicator to trace paraglacial stages and the beginning of exhaustion of the paraglacial activity in mountain areas. OSL ages confirm that the oldest fluvio‐glacial terraces found at the middle sector of Nexpayantla Gorge are ~2 ka, which is also supported by an AMS 14C age. OSL dating was found challenging, since quartz grains have low sensitivity because of their volcanic origin; POSL signals, however, are in good agreement with the location and distribution of geomorphic markers. We propose that luminescence data obtained from the POSL unit can be useful to provide information about sediment mobilization in paraglacial environments during different climatic pulses – even for the case where mineral grains have low sensitivity, such as in volcanic sediments. © 2020 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper is intended as a compendium of good practices to assess whether luminescence dating can provide researchers with valuable chronological information for ceramic samples. It is organized into two main sections. The first section provides an introduction to luminescence dating, including its physical principles, the applied measurement procedures, and a brief summary on a new dating technique (RHX) not based on luminescence. This section aims to provide non-specialists with a background on the physical principles underlying luminescence dating, in order to enable an understanding of the issues that may affect the reliability of luminescence ages and a critical assessment of the results from luminescence laboratories. The second section presents a series of case studies which illustrate the use of these methods, how they can be applied, and what results can be obtained. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]