Quaternary Science Reviews最新文献

{"title":"Late Quaternary inundation and desiccation of Megalake Chad traced in dust records from the Equatorial Atlantic Ocean","authors":"Anya J. Crocker ,&nbsp;Christopher W. Kinsley ,&nbsp;Amy M. Jewell ,&nbsp;Paul S. Breeze ,&nbsp;Nicholas A. Drake ,&nbsp;David McGee ,&nbsp;Charles S. Bristow ,&nbsp;Katie Manning ,&nbsp;Claudia Di Biagio ,&nbsp;Paola Formenti ,&nbsp;William R.C. Burton ,&nbsp;Annie L. Murray ,&nbsp;James Barlow ,&nbsp;Matthew J. Cooper ,&nbsp;Chuang Xuan ,&nbsp;Paul A. Wilson","doi":"10.1016/j.quascirev.2025.109503","DOIUrl":"10.1016/j.quascirev.2025.109503","url":null,"abstract":"<div><div>Modern Lake Chad has shrunk in area by around 90 % since the 1960s under the twin pressures of climate change and increasing water demand. During the early to mid Holocene, the Chad basin featured a megalake with an area approximately 100 times larger than its modern remnant. In the mid/late Holocene (approximately 5000 years ago), this megalake dried out leaving behind vast deposits of readily deflated fine-grained sediments that are suggested to contribute ∼25 % of the annual total global atmospheric mineral dust load. Erosion has obliterated much of the evidence of earlier North African humid periods within the Lake Chad basin, limiting our understanding of the relationship between global/regional climatology, local hydrology and dust export. Here, we present new records of thorium-normalized flux estimates of mineral dust and its radiogenic isotope composition deposited at Ocean Drilling Program Site 662, situated downwind of Megalake Chad underneath the North African winter dust plume, in the equatorial Atlantic Ocean. Our records show that sediments of the Megalake Chad basin have a distinct neodymium isotopic signature that can be traced thousands of kilometers downwind from their source when the megalake basin was dry and dust-active, whereas the fingerprint of its input was strongly suppressed at times of high lake levels. Our results show that marine sedimentary archives can preserve uninterrupted proxy records of climate-driven hydrological change on the continents, in this case, a bellwether region of Africa that features the world's most active dust source, the Bodélé Depression.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109503"},"PeriodicalIF":3.2,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate and human forcing of montane vegetation dynamics during the past 15,600 years in the Simmental, Northern Swiss Alps","authors":"Sina C. Aregger ,&nbsp;Lieveke van Vugt ,&nbsp;Erika Gobet ,&nbsp;Petra Zahajská ,&nbsp;Ebbe H. Nielsen ,&nbsp;Adriano Boschetti ,&nbsp;Albert Hafner ,&nbsp;Christoph Schwörer ,&nbsp;Hendrik Vogel ,&nbsp;Matthias Erb ,&nbsp;Ulrich Erb ,&nbsp;Willy Tinner","doi":"10.1016/j.quascirev.2025.109470","DOIUrl":"10.1016/j.quascirev.2025.109470","url":null,"abstract":"<div><div>To assess future responses of mountain ecosystems to anthropogenic climate warming, a thorough understanding of long-term vegetation responses to past climatic and land-use changes is required. Currently, little is known about former vegetation and land-use dynamics at intermediate elevations in the Swiss Alps, which act as an important ecotone between lowland and subalpine ecosystems. Here, we present a palaeoecological reinvestigation from Chutti (941 m a.s.l.), a small mire located in the montane belt of the Simmental (Simmen valley) in the north-western Swiss Alps. Using pollen, spores, stomata, microscopic charcoal, and X-ray fluorescence (XRF), we reconstructed vegetation, fire, land-use, and environmental dynamics over the past <em>c.</em> 15,600 years. Our pollen record shows four major vegetation transitions: the first transition at <em>c.</em> 14,600 cal yr BP marked the expansion of boreal forests with <em>Juniperus</em>, <em>Betula</em>, and <em>Pinus</em>, the second at <em>c.</em> 11,500 cal yr BP the expansion of temperate continental forests composed of, e.g., <em>Ulmus</em>, <em>Tilia</em>, and <em>Acer</em>, the third at <em>c.</em> 7000 cal yr BP the prevalence of temperate oceanic forests dominated by <em>Abies alba</em>, and the fourth at <em>c.</em> 4800 cal yr BP the massive spread of boreal <em>Picea abies</em>. While the first three vegetational changes were likely controlled by climate, the latter was induced by land use. The strong landscape opening during the Bronze Age (4150-2750 cal yr BP; 2200-800 cal yr BCE) was linked to the existence of a hill-top settlement close to the site. The degree of vegetation openness during the Bronze Age, but also during subsequent epochs, is unique for a site in the Northern Swiss Alps and comparable to more central places on the Swiss Plateau. Based on our results, we argue that if sustainable farming practises are not reinforced, future climate change will result in massive vegetation reorganisations in the Northern Swiss Alps, including the re-expansion of temperate forests.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109470"},"PeriodicalIF":3.2,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing past and present. The Holocene and Marine Isotope Stage 3 microvertebrate assemblage of Ararat-1 Cave, Armenia","authors":"Dominik L. Rogall ,&nbsp;Hugues-Alexandre Blain ,&nbsp;Ioannis A.K. Oikonomou ,&nbsp;Theodoros Karampaglidis ,&nbsp;Artur Petrosyan ,&nbsp;Boris Gasparyan ,&nbsp;Ariel Malinsky-Buller","doi":"10.1016/j.quascirev.2025.109512","DOIUrl":"10.1016/j.quascirev.2025.109512","url":null,"abstract":"<div><div>The Ararat-1 Cave site, situated within the dry mountain steppe zone of Armenia at an elevation of 1,034 m, preserves a stratigraphic sequence spanning Marine Isotope Stage (MIS) 3 and the Holocene (MIS 1). The site has yielded a rich microvertebrate assemblage comprising 18 extant taxa, including rodents, insectivores, lagomorphs, amphibians, and reptiles. Middle Paleolithic deposits (52-35 kyrs, MIS 3) are characterized by taxa such as <em>Chionomys nivalis</em> (Snow Vole), <em>Ellobius</em> sp. (Mole Voles), <em>Microtus arvalis</em> (Common Vole), <em>Microtus socialis</em> (Social Vole), <em>Meriones</em> sp. (Jirds), <em>Mus</em> sp. (Mice), <em>Nothocricetulus migratorius</em> (Grey Dwarf Hamster), <em>Scarturus</em> sp. (Jerboas), <em>Crocidura</em> sp. (White-toothed Shrews), <em>Erinaceus concolor</em> (Southern White-breasted Hedgehog), <em>Ochotona</em> cf. <em>rufescens</em> (Afghan Pika), <em>Bufotes</em> gr. <em>viridis</em> (Green Toads), Agamidae indet. (Agamids), Erycinae indet. (Sand Boas), Colubridae indet. 1 and 2 (Colubrids), <em>Natrix tessellata</em> (Dice Snake), and <em>Vipera</em> gr. <em>berus</em> (Vipers). Holocene layers (SU0.1–SU1.3) exhibit a similar taxonomic composition, though lacking <em>C. nivalis</em>, <em>Ellobius</em> sp., <em>O.</em> cf. <em>rufescens</em>, as well as Erycinae indet., Colubridae indet. 1 and 2, and <em>Natrix tessellata</em>. A comprehensive taxonomic and taphonomic analysis of the small mammal and herpetofaunal assemblages was conducted, employing the Taxonomic Habitat Index Method to reconstruct local ecological conditions during MIS 3 and the Holocene. Small mammal taxa indicate the coexistence of both cold- and warm-adapted species, while herpetofaunal assemblages predominantly exhibit Eastern-Mediterranean and Turano-Mediterranean affinities, with the <em>V. berus</em> complex being a notable exception due to its European or Sibero-European distribution. Paleoenvironmental reconstruction reveals a mosaic landscape comprising open semi-arid shrublands and grasslands interspersed with forested patches, rocky terrain, and a perennial water source. This environment closely resembles the modern “mountain steppe” and “dry mountain steppe” biomes of southern Armenia. The findings from Ararat-1 Cave underscore the ecological diversity present in the Southern Caucasus during both the Pleistocene and Holocene and contribute to a deeper understanding of the region's paleoenvironments.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109512"},"PeriodicalIF":3.2,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ (splash-form) tektites from the Middle Pleistocene laterite deposits in Bose Basin, south China","authors":"Xuening Song ,&nbsp;Tianjing Zhu ,&nbsp;Jinyou Mo ,&nbsp;Christopher J. Bae ,&nbsp;Wei Wang","doi":"10.1016/j.quascirev.2025.109500","DOIUrl":"10.1016/j.quascirev.2025.109500","url":null,"abstract":"<div><div>The Australasian tektite strewn field (ATSF) is the most recent and largest confirmed tektite strewn field to date, representing a major extraterrestrial impact event (Australasian Tektite Event, AATE) around 0.8 Ma. Despite the fact that a considerable number of tektite locations have been discovered in this region, the majority lack a clear stratigraphic origin. Whether these tektites can serve as event-stratigraphic markers near the Early-Middle Pleistocene boundary has long been a topic of debate. The Bose (or Baise) Basin in Guangxi, southern China, is located at the northernmost edge of the ATSF and has perhaps received the greatest attention due to its association with the Paleolithic artifacts. In Bose, splash-form tektites are commonly preserved in the reticular mottled red clay layers of the fourth terrace (T4) of the Youjiang River, alongside Acheulean-like Paleolithic stone tools. Based on the age of these tektites, researchers have suggested that the earliest handaxe-making in eastern Asia could date back to 0.8 Ma. Most of the tektites found in Southeast Asia, the area of the ATSF with the highest rate of tektite distribution, are found in association with Neolithic or even more recent artifact deposits. For this reason, scholars have vigorously debated whether the age of the Bose tektite is representative of the actual age of the Acheulean stone tools from there. Here, we report on 155 splash-form tektites, unearthed during archaeological excavations at the Nanbanshan locality of the Damei site in the Bose Basin. Incidentally, this is the first time that such a dense layer of <em>in situ</em> tektites have been discovered in Quaternary sediments. Our study indicates that this tektite layer occurs primarily below the Brunhes/Matuyama boundary in the flood-plain sediments, showing clear stratigraphic significance. The surface morphology of these tektites, the particle-size analysis and the soil micromorphological analysis of the associated sediments together indicate that these tektites from T4 of the Bose Basin are from clear <em>in situ</em> provenance. Our analyses reveal a range of morphological types of tektites in the northernmost margin of the ATSF. This study further strengthens the view that the production of the Acheulean-like stone artifacts, likely made by <em>Homo erectus</em> in Southeast Asia including southern China, occurred simultaneously with the most recent tektite falling event.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109500"},"PeriodicalIF":3.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144562834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 1700-year peatland-based hydroclimate record from the Hengduan Mountains in the southeastern Tibetan Plateau reveals changing dynamics of the summer monsoon interface","authors":"Yingfan Xia ,&nbsp;Zhengyu Xia ,&nbsp;Zicheng Yu","doi":"10.1016/j.quascirev.2025.109501","DOIUrl":"10.1016/j.quascirev.2025.109501","url":null,"abstract":"<div><div>The Indian summer monsoon (ISM) and the East Asian summer monsoon (EASM) affect precipitation patterns across the broad Asian continent. The southern Hengduan Mountains region in the southeastern Tibetan Plateau is located at the ISM–EASM interface, but how these two monsoon systems affect long-term regional precipitation variability remains unclear. Here, we develop a 1700-year record of centennial-scale hydroclimate variability from a rarely reported <em>Sphagnum</em>-dominated subalpine peatland in the southern Hengduan Mountains, using <em>Sphagnum</em>-specific cellulose δ¹³C and δ¹⁸O proxies that are supported by characterization of modern proxy–environment relationships.</div><div>Based on the modern variability of cellulose δ¹³C and δ¹⁸O in <em>Sphagnum</em> growth increments, we show that δ¹³C is a reliable proxy for moisture availability, following the “water film” mechanism. In contrast, δ¹⁸O is controlled by multiple mechanisms and can increase due to either higher precipitation δ¹⁸O and stronger evaporative enrichment under drier conditions or increased plant use of evaporated pool water caused by pool expansion under wetter conditions. Using the time-varying δ¹³C–δ¹⁸O correlation as a constraint, we infer from our coupled cellulose δ¹³C–δ¹⁸O records several centennial-scale moisture shifts, including wet shifts during 700–1200 CE, 1500–1800 CE, and after 1950 CE, and dry shifts during 300–700 CE, 1200–1500 CE, and 1800–1950 CE, with a generally wetter Medieval Warm Period than the Little Ice Age. The temporal pattern is consistent with previously published regional pollen-climate records but shows disparities from those lake-based terrestrial input records. Based on our novel single-stem isotope analysis, we hypothesize that the latter might be additionally affected by changes in extreme event characteristics.</div><div>We find that our new hydroclimate record shows an in-phase relationship with ISM records in the Indian subcontinent, except during 1500–1800 CE and in recent decades, during which our analysis presents evidence for an increased influence from EASM system. We attribute the transitions in large-scale hydroclimate patterns during these two periods to La Niña mean-state and anthropogenic radiative forcing, respectively, which weaken zonal wind flows over the Bay of Bengal—the key passage of the ISM. This study highlights the non-stationary relationship between hydroclimate and Asian summer monsoon dynamics at the ISM–EASM interface.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109501"},"PeriodicalIF":3.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144562835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proxy System Biases partially resolve long-standing paleoclimate data-model discrepancies in Tropical East Africa","authors":"Charlie Marshall ,&nbsp;Carrie Morrill ,&nbsp;Sylvia Dee ,&nbsp;Yueyang Jiang ,&nbsp;Sue Kim ,&nbsp;James Russell","doi":"10.1016/j.quascirev.2025.109426","DOIUrl":"10.1016/j.quascirev.2025.109426","url":null,"abstract":"<div><div>Paleoclimate data-model comparison is a vital tool for evaluating climate model performance and constraining predictions of climate change. Paleoclimate records provide an important out-of-sample target to test models in climates with different boundary conditions and improve model physics. General Circulation Models (GCMs) from the Paleoclimate Model Intercomparison Project (PMIP) underestimate temperature changes in tropical Africa during key periods in the past, calling into question model predictions of future climate change in this region. We compare a new suite of 8 temperature records from tropical African lakes derived from glycerol dialkyl glycerol tetraethers (GDGTs) to simulations of the Last Glacial Maximum (LGM, 21 kya) and mid-Holocene (MH, 6 kya) from PMIP3 and PMIP4, and find that there is significant proxy/model temperature disagreement during both periods; GCMs are over 2 °C cooler than proxies during the MH, and 2 °C warmer than proxies during the LGM. This could arise from issues with GCMs or the GDGT records. We use a proxy system model (PSM) to investigate multiple potential sources of proxy uncertainty, including non-stationarity in the relationship between air and lake temperature, seasonality, and calibration error. We find that proxy system error <em>can</em> account for significant portions of this discrepancy during the MH (up to 80%) assuming the maximum possible error for each potential source, but not during the LGM. Our findings highlight potential areas for improvement in interpretation of proxy records by explicitly modeling and quantifying uncertainty in reconstructed temperatures.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109426"},"PeriodicalIF":3.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"C3/C4 vegetation dynamics and hydroclimate variations in South China over the last two glacial-interglacial cycles","authors":"Xiaoyi Dong ,&nbsp;Huayu Lu ,&nbsp;Chenghong Liang ,&nbsp;Hongyan Zhang ,&nbsp;Michael Meadows ,&nbsp;Cheng Zhao ,&nbsp;Shuangwen Yi ,&nbsp;Yao Wang ,&nbsp;Yao Gu ,&nbsp;Fan Yang ,&nbsp;Fuzhi Lu","doi":"10.1016/j.quascirev.2025.109507","DOIUrl":"10.1016/j.quascirev.2025.109507","url":null,"abstract":"<div><div>The responses of climate and environment in the tropical-subtropical monsoon region of East Asia to both internal and external forcings remain poorly understood, largely due to the scarcity of high-resolution terrestrial records that span multiple glacial-interglacial cycles. In this study, we present an organic carbon isotope (δ¹³C_org) record from Tianyang maar lake in Guangdong Province, tropical South China, covering the past ∼250 kyr. This record reflects significant variations in the relative abundance of C₃ and C₄ biomass in the local terrestrial vegetation at orbital timescales, which we contend are primarily driven by changes in regional precipitation. Specifically, C₄ plants dominate in the drier climates of glacial periods, while C₃ plants thrive in the more humid conditions of interglacial periods. Superimposed on glacial-interglacial alternations, C₃/C₄ vegetation composition and associated precipitation exhibit high-frequency fluctuations, for which corresponding spectral analysis reveals prominent half-precession signals. This suggests a linkage between the ecosystem and hydroclimate dynamics in the study region and equatorial insolation at orbital timescales, with El Niño/Southern Oscillation (ENSO)-like variability possibly acting as a bridging mechanism. Our findings highlight the combined influence of glacial and low-latitude insolation forcings on terrestrial ecosystems and hydroclimate in tropical East Asia, thereby enhancing our understanding of the variability and forcing mechanisms of the East Asian Summer Monsoon (EASM) during the late Quaternary.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109507"},"PeriodicalIF":3.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144562836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early Pleistocene interglacial-glacial deposits in Denmark linked to the Matuyama Chron and MIS 22–21","authors":"Christian Kronborg ,&nbsp;Ole Bjørslev Nielsen ,&nbsp;Claus Beyer ,&nbsp;Erik Thomsen","doi":"10.1016/j.quascirev.2025.109502","DOIUrl":"10.1016/j.quascirev.2025.109502","url":null,"abstract":"<div><div>Middle Jutland, Denmark, holds some of the oldest Pleistocene deposits in northern Europe, both interglacial and glacial deposits are present. The interglacial deposits, recognized as the Harreskovian Interglacial, have traditionally been referred to the Cromerian Complex, but the reason for this assignment is unclear. It is, however, evident that the deposits are connected to the early expansion of the Scandinavian ice sheet onto the North European lowland. The scope of this paper is to examine and hopefully clarify some of these issues. The critical geological unit in the study is the Harreskovian Interglacial gyttja. This gyttja is overlain by two interstadial units, Ølgod I and Ølgod II, and underlain by totally 54 m of glacial deposits comprising five tills alternating with beds of meltwater sand. A closely related succession appears at Starup 45 km south of Harreskov, but here the glacial deposits below the interglacial sediments consist entirely of glacial lake clay. The glacial succession rests directly on Neogene sand. We have analysed 112 samples for palaeomagnetic polarity. The samples gave all reverse polarity except for the lowermost four samples at Starup, which showed normal polarity. Correlating our results with the Global Magnetic Polarity Time Scale (GMPTS) and the benthic Marine Isotope Stages (MIS), we assign the sedimentary successions as a whole to the reverse Matuyama Chron. The Harreskovian Interglacial and the two overlying interstadials are correlated to MIS 21, whereas the tills and meltwater sand are referred to MIS 22. The normal polarity samples at the base of the lacustrine clay at Starup are referred to the Kamikatsura normal excursion. We suggest that the tills represent the first advances of the Scandinavian Ice Sheet into Denmark. The advance probably stopped in the southern part of Jutland, as indicated by the lack of evidence for ice in Schleswig-Holstein and northern Germany.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109502"},"PeriodicalIF":3.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144535680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Pleistocene megalake system in the Yinchuan-Hetao rifting basins, upper reaches of the Yellow River","authors":"Xiaobo Liu ,&nbsp;Cheng Quan ,&nbsp;Zhonghui Liu ,&nbsp;Rongxi Li","doi":"10.1016/j.quascirev.2025.109473","DOIUrl":"10.1016/j.quascirev.2025.109473","url":null,"abstract":"<div><div>Lacustrine paleoenvironment reconstructions integrating geomorphic and sedimentary archives yield critical insights into hydrologic variability across basins. The Yinchuan Basin (YCB) and Hetao Basin (HTB), large active rifting basins along the upper reaches of the Yellow River, are connected by the Wuhai broad valley (WBV). While the HTB was once occupied by \"Megalake Hetao\" (HTML) during the period from ∼100 ka to 60–50 ka, the coeval lacustrine histories of the YCB and WBV remain unclear. This study combines field investigations, optically stimulated luminescence (OSL) dating, and grain-size distribution (GSD) analyses to reconstruct the late Pleistocene paleoenvironmental conditions in the YCB and WBV. Our results reveal that lacustrine deposits in the WBV and YCB record two distinct phases of high lake levels during Marine Isotope Stage (MIS) 5–4. Rising lake levels in the YCB, HTB, and WBV coalesced to form a unified water body, designated as Megalake Yinchuan-Hetao. The first lake rise developed between ∼100 ka and 73 ka (MIS 5), facilitated by sustained low subsidence rates of basins coupled with elevated precipitation. An ephemeral lake-level drop at ∼73 ka exhibited temporal correlation with regional paleoseismic activity, potentially triggering dam breaching and lake-level drop. The second lake rise, spanning ∼73–67 ka (MIS 4), manifested under cooler climatic conditions, characterized by elevated sediment influx and contracted accommodation space of basins associated with persistent tectonic quiescence, ultimately culminating in lake spillover and drainage of lakes. These findings enhance our understanding of the broader hydrology and the evolutionary paleogeography of the upper reaches of the Yellow River, providing a case study on the tectonic and climatic factors that influenced paleolake formation within rifting basins in modern arid settings.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"365 ","pages":"Article 109473"},"PeriodicalIF":3.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144535759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Holocene glacier-climate history of the Calluqueo glacier and Monte San Lorenzo, central Patagonia","authors":"Carly Peltier ,&nbsp;Michael R. Kaplan ,&nbsp;Rodrigo L. Soteres ,&nbsp;Juan-Carlos Aravena ,&nbsp;Esteban A. Sagredo ,&nbsp;Ally Peccia ,&nbsp;Gonzalo Amigo ,&nbsp;Roseanne Schwartz ,&nbsp;Joerg M. Schaefer","doi":"10.1016/j.quascirev.2025.109482","DOIUrl":"10.1016/j.quascirev.2025.109482","url":null,"abstract":"<div><div>We present 33 new ¹⁰Be exposure ages on boulders rooted in moraines in the Calluqueo valley in central Patagonia. The former glacier flowed westward off the Monte San Lorenzo massif and was expanded from ∼6,900 until ∼6,700 years ago; and at 5,620 ± 200, 5,140 ± 150, 4,660 ± 180, 4,100 ± 140, 3,610 ± 200, 3,120 ± 110 years ago (n=2 for these groups), and repeatedly during the last ∼600 years. Glaciers may have advanced earlier in the Holocene, but additional effort is needed to elucidate the timing. Also taking into account a record in the nearby Tranquillo Valley, we see that at Monte San Lorenzo glaciers were expanded often between ∼7 and ∼3 ka, and after ∼1.4 ka. During the middle Holocene moraines were built on average every ∼500 years. The largest expansions of the last millennium were at ∼1400–1500 CE. We also date boulders on the innermost moraine terrain to 1810 CE ± 20 and 1870 CE ± 20 years. A last phase of stability existed from ∼1800 to 1940 CE, with pronounced ongoing retreat since after 1940 CE.</div><div>The Monte San Lorenzo chronologies allow us to compare Holocene records between central and southernmost Patagonia. Throughout Patagonia, there is a similar glacier-climate history, with nested moraine sets and the largest glaciers generally in the mid-early Holocene. In most places, a marked change in glacier behavior and climate occurred around 7 ka, but some sites exhibit evidence of earlier Holocene activity. Over the last millennium, a net decrease in extent of advances occurred from ∼1400 to ∼1800 CE. However, there are some differences across Patagonia. In central Patagonia (∼44–49°S), glaciers expanded between 4 and 3 ka, while from 3 to 2 ka moraines are not preserved; the pattern appears reversed to the south (i.e. south of ∼49°S).</div><div>We hypothesize that Subantarctic or high latitude climates strongly impacted at least as far as northern Patagonia throughout the Holocene, including centennial and millennial changes in cold phases reflecting shifts in the Southern Hemisphere Westerlies and associated air masses. One exception perhaps is between 4 and 3 ka, where moraines are not observed to the south, possibly reflecting closer proximity to Antarctica where this interval may be generally warm. Regardless of secondary differences across southern South America, glacier records in central Patagonia are unlike those in the Northern Hemisphere, but similar to other records in the Southern Hemisphere. For comparison, anthropogenic climate change has caused climate, and thus glacier, behavior to be more in sync between the hemispheres, whereas longer-term Holocene records show distinct differences in histories even regionally within South America.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"366 ","pages":"Article 109482"},"PeriodicalIF":3.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144535679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}