Quaternary Geochronology最新文献

{"title":"Single-grain luminescence dating of K-feldspar based on the pre-dose MET-pIRIR protocol","authors":"Ting Cheng ,&nbsp;Bo Li ,&nbsp;Dongju Zhang","doi":"10.1016/j.quageo.2025.101709","DOIUrl":"10.1016/j.quageo.2025.101709","url":null,"abstract":"<div><div>Potassium-rich feldspar (K-feldspar) is widely used in luminescence dating due to its high saturation dose, allowing the determination of ages for older sediments. Previous studies have shown that the ‘sensitivity’ of the post-infrared infrared stimulated luminescence (pIRIR) signal can retain a ‘memory’ of the pre-dose received but can be reset by sunlight bleaching. Building on the development of multi-aliquot and single-aliquot pre-dose multi-elevated-temperature post-IR IRSL (pMET-pIRIR) procedures, we investigate the performance of the single-aliquot regenerative-dose (SAR) pMET-pIRIR procedure for K-feldspar at the single-grain level. Solar bleaching experiments demonstrate that the sensitivity of the IRSL and MET-pIRIR signals can be effectively reset by a 3 h solar simulator bleaching step applied after each regenerative cycle. Integrating the SAR pMET-pIRIR procedure with the standardised growth curve (SGC)-based L_nT_n method successfully overcomes sensitivity carry-over, mitigates anomalous fading, extends the dating range and improves measurement efficiency for K-feldspar luminescence dating. Equivalent doses (D_e) can be determined using the sensitivity-corrected signal (L_x/T_x), regenerative signal (L_x) and test dose signal (T_x), providing flexibility across different dose ranges and improving dating reliability through cross-validation. Application to three sediment samples from China, including samples with independent known ages, confirms the method's ability to obtain accurate D_e values up to ∼1600 Gy (∼440 ka), with the potential to date samples approaching ∼1 Ma using the L_x and T_x signals. The single-grain SAR pMET-pIRIR method offers a promising approach for dating older sediments and investigating heterogeneous luminescence behaviours among grains or post-depositionally disturbed deposits.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"91 ","pages":"Article 101709"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maximum spacing estimation of chronological boundaries in discrete and uncertainty-prone age sequences","authors":"Shi-Yong Yu","doi":"10.1016/j.quageo.2025.101697","DOIUrl":"10.1016/j.quageo.2025.101697","url":null,"abstract":"<div><div>Estimating the endpoints of age sequences is a crucial task in archaeological and geological sciences. Here we advance this process by addressing three major limitations in previous approaches. First, we introduce a maximum spacing estimation method to simplify the conventional maximum likelihood estimation approach. Second, we apply Monte Carlo simulations to account for uncertainties in laboratory-derived ages. Third, we utilize a range of probability distributions to manage sampling variability, improving the accuracy and reliability of chronological inferences. This method is versatile, applicable not only for estimating settlement time from smaller datasets but also for determining the timing of rise and fall of cultures from larger datasets. Rigorous testing on both simulated and real-world chronological data demonstrates the practical utility and robustness of this method in handling discrete and uncertainty-prone age sequences. Comparative analysis shows that different statistical models significantly impact the estimation of chronological boundaries. Uniform and exponential models provide more constrained estimates with higher confidence, while normal and log-normal models introduce greater uncertainty. These wider intervals may reflect underlying uncertainties, such as stratigraphic variability or mixed-age samples, which restrictive models may overlook. We also highlight the sensitivity of age sequence estimates to data size, with important implications for interpreting the temporal boundaries of archaeological and geological events. Therefore, researchers are encouraged to carefully assess the nature and frequency distribution of their chronological data before considering the narrower estimates from uniform and exponential models as well as the broader intervals from normal and log-normal models to build more reliable chronological frameworks.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"91 ","pages":"Article 101697"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"‘Mammothfluidics’: Amino acid dating of fossil mammal tooth enamel using a modular microfluidic system","authors":"Laila Patinglag ,&nbsp;Marc R. Dickinson ,&nbsp;Marcus Hill ,&nbsp;Kirsty E.H. Penkman ,&nbsp;Kirsty J. Shaw","doi":"10.1016/j.quageo.2025.101705","DOIUrl":"10.1016/j.quageo.2025.101705","url":null,"abstract":"<div><div>Dating fossil samples helps reconstruct evolutionary history, aiding conservation efforts and mitigating climate change impacts. Amino acid geochronology of tooth enamel using the intra-crystalline protein decomposition (IcPD) approach allows direct dating of mammal teeth over Quaternary timescales (∼2.5 million years), beyond the limits of radiocarbon dating (∼50,000 years). However current methods require specialist equipment and relatively lengthy processing times. We developed a modular microfluidic system for chiral amino acid analysis of tooth enamel samples, consisting of three sequential glass microfluidic devices for sample bleaching, release of hydrolysable amino acids, and biphasic separation. Relative concentrations and D/L values of key amino acids were measured using reverse-phase high performance liquid chromatography (RP-HPLC). The microfluidic method reduced sample amounts from ∼15 mg to ∼1 mg and bleaching time from 72 h to 2 h. Amino acid compositions of modern and fossil samples were similar between the microfluidic approach and standard IcPD method, with good agreement up to D/L values ∼0.5 for phenylalanine (Phe) and glutamic acid (Glx). The method worked successfully across various genera and operators, with reduced sample mass and analysis time. This approach results in less destructive sampling of precious fossil samples and enables preparation steps in non-specialist labs, potentially allowing IcPD dating within the fossils’ country.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"91 ","pages":"Article 101705"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145121226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Luminescence dating of glacigenic deposits from northern Germany: A comparison of multigrain aliquots and single grains K-feldspar methods","authors":"Neda Rahimzadeh ,&nbsp;Niklas von Soest ,&nbsp;Sumiko Tsukamoto ,&nbsp;Jutta Winsemann","doi":"10.1016/j.quageo.2025.101711","DOIUrl":"10.1016/j.quageo.2025.101711","url":null,"abstract":"<div><div>Glacigenic sediments are challenging to date with luminescence dating technique, particularly with regard to resetting of the luminescence signal before sediment deposition. In this study, six samples from four different ice-marginal positions in northern Germany were investigated to test different luminescence dating methods that account for heterogeneous bleaching of meltwater deposits. Multigrain measurements exhibited agreement between fading corrected infrared stimulated luminescence (IR) and fading corrected post-infrared IR measured at 225 °C (pIRIR₂₂₅) ages, suggesting the studied samples were likely well bleached, as these signals bleach at different rates. Single-grain measurements showed a high proportion of saturated grains (up to ∼33 %) in these samples. The single-grain results were therefore assessed using conventional single-grain analyses and the <em>L</em>_n<em>T</em>_n method. Accurate estimation of the overdispersion (OD) of a well-bleached grain population (<em>σ</em>_b) is essential for applying statistical age models. Because no suitable well-bleached analogue sample with comparable burial doses was available, <em>σ</em>_b was estimated by combining intrinsic OD (from dose recovery tests) and extrinsic OD in quadrature. Both <em>D</em>_e and <em>L</em>_n/<em>T</em>_n OD values exceeded the derived <em>σ</em>_b values, confirming that all studied samples are poorly bleached and that the Minimum Age Model (MAM) is required. MAM ages derived from conventional single-grain and <em>L</em>_n<em>T</em>_n approaches are generally consistent; however, standard MAM ages tend to be slightly younger than <em>L</em>_n<em>T</em>_n MAM ages, likely due to truncation of the <em>D</em>_e distribution through the exclusion of saturated grains. These finding demonstrate that (1) consistent IR₅₀ and pIRIR₂₂₅ ages cannot be considered a reliable indicator of well-bleached samples, and (2) <em>σ</em>_b and overdispersion values should be determined and interpreted carefully, especially for old samples with a large number of saturated grains. We recommend applying the <em>L</em>_n<em>T</em>_n method at the single-grain level when dating partially-bleached samples with grains close to saturation, to obtain more reliable luminescence ages.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"91 ","pages":"Article 101711"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145519895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-method luminescence dating of late Cenozoic northern Upper Rhine Graben fluvial sediments","authors":"Anna-Lena Geis ,&nbsp;Mariana Sontag-González ,&nbsp;Thomas Kolb ,&nbsp;Mayank Jain ,&nbsp;Markus Fuchs","doi":"10.1016/j.quageo.2025.101689","DOIUrl":"10.1016/j.quageo.2025.101689","url":null,"abstract":"<div><div>The Upper Rhine Graben (URG) contains one of the most continuous sequences of unconsolidated Plio-Pleistocene sediments in central Europe. In order to understand the driving factors behind the sedimentation and erosion processes of the river Rhine fluvial system as well as the geological evolution of the rift system during the Quaternary and beyond, numerical dating of the sediments is indispensable. In 2020 and 2021, the Hessian State Agency for Nature Conservation, Environment and Geology (HLNUG) carried out a new continental drilling project near Riedstadt-Erfelden in Hesse, Germany, to obtain further information on the development of the northern part of the URG. Here, we present geochronological information derived from a multi-method luminescence dating approach of samples from the upper section of the core. Preliminary results from optically stimulated luminescence (OSL) of quartz and infrared-radiofluorescence (IR-RF) of K-feldspar are complemented by new measurements using infrared-stimulated luminescence (IRSL), post-infrared-IRSL (pIRIR) and infrared photoluminescence (IRPL). The latter is a relatively novel approach with the usage of a potentially non-fading and non-destructive signal from K-feldspar. For the first time, we apply a multiple elevated temperature (MET)-pIRIR-IRPL single aliquot regenerated dose (SAR) protocol on fluvial samples and present fading rates for the IRSL and IRPL signals derived from the protocol. We find that IRPL ages agree generally well with Middle Pleistocene luminescence ages of previous studies and biostratigraphic data while showing negligible fading and less sensitivity to a varying test dose. OSL ages up to ∼65 ka match phases of aggradation reported in earlier studies. Although IRPL and IR-RF ages are thought to arise from the same dosimetric trap, discrepancies in ages observed from both signals could be due to the required difference in sensitivity correction methods, though we note that as the signals approach saturation, the ages from both methods converge (&gt;200 ka). The pIRIR₂₂₅ and pIRIR₂₉₀ ages generally overestimate OSL and IRPL ages. Fading correction of IRSL₅₀ ages was not successful as they still underestimate quartz ages. Our results indicate an Elsterian-Holsteinian (MIS 12-11) to late Weichselian (MIS 2) age of the Mannheim formation and a Cromerian (MIS 13–21) deposition of the Ludwigshafen formation.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"90 ","pages":"Article 101689"},"PeriodicalIF":1.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of data reduction on classical and Bayesian 210Pb dating models","authors":"Marco A. Aquino-López ,&nbsp;Nicole K. Sanderson ,&nbsp;Maarten Blaauw ,&nbsp;Joan-Albert Sanchez-Cabeza ,&nbsp;Ana Carolina Ruiz-Fernández ,&nbsp;J. Andrés Christen","doi":"10.1016/j.quageo.2025.101687","DOIUrl":"10.1016/j.quageo.2025.101687","url":null,"abstract":"<div><div>Accurate dating of sediment layers is vital for deciphering Earth’s environmental history. This study addresses the precision and accuracy of lead-210 (²¹⁰Pb) dating models, a critical tool in sedimentary research for understanding environmental changes. Traditional Constant Rate of Supply (CRS) methods, while widely used, often struggle with accuracy, particularly in complex sedimentation scenarios. We contrast the CRS model with Plum, an advanced Bayesian approach, using simulated ²¹⁰Pb profiles derived from varied sedimentation processes. Our analysis reveals that even under ideal CRS conditions, the model’s precision does not significantly improve with additional data. In the contrary, Plum consistently outperforms CRS in both accuracy and precision, even with limited data inputs. As data volume increases, Plum’s performance improves markedly, unlike CRS. The Bayesian framework effectively addresses the complexities overlooked by CRS, demonstrating its superiority in refining sediment chronologies. This paper highlights the importance of incorporating statistical advancements in sediment dating techniques. By applying refined Bayesian methods like Plum, researchers can achieve more reliable sediment chronologies, essential for robust environmental studies and unravelling complex climate histories. Our findings suggest that embracing statistical innovations in geochronology can substantially enhance our understanding of Earth’s environmental changes.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"90 ","pages":"Article 101687"},"PeriodicalIF":1.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The challenges of direct dating of fossil teeth from the Australopithecus africanus, Taung Child type site, South Africa","authors":"Wenjing Yu ,&nbsp;Andy I.R. Herries ,&nbsp;Renaud Joannes-Boyau","doi":"10.1016/j.quageo.2025.101696","DOIUrl":"10.1016/j.quageo.2025.101696","url":null,"abstract":"<div><div>This paper presents the analyses of Combined Uranium Series and Electron Spin Resonance (US-ESR) dating on enamel fragments from five fossil teeth from the Hrdlička Pinnacle of the <em>Australopithecus africanus</em> Type Site at the Buxton-Norlim Limeworks, near Taung, South Africa. The mammal teeth were recovered from two types of deposits, the <em>A. africanus</em> bearing Pink Claystone (PCS) deposit that formed as layers within the Thabaseek tufa, and the secondary Yellow Red Sandstone (YRSS) deposit that filled cavities eroded through the tufa and PCS. The teeth were dated using enamel fragments following the US-ESR procedure. Two software programs, USESR (Shao et al., 2014) and DATA (Grün et al., 1988) were employed for the age estimation, however, the USESR software encountered numerous challenges, especially in modelling uranium uptake history. This is the first attempt to date a Late Pliocene to Early Pleistocene tufa deposit using US-ESR dating. The complicated history, poor preservation of the samples, and the diagenetic process in the fossil teeth samples make the dating very challenging. Especially as all samples suffered from uranium leaching and three of the five samples had high uranium concentrations in the enamel. This appears to be related to the nature of the tufa environment where high uranium concentrations have also been identified in secondary flowstones formed in caves within the tufa deposits. The final age estimate for the PCS deposits, contemporary with the Taung skull, is a minimum of approximately 2.4 Ma, based on the EU model. Similarly, a minimum age of approximately 1.8 Ma is estimated for the YRSS deposits. The USESR ages (∼2.0 Ma for the PCS deposit and ∼1.3 Ma for the YRSS deposit) were less preferred due to being derived using an extrapolation function. Nevertheless, all results are associated with many uncertainties and complexities and it should be approached with great caution. Another possibility is that the deposit might be challenging to date using the USESR method. The difficulties of dating old sites like Taung in South Africa and in particular tufa environment have been highlighted.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"90 ","pages":"Article 101696"},"PeriodicalIF":2.5,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstructing the Holocene volcanic past of El Hierro, Canary Islands","authors":"C. Prieto-Torrell ,&nbsp;J.L. Fernandez-Turiel ,&nbsp;A. Rodriguez-Gonzalez ,&nbsp;M. Aulinas ,&nbsp;E. Beamud ,&nbsp;M.C. Cabrera ,&nbsp;C. Criado ,&nbsp;H. Guillou ,&nbsp;P. Vidal-Matutano ,&nbsp;F.J. Perez-Torrado","doi":"10.1016/j.quageo.2025.101685","DOIUrl":"10.1016/j.quageo.2025.101685","url":null,"abstract":"<div><div>We present a geochronologic study with unprecedented detail from 42 Holocene subaerial volcanic edifices of El Hierro Island, Canary Islands. The study of new and published K-Ar, ⁴⁰Ar/³⁹Ar, ¹⁴C, and paleomagnetic ages, constrained by stratigraphic, geomorphic, and anthracological criteria, significantly improves the geochronologic framework of the Holocene volcanism at El Hierro. Our combined experiments show that radiocarbon and paleomagnetic dating were the best methods to determine this young volcanism's age. Indeed, small amounts of ⁴⁰Ar∗ detected in most dated samples do not allow for calculating geologically significant ages. The preliminary anthracological study of charcoals is recommended before ¹⁴C dating. Thirty-six eruptive events (86 % of the total) were retained for the geochronological model developed with ChronoModel combining radiocarbon and paleomagnetic and using the Bayesian inference. Seventeen eruptions were dated for the first time. The Holocene eruptive activity at El Hierro exhibits significant variability over time, with recurrence intervals ranging from 34 to 1078 years. The most recent subaerial eruptions were Lomo Negro, 1412 [1560, 1242] cal BP (MAP, mode of the posterior distribution, and 95 % highest posterior density (HPD) interval) and Montaña del Tesoro, 1059 [1206, 967] cal BP. In addition, historical records suggest possible submarine eruptions in 1721, 1777, and 1793, as well as the more recent and well-documented Tagoro volcano submarine eruption (2011–2012 CE). This recent low recurrence subaerial volcanic activity is unusual for an oceanic volcanic island in the juvenile shield growth stage. The volcanic edifices resulted from hybrid Strombolian monogenetic eruptions with alternating or simultaneous emission of pyroclastic tephra and lava flows. The absence of lava flows in the eruptions of the highest part of the island's summit is worth noting. This volcanic activity focused on the three rifts that configure the tetrahedral shape of the island, although the NW rift concentrated 50 % of the eruptions. These results contextualize the volcanic hazard of El Hierro in the face of eventual future eruptions.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"89 ","pages":"Article 101685"},"PeriodicalIF":1.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing robust lake sediment chronologies using 210Pb, Pu and radiocarbon dating of pollen concentrates and macrofossil: A case study from Lake Surprise, Victoria, Australia","authors":"Asika Dharmarathna ,&nbsp;Haidee Cadd ,&nbsp;Cameron Barr ,&nbsp;Alexander Francke ,&nbsp;Quan Hua ,&nbsp;David Child ,&nbsp;Michael Hotchkis ,&nbsp;Atun Zawadzki ,&nbsp;Patricia Gadd ,&nbsp;Chris Turney ,&nbsp;Christopher E. Marjo ,&nbsp;John Tibby ,&nbsp;Jonathan J. Tyler","doi":"10.1016/j.quageo.2025.101686","DOIUrl":"10.1016/j.quageo.2025.101686","url":null,"abstract":"<div><div>The development of reliable sediment chronologies is crucial for accurate interpretations of decadal to century-scale palaeoenvironmental changes in the late Quaternary. Although radiocarbon dating of sedimentary sequences is commonly undertaken, not all the organic fractions are representative of atmospheric ¹⁴C levels, resulting in inaccurate age models. Whilst terrestrial plant macrofossils are widely considered ideal dating material – assuming they are contemporaneous with the horizons being dated – they are often sparse or absent. In this context, radiocarbon dating of pollen extracts is increasingly being used as alternative dating material. Here, we used pollen radiocarbon dating, alongside a suite of macrofossil and bulk sediment dates, to develop a chronology for the Holocene sediments of Lake Surprise, in Victoria, Australia. ²¹⁰Pb activity and Plutonium (Pu) concentrations and isotope ratios were also analysed to constrain the age of the uppermost sediments, augmented with recent historical markers, including the first arrival of <em>Pinus</em> pollen and the date of an earlier coring expedition at the site in 2004. With respect to the radiocarbon dates, we found an age offset between the plant macrofossils and bulk sediment dates of 260 ± 86 ¹⁴C years and an offset of ∼340 ¹⁴C years between plant macrofossil and pollen extracts. In both cases, macrofossil dates appeared to be “younger” than the bulk sediment and pollen dates. The offset between pollen and plant macrofossil dates was found to vary with sediment depth and generally correlate with carbonate concentration in the sediment. Using Fourier transform infrared spectroscopy (FTIR), we determined that the pollen extracts were not contaminated by either carbonate or charcoal. However, contamination by algal spores could not be ruled out, and we hypothesise that those algal spores may have assimilated aged dissolved inorganic carbon during periods of higher groundwater influx, thus altering the measured radiocarbon age of the pollen extract. Macrofossil and corrected pollen radiocarbon dates were incorporated in a Bayesian age-depth model which integrated ²¹⁰Pb activities and Pu data and bomb pulse C-14 dates validated using recent historical age markers. Our results suggest that it is possible to generate a robust geochronological framework for Lake Surprise using radiocarbon dating back to at least ∼10,846 cal yr BP.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"89 ","pages":"Article 101686"},"PeriodicalIF":1.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing and dating authigenic phosphates from the sedimentary infill of Atapuerca archaeo-paleoanthropological cave sites (Spain)","authors":"I. Campaña ,&nbsp;M. Duval ,&nbsp;A. Álvaro-Gallo ,&nbsp;V. Guilarte ,&nbsp;Q. Shao ,&nbsp;A.I. Ortega ,&nbsp;L.J. Arnold ,&nbsp;M. Demuro ,&nbsp;J.M. Bermúdez de Castro ,&nbsp;E. Carbonell","doi":"10.1016/j.quageo.2025.101674","DOIUrl":"10.1016/j.quageo.2025.101674","url":null,"abstract":"<div><div>We present the results of a characterization and dating study of eight authigenic apatite samples collected from various stratigraphic units of three cave sites across the Atapuerca complex, namely Gran Dolina, Galería Complex and Sima del Elefante. Characterization analyses using X-ray diffraction, X-ray fluorescence and Electron Spin Resonance (ESR) spectroscopy have been used to determine the nature and composition of the samples: seven of them are mostly made of hydroxyapatite, while one is composed of crandallite, and all show variable amounts of contamination by calcite and/or sediment. The timing of authigenic apatite formation, which results from the weathering of the limestone in a karstic environment, has been tentatively constrained through a combination of bulk and spatially resolved analyses using ESR and U-series methods. The dating results obtained enable the identification of various formation events during the Middle and Late Pleistocene at each site, around 170–180 ka and 110–120 ka in Gran Dolina, ∼250 ka and ∼40 ka in Galería Complex, and, possibly, ∼360 ka in Sima del Elefante. Importantly, all these ages are significantly younger than the depositional age of the host sediment, thus confirming the post-depositional nature of authigenic apatite. Additionally, the absence of age consistency across sites suggests that they have all experienced independent diagenetic events, which cannot be attributed to the overall karst dynamics of the Sierra de Atapuerca, but should rather be regarded as local processes.</div><div>Beyond the dating results, this study provides an overview of the potential and current limitations of ESR and U-series methods applied to Quaternary authigenic apatite. The main complication regarding the ESR method lies in the evaluation of the internal dose rate given the high uranium concentrations measured in the samples, and the absence of a directly related alpha efficiency value for this type of material. Laser ablation U-series analyses also highlight the methodological challenges caused by significant spatial heterogeneity of the U-series data across the apatite samples, which reflects the complexity, non-uniformity and long duration of apatite formation processes around the limestone blocks.</div></div>","PeriodicalId":54516,"journal":{"name":"Quaternary Geochronology","volume":"89 ","pages":"Article 101674"},"PeriodicalIF":1.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}