Quaternary Science Reviews最新文献

{"title":"A substantial meltwater event on the northeastern Tibetan Plateau during the middle to late Holocene transition","authors":"Zheng Wang ,&nbsp;Fan Zhang ,&nbsp;Xiangzhong Li ,&nbsp;Meng Xing ,&nbsp;Yunning Cao ,&nbsp;Huanye Wang ,&nbsp;Jing Hu ,&nbsp;Hongxuan Lu ,&nbsp;Jibao Dong ,&nbsp;Hu Liu ,&nbsp;Zhonghui Liu ,&nbsp;Weiguo Liu","doi":"10.1016/j.quascirev.2024.108996","DOIUrl":"10.1016/j.quascirev.2024.108996","url":null,"abstract":"<div><div>Global warming has accelerated the degradation of permafrost and glaciers on the Tibetan Plateau, resulting in a substantial release of meltwater that is affecting the regional ecosystem. Despite the significant environmental effects of meltwater, there is a lack of comprehensive studies on the historical changes in meltwater. The key is to obtain reliable quantitative records of meltwater changes. Here, we present Holocene δDwax records from a loess and a peatland on the northeastern Tibetan Plateau, documenting the hydrogen isotopic composition of the regional summer precipitation and surface water affected by meltwater respectively. The two records together reveal substantially increased meltwater during the middle to late Holocene transition, lasting for approximately 1500 years. The meltwater event coincides with a series of exceptional warmth during 5-3 ka across the mid-latitude inland Asia, suggesting that the regional warming was the primary driver of the increased meltwater. This meltwater event had a considerable influence on regional ecology, leading to dramatic fluctuations in algal and bacterial populations and biomass. In addition, this meltwater event may have occurred over a larger area of glaciers and permafrost, where the water isotope records during 5 ka and 3 ka differ from low-latitude regions. This meltwater event, as a crucial aspect of the climatic changes during the middle to late Holocene transition in inland Asia, its driving mechanism and environmental impacts warrant further investigation.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108996"},"PeriodicalIF":3.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418832","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 paleoenvironmental and paleoclimatic variability in a high mountain lake in Sierra Nevada (Spain): Insights from diatom analysis","authors":"Joana Llodrà-Llabrés ,&nbsp;Gonzalo Jiménez-Moreno ,&nbsp;Antonio García-Alix ,&nbsp;R. Scott Anderson ,&nbsp;Francisco J. Jiménez-Espejo ,&nbsp;Charo López-Blanco ,&nbsp;Marta Rodrigo-Gámiz ,&nbsp;Carmen Pérez-Martínez","doi":"10.1016/j.quascirev.2024.108984","DOIUrl":"10.1016/j.quascirev.2024.108984","url":null,"abstract":"<div><div>This study examines the Holocene history of Río Seco Lake (3040 m a.s.l; Sierra Nevada, Southern Spain) by analysing diatom remains and other paleoenvironmental data. The aim is to understand the impact of long-term environmental and climatic variability on the aquatic ecosystem over the past 21,000 years. Our results suggest that shifts in diatom assemblages were mainly climate-driven in terms of temperature and water availability. The absence of diatom remains during the Late Pleistocene indicated low temperatures and prolonged lake snow cover. Five distinct periods were identified during the Holocene. The high abundance of epiphytic and bog-inhabiting taxa and tychoplanktonic <em>Tabellaria flocculosa</em> in the period 11,000–6700 cal yr BP were indicative of a humid climate. The onset of the tychoplanktonic <em>Aulacoseira alpigena</em> between 6700 and 5100 cal yr BP indicated a drop in temperature. These changes intensified during the period 5100–3300 cal yr BP, when the most significant changes in diatom assemblages took place with the dominance of <em>A. alpigena</em> and an abrupt increase in the abundance of the epiphytic <em>Fragilaria radians</em>. During the subsequent period (3300–1500 cal yr BP), the significant declines in <em>A. alpigena</em> and in epiphytic taxa were indicative of increased aridity and higher alkalinity values due to increased aridity and Saharan dust input during this period. The last period (1500–256 cal yr BP) was characterized by a rise in the abundance of <em>Staurosirella pinnata</em>, indicative of warmer temperatures and higher alkalinity values coincident with a marked increase in proxies of temperature and aridity. The increase in aridity and temperature during the last period, which has led to changes in diatom assemblages, is a matter of great concern in an ecosystem that is particularly susceptible to global warming.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108984"},"PeriodicalIF":3.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cosmogenic surface exposure (10Be) dating of raised beaches in Marguerite bay, Antarctic Peninsula: Implications for relative sea-level history","authors":"Cengiz Yıldırım ,&nbsp;Attila Çiner ,&nbsp;Mehmet Akif Sarıkaya ,&nbsp;Alan Hidy","doi":"10.1016/j.quascirev.2024.108995","DOIUrl":"10.1016/j.quascirev.2024.108995","url":null,"abstract":"<div><div>Understanding the dynamics of ice mass loss in polar regions is crucial for deciphering climate change and Glacio Isostatic Adjustment patterns. This study focuses on Marguerite Bay, located in the south-central Antarctic Peninsula. We dated raised beaches to investigate relative sea-level changes using the cosmogenic surface exposure (¹⁰Be) method. Previous studies have provided valuable insights into the region's glacial history, but limitations in dating techniques and age estimates necessitate further investigation. By analysing raised shingle beaches in Gaul Cove of Horseshoe Island and the southern coast of Calmette Bay, this research aims to contribute relative sea-level change history for these areas. In Horseshoe Island's Gaul Cove, raised beaches clustered on prominent steps reveal a 15 m relative sea-level change over the last 3.31 ka. Differently, Calmette Bay exhibits a 36 m relative sea-level fall over the last 7.29 ka. These findings indicate significant and differential glacial-isostatic adjustments in both regions during the middle and late Holocene. Additionally, our data reveal accelerated sea-level fall periods corresponding to Holocene deglaciation and glacial advance events, indicating the shorelines' relative sea-level change sensitivity to climate change.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108995"},"PeriodicalIF":3.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418831","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":"Disentangling seasonal and annual precipitation signals in the tropics over the Holocene: Insights from δD, alkanes and GDGTs","authors":"Petter L. Hällberg ,&nbsp;Rienk Smittenberg ,&nbsp;Malin E. Kylander ,&nbsp;Joan Villanueva ,&nbsp;Nina Davtian ,&nbsp;Anggi Hapsari ,&nbsp;Jenny K. Sjöström ,&nbsp;Josefine Axelsson ,&nbsp;Guillermo Jarne-Bueno ,&nbsp;Kweku Yamoah ,&nbsp;Hamdi Rifai ,&nbsp;Frederik Schenk","doi":"10.1016/j.quascirev.2024.108948","DOIUrl":"10.1016/j.quascirev.2024.108948","url":null,"abstract":"<div><div>Rainfall seasonality in the tropics has a substantial impact on both ecosystems and human livelihoods. Yet, reconstructions of past rainfall variability have so far generally been unable to differentiate between annual and seasonal precipitation changes. Past variations in seasonality are therefore largely unknown. Here, we disentangle hydrogen isotopic (δD) signals from terrestrial leaf waxes and algae in an 8000-year peat core from Sumatra, which reflect annual versus wet season rainfall signals, respectively. We validate these results using lipid biomarkers by reconstructing vegetation dynamics via <em>n</em>-alkane distributions and peatland hydrological conditions using glycerol dialkyl glycerol tetraethers (GDGTs), as well as biomass burning using levoglucosan concentrations in the core. Finally, we compare our proxy results to a transient climate model simulation (MPI-ESM1.2) to identify the mechanism for seasonality changes. We find that algal δD indicates stronger Indonesian-Australian Summer Monsoon (IASM) precipitation in the Mid-Holocene, between 8 and 4.2 cal ka BP. A period of alternating flooding, droughts and wildfires is reconstructed between 6 and 4.2 cal ka BP, implicating very strong monsoonal precipitation and drying out and burning during a longer and intensified dry season. We attribute this strong rainfall seasonality in the Mid-Holocene mainly to orbitally forced insolation seasonality and a strengthened IASM, consistent with the modeling results. In terms of annual rainfall, terrestrial plant δD, vegetation composition and GDGTs all indicate wetter conditions peaking between 3 and 4.5 cal ka BP, preceded by drier conditions, followed by drastic and rapid drying in the late Holocene from around 2.8 cal ka BP. Our multiproxy annual precipitation reconstruction thereby indicates the wettest overall conditions approximately 1500–2000 years later than a nearby speleothem δ¹⁸O record, which instead follows the seasonally biased algal δD in our record. We, therefore, hypothesize that speleothem reconstructions over the Holocene in parts of the tropics with low but significant seasonality may carry a stronger seasonal component than previously suggested. The data presented here contribute with new insights on how isotopic rainfall proxies in the tropics can be interpreted. Our findings resolve the seasonal versus annual components of Holocene rainfall variability in the Indo-Pacific Warm Pool region, highlighting the importance of considering seasonality in rainfall reconstructions.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108948"},"PeriodicalIF":3.2,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Terminal glacial overdeepenings: Patterns of erosion, infilling and new constraints on the glaciation history of Northern Switzerland","authors":"Marius W. Buechi ,&nbsp;Angela Landgraf ,&nbsp;Herfried Madritsch ,&nbsp;Daniela Mueller ,&nbsp;Maria Knipping ,&nbsp;Franziska Nyffenegger ,&nbsp;Frank Preusser ,&nbsp;Sebastian Schaller ,&nbsp;Michael Schnellmann ,&nbsp;Gaudenz Deplazes","doi":"10.1016/j.quascirev.2024.108970","DOIUrl":"10.1016/j.quascirev.2024.108970","url":null,"abstract":"<div><div>Glacially overdeepened basins are a common landform of subglacial erosion. However, the controlling erosional–depositional processes and their age remain poorly understood on a global scale. Terminal overdeepenings near the former glacier margins are critical for the understanding of subglacial processes and their development over time. This study examines the geomorphology and sedimentology of buried terminal overdeepenings eroded below the Rhein Glacier and adjacent lobes in the distal northern foreland of the European Alps. The evolution of erosion and infilling in the overdeepened troughs over time is investigated using high-quality drill cores (∼1463 m of core in total) that were logged for lithofacies, petrophysical, geotechnical and compositional properties. The drill data is integrated with 2D-reflection seismics (∼41 km in total) and supplementary subsurface data. This extensive dataset reveals that the studied overdeepened basins include twelve typical facies associations (partially emplaced in characteristic sequences) and characteristic architectural elements. These categories serve as effective tools to reduce the high facies variability and facilitate easier comparison and correlation of the valley fill. Our analysis shows that the formation of terminal overdeepenings on soft sedimentary bedrock (Molasse) is the result of a combination of erosional processes. Subglacial water erosion and evacuation are the dominant processes and active during periods of glacier–bed decoupling and flushing. Direct subglacial erosion occurs during glacier–bed coupling and is documented by bedrock glacitectonites. The valley fill architecture shows that the studied overdeepenings typically undergo a multiphase evolution, with several phases of overdeepening erosion, deposition and partial re-erosion (or re-activation). The combined dataset (including geochronological data) suggests that the overdeepenings were eroded during many, if not all, extensive glaciations during the Middle–Late Pleistocene that reached the distal foreland. These are findings relevant for the large number of overdeepenings known from the Northern Alpine foreland and overdeepened features worldwide. They corroborate the importance of overdeepenings as archives for the paleoenvironmental change and landscape evolution during the Quaternary.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108970"},"PeriodicalIF":3.2,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methane emissions from proglacial lakes: A synthesis study directed toward Lake Agassiz","authors":"Laura S. Brosius ,&nbsp;Katey M. Walter Anthony ,&nbsp;Thomas V. Lowell ,&nbsp;Peter Anthony ,&nbsp;Jeffery P. Chanton ,&nbsp;Miriam C. Jones ,&nbsp;Guido Grosse ,&nbsp;Andy J. Breckenridge","doi":"10.1016/j.quascirev.2024.108975","DOIUrl":"10.1016/j.quascirev.2024.108975","url":null,"abstract":"<div><div>Large proglacial lakes could have been a significant methane source during the last deglaciation. Today, proglacial lakes are small and mostly limited in the northern hemisphere to the margins of ice sheets in Greenland, Alaska, and Canada, but much larger proglacial lakes collectively flooded millions of square kilometers in the northern hemisphere over the last deglacial period. We synthesize new and existing methane flux measurements from modern proglacial lakes in Alaska and Greenland and use these data together with reconstructed lake area and bathymetry, new paleorecords of sediment organic geochemistry, carbon accumulation, and other proxies to broadly constrain the possible deglacial methane dynamics of a single large North American proglacial lake, Lake Agassiz. While large influxes of glaciogenic material contributed to rapid organic carbon burial during initial lakes phases, limited bioavailability of this carbon is suggested by its likely subglacial origin and prior microbial processing. Water depths of &gt;20 m across 37–90% of the lake area facilitating significant oxidation of methane within the water column further limited emissions. Later phases of lake lowering and subsequent re-expansion into shallow aquatic and subaerial environments provided the most significant opportunity for methane production according to our estimates. We found that Lake Agassiz was likely a small source [0.4–2.7 Tg yr⁻¹ mean (0.1–9.9 Tg yr⁻¹ 95% CI)] of methane during the last deglaciation on par with emissions from modern wildfires. Although poor constraints of past global proglacial lake areas and morphologies currently prevent extrapolation of our results, we suggest that these systems were likely an additional source of methane during the last deglacial transition that require further study.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108975"},"PeriodicalIF":3.2,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358771","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 Holocene record of subantarctic glacier variability in Table Fjord, Cook Ice Cap, Kerguelen Islands","authors":"Léo Chassiot ,&nbsp;Emmanuel Chapron ,&nbsp;Elisabeth Michel ,&nbsp;Vincent Jomelli ,&nbsp;Vincent Favier ,&nbsp;Deborah Verfaillie ,&nbsp;Anthony Foucher ,&nbsp;Joanna Charton ,&nbsp;Martine Paterne ,&nbsp;Nathalie Van der Putten","doi":"10.1016/j.quascirev.2024.108980","DOIUrl":"10.1016/j.quascirev.2024.108980","url":null,"abstract":"<div><div>The subantarctic islands between 40 and 60°S are circum-polar landmasses influenced by the southern westerly wind (SWW) belt whose latitudinal shifts are driven by the Southern Annular Mode (SAM) over decadal timescales. In the Indian sector of the Southern Ocean, the Kerguelen Islands (49°S) form a volcanic archipelago that is home to the Cook Ice Cap (CIC). Atmospheric drying favored by a poleward migration of the SWW induced a dramatic shrinkage of the CIC over the past 50 years. Current knowledge of how this decline compares with the natural variability of the CIC is unclear and based exclusively on geomorphological records with limited temporal resolution. This paper introduces a 4 kyr marine record built from a transect of giant piston cores collected in Table Fjord, southwestern margin of the CIC. Interpretation of sedimentary and geochemical proxies is supported by statistical correlations with the CIC surface mass balance on the instrumental timescale, and by the age overlapping with dated landforms and deposits over the last two millennia. High-resolution geochronological data (¹³⁷Cs and ²¹⁰Pb inventories along with 63 AMS ¹⁴C dates) corrected from a local marine reservoir age allowed reconstructing glacier variability at a multidecadal resolution. The CIC was paced by periods of glacial advances at 3.4–2.8, 2.3–1.7, and 1.35–1.15 ka cal BP, followed by a two-stage ‘Little Ice Age’ maximum between 0.7 ka cal BP and the early 20th century. Comparison with paleoenvironmental records from the subantarctic fringe zone and the southern mid-latitudes suggests SWW-driven precipitation (wetter and windier conditions) were the main driver of centennial-scale glacier variability in the Kerguelen Islands, notably after 2.3 ka cal BP. The Kerguelen record thereby supports a zonally-synchronous, hemispheric-wide SWW pattern pacing Southern Ocean climatic variability in a SAM-like mode. The Little Ice Age maximum ice extent results from the coincidence of cold conditions caused by an equatorward shift of the Polar Front, an oceanic front bordering the Kerguelen archipelago resulting in lower sea surface temperatures, together with wetter conditions favored by strengthened SWW.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108980"},"PeriodicalIF":3.2,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358772","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":"Methane flux from Beringian coastal wetlands for the past 20,000 years","authors":"Matthias Fuchs ,&nbsp;Miriam C. Jones ,&nbsp;Evan J. Gowan ,&nbsp;Steve Frolking ,&nbsp;Katey Walter Anthony ,&nbsp;Guido Grosse ,&nbsp;Benjamin M. Jones ,&nbsp;Jonathan A. O'Donnell ,&nbsp;Laura Brosius ,&nbsp;Claire Treat","doi":"10.1016/j.quascirev.2024.108976","DOIUrl":"10.1016/j.quascirev.2024.108976","url":null,"abstract":"<div><div>Atmospheric methane (CH₄) concentrations have gone through rapid changes since the last deglaciation; however, the reasons for abrupt increases around 14,700 and 11,600 years before present (yrs BP) are not fully understood. Concurrent with deglaciation, sea-level rise gradually inundated vast areas of the low-lying Beringian shelf. This transformation of what was once a terrestrial-permafrost tundra-steppe landscape, into coastal, and subsequently, marine environments led to new sources of CH₄ from the region to the atmosphere. Here, we estimate, based on an extended geospatial analysis, the area of Beringian coastal wetlands in 1000-year intervals and their potential contribution to northern CH₄ flux (based on present day CH₄ fluxes from coastal wetland) during the past 20,000 years. At its maximum (∼14,000 yrs BP) we estimated CH₄ fluxes from Beringia coastal wetlands to be 3.5 (+4.0/-1.9) Tg CH₄ yr⁻¹. This shifts the onset of CH₄ fluxes from northern regions earlier, towards the Bølling-Allerød, preceding peak emissions from the formation of northern high latitude thermokarst lakes and wetlands. Emissions associated with the inundation of Beringian coastal wetlands better align with polar ice core reconstructions of northern hemisphere sources of atmospheric CH₄ during the last deglaciation, suggesting a connection between rising sea level, coastal wetland expansion, and enhanced CH₄ emissions.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108976"},"PeriodicalIF":3.2,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tectonic deformation and kinematics of fluvial terraces marking the northeastern margin of the Tibetan Plateau","authors":"Zijuan Dong ,&nbsp;Baotian Pan ,&nbsp;Zhenbo Hu ,&nbsp;David Bridgland ,&nbsp;Jun Wang ,&nbsp;Rob Westaway ,&nbsp;Menghao Li ,&nbsp;Qinhong Mo ,&nbsp;Xiaohua Li ,&nbsp;Xilin Cao ,&nbsp;Meiling Zhong ,&nbsp;Renzhe Pan","doi":"10.1016/j.quascirev.2024.108978","DOIUrl":"10.1016/j.quascirev.2024.108978","url":null,"abstract":"<div><div>This paper reports on a study of the geometry and kinematics of numerous active faults within the Qilian Shan-Hexi Corridor area, which has provided valuable insights into regional deformation patterns. The Jintanan Shan faults are located at the northern end of the Hexi Corridor. In the Jintanan Shan range, five gaps have been excavated by rivers originating from the Qilian Shan, and have well-preserved fluvial terrace sequences in them, with evidence for deformation. Terrace profiles measured by the Differential Global Positioning System and ‘Structure-from-Motion’ processing were used to constrain the fold deformation, and a fault-related fold model was applied to estimate mountain growth and deformation kinematics. Using the geometry of the faults, as well as optical stimulated luminescence (OSL) dating and ¹⁰Be exposure dating control for the terraces, the rates of crustal shortening, vertical uplift and fault slip show estimated ranges of 0.19–1.35 mm/a, 0.21–2.14 mm/a and 0.29–2.27 mm/a, respectively, since ∼159 ka. The geometry and kinematics of the Jintanan Shan faults enable us to estimate the deformation pattern in the northern Hexi Corridor, which indicates that this area is undergoing northeastward compression relative to the northern Tibetan Plateau (Qilian Shan). Active faults in the region are principally driven by the northeastward push of the Tibetan Plateau, with the eastward extension of the Altyn Tagh fault probably playing a coordinated role.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108978"},"PeriodicalIF":3.2,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358769","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":"10Be chronology of the Last Glacial Maximum and Termination in the Andes of central Chile: The record of the Universidad Glacier (34° S)","authors":"Hans Fernández-Navarro ,&nbsp;Juan-Luis García ,&nbsp;Samuel U. Nussbaumer ,&nbsp;Dmitry Tikhomirov ,&nbsp;Francia Pérez ,&nbsp;Isabelle Gärtner-Roer ,&nbsp;Marcus Christl ,&nbsp;Markus Egli","doi":"10.1016/j.quascirev.2024.108968","DOIUrl":"10.1016/j.quascirev.2024.108968","url":null,"abstract":"<div><div>Reconstructing mid-latitude glacier variations is a prerequisite for unveiling the interhemispheric climate linkages and atmospheric-ocean forcings that triggered those changes during the last glacial cycle. Nonetheless, the timing, magnitude, and structure of glacier fluctuations in the southern mid-latitudes remain incomplete. Here, we present a new ¹⁰Be chronology of the Universidad Glacier in the Andes of central Chile (34° S, 70° W; ∼2500 m a.s.l.) based on 21 cosmogenic-exposure ages of boulders on discrete moraine ridges defining former ice margins. Our findings include the mapping and dating of three moraines, UNI I, UNI II, and UNI III, located ∼20 km, 15 km, and 10 km down-valley from the present-day glacier front, respectively. The ¹⁰Be exposure ages of the UNI I moraine range from 135.9 ± 7.1 to 51.4 ± 2.7 ka (n = 3). The UNI II moraine gave a mean age of 18.0 ± 0.9 (n = 15) and the UNI III moraine yielded a mean age of 13.9 ± 0.8 ka (n = 3). The UNI I moraine implies the largest ice extent during a pre-Last Glacial Maximum (pre-LGM) period, including the penultimate glaciation. The UNI II is a moraine complex that represents cold and humid conditions in central Chile at the end of the LGM, which we attribute to the northward-shift of the Southern Westerly Winds (SWW). The UNI III moraine represents a return to glacial conditions interrupting the Termination, evidencing both a double-step deglacial trend observed through the southern middle and high latitudes at the end of the last ice age. The Andes at this subtropical latitude record a global signal of glacial and climate change.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"344 ","pages":"Article 108968"},"PeriodicalIF":3.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322358","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}