Palaeogeography, Palaeoclimatology, Palaeoecology最新文献

{"title":"Cenozoic evolution of the Indus Basin: Multi-proxy insights from sedimentary successions in western Ladakh, India","authors":"Bibhukalyan Acharya,&nbsp;J. Amal Dev,&nbsp;Sohan Kumar,&nbsp;Tomson J. Kalukalam,&nbsp;Poonam Verma,&nbsp;Prasanta Sanyal,&nbsp;Pradeep Srivastava","doi":"10.1016/j.palaeo.2026.114194","DOIUrl":"10.1016/j.palaeo.2026.114194","url":null,"abstract":"<div><div>Sedimentary successions deposited within the forearc basin of the Indus-Yarlung Suture Zone contain an archive of pre-, <em>syn</em>-, and post-collisional tectono-sedimentary events. By synthesising data from previously studied sections and a new dataset from a section along the Chiktan Nala, this paper attempts to reconstruct the Cenozoic landscape evolution of the underexplored western part of the Indus Basin, considering palaeogeography and regional tectonic dynamics. Our results from a multi-proxy investigation demonstrate that the stratigraphy along the Chiktan Nala represents a <em>syn</em>-collisional continental clastic succession of the Indus Basin, with no evidence of marine ingression within the studied stratigraphy, contrary to previous suggestions. Sediment provenance evolved from the Kohistan-Ladakh Arc to the Dras Arc over time within a fluvio-lacustrine to alluvial fan depositional system. Continental sedimentation in this part of the basin began by 44 Ma. It continued at least until 18 Ma, after which the Zanskar back-thrust system likely drove basin inversion and southward tilting. Basin drainage was reorganised to an axial configuration through the initiation of a major west-flowing river. We add to the evidence that this river was a plausible precursor to the Indus River. These findings refine the tectono-sedimentary framework of the Indus Basin in western Ladakh, providing new constraints on the timing of post-collisional continental sedimentation and provenance evolution, with broader implications for reconstructing basin-scale drainage reorganisation and Cenozoic palaeoclimatic evolution in the Himalayas.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"702 ","pages":"Article 114194"},"PeriodicalIF":2.9,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148998520","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":"Fortunian small skeletal fossils and carbon isotope stratigraphy of the Bayangol Formation type section at Bayan Gol, southwestern Mongolia","authors":"Gundsambuu Altanshagai,&nbsp;Marissa J. Betts,&nbsp;Guoxiang Li,&nbsp;Bing Pan,&nbsp;Luoyang Li,&nbsp;Iban Goñi,&nbsp;Stephanie A. Richter Stretton,&nbsp;Dorj Dorjnamjaa,&nbsp;Batkhuyag Enkhbaatar,&nbsp;Peiyao Wang,&nbsp;Yanlong Chen,&nbsp;Timothy P. Topper","doi":"10.1016/j.palaeo.2026.114195","DOIUrl":"10.1016/j.palaeo.2026.114195","url":null,"abstract":"<div><div>The Zavkhan Basin of southwestern Mongolia preserves one of the most complete mixed carbonate–siliciclastic archives of the Ediacaran–Cambrian transition globally, yet the precise chronostratigraphy of the Bayangol Formation at its type locality of Bayan Gol has remained contentious. Conflicting age interpretations, ranging from entirely Nemakit–Daldynian (Fortunian in the global scheme) to partially Tommotian (approximately Stage 2), have persisted largely as a consequence of composite section construction across tectonically complex, faulted terrain and the decoupling of biostratigraphic and chemostratigraphic datasets. Here we present a high–resolution, integrated small shelly fossil (SSF) biostratigraphy and δ¹³C chemostratigraphy derived from a single, continuous stratigraphic section measured through 359 m (true thickness) of the Bayangol Formation. Two successive SSF biozones are recognised: the <em>Anabarites trisulcatus–Protohertzina anabarica</em> Assemblage Zone in the uppermost Zuun–Arts and basal Bayangol formations, directly above the Basal Cambrian Carbon Isotope Excursion (BACE), and the <em>Purella antiqua</em> Zone, defined by the lowest occurrence of <em>Purella antiqua</em> and positioned between positive carbon isotope excursions 3p and 4p. A markedly abundant and diverse micromollusc assemblage in the uppermost member BG4, including <em>Ilsanella compressa</em>, <em>Barskovia mongolica</em>, and <em>Nomgoliella sinistrivolubilis</em>, is correlated with the Fortunian Stage in the global scheme (upper Nemakit–Daldynian of the Siberian Platform and broadly with Zone II of the Yangtze Platform of the South China Block). The absence of <em>Watsonella crosbyi</em> and positive excursion 5p (ZHUCE) from the measured succession demonstrates that members BG2–BG4 are entirely Fortunian in age, and that the Fortunian–Stage 2 boundary lies either within the overlying member BG5 or the Salaanygol Formation. These results resolve a long–standing chronostratigraphic controversy and provide a robust, multi–proxy framework for correlating the Mongolian record with global Terreneuvian reference successions.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"702 ","pages":"Article 114195"},"PeriodicalIF":2.9,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148998912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Shifting patterns in tropical lake phytoplankton communities coinciding with anthropogenic nutrient and pollutant trends","authors":"Dongna Yan ,&nbsp;Yongming Han ,&nbsp;Patrick Rioual ,&nbsp;Jianghu Lan ,&nbsp;Sifan Zan ,&nbsp;Yalan Tang ,&nbsp;Huijia Zhang ,&nbsp;Meiling Guo ,&nbsp;Eric Capo","doi":"10.1016/j.palaeo.2026.113623","DOIUrl":"10.1016/j.palaeo.2026.113623","url":null,"abstract":"<div><div>Natural- and human-induced environmental changes lead to structure shifts in phytoplankton communities, impacting the resilience, functioning, and ecosystem services of lakes. Given the scarcity of long-term monitoring data, particularly in the tropical region, our understanding of phytoplankton communities (cyanobacteria and eukaryotic micro-algae) and their triggering factors remains limited over decadal scales. We determined whether shifts in phytoplankton community within Huguangyan Maar Lake, a tropical lake, are linked to climate warming and assessed whether the observed changes resemble those documented in temperate or arctic regions. We applied 23S rRNA gene metabarcoding to 43 sediment samples covering the past ∼140 years, and explored how the phytoplankton community respond to multiple environmental stresses. Phytoplankton diversity exhibited a marked increase beginning in the 1940s, followed by a distinct decline in the 1980s. Notably, a significant shift in community composition emerged toward the late 1980s, characterized by a rise in the relative abundance of diatoms (Aulacoseiraceae) and a concurrent decrease in rhodophytes (Bangiaceae) and cyanobacteria (Synechococcaceae). This pattern contrasted sharply with trends observed in other lakes, where cyanobacteria have maintained dominance in recent decades.Through integrated application of Mantel tests and random forest multivariate modeling, nutrient loading emerged as the predominant driver of community restructuring outweighing climatic factors. Concurrently, anthropogenic combustion signatures, such as polycyclic aromatic hydrocarbons, demonstrated significant covariance with phytoplankton assemblage reconstructing. This study highlights the dual impact of anthropogenic nutrients input and pollutants on phytoplankton communities in tropical lakes and provides important implication for future pollution and nutrient control.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113623"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191878","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-system geochronometer constraints on thermo-tectonic evolution of the Qiangtang Terrane, central Tibetan Plateau: Comment","authors":"Xiao-Long Song ,&nbsp;Ru-Ye Tian ,&nbsp;Kang-Yu Li","doi":"10.1016/j.palaeo.2026.113582","DOIUrl":"10.1016/j.palaeo.2026.113582","url":null,"abstract":"<div><div>The elevation of the Tibetan Plateau constitutes a revolutionary event in Earth's history, but the chronologic evolution and mechanistic drivers of plateau formation persist as subjects of intense contention. Recently, Lei et al. (2026) proposed that the Tibetan Plateau underwent pulse-like growth and that the rapid elevation of the Qiangtang block during the 120–90 Ma due to the Lhasa–Qiangtang continental collision. However, the extensive literature records of Cretaceous marine deposition over the Qiangtang block does not support its rapid elevation during 120–90 Ma and studies reveal that the subduction of the Meso- and Neo-Tethys oceanic lithospheres could have played a critical role in the initial elevation of the Qiangtang and Lhasa blocks prior to the Cenozoic Indo–Asian collision. An insufficient incorporation of regional sedimentary, structural and tectonic data under over-reliance on limited thermochronological data has seriously undermined the soundness and reliability of Lei et al.'s work.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113582"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192509","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":"Provenance transition between the Xiamaling and Changlongshan formations in the North China Craton and its paleogeographic implications","authors":"Zhongyu Meng ,&nbsp;Bangfang Ren ,&nbsp;Jian Tian ,&nbsp;Wenchao Niu ,&nbsp;Weitong Li ,&nbsp;Lixin Sun","doi":"10.1016/j.palaeo.2026.113635","DOIUrl":"10.1016/j.palaeo.2026.113635","url":null,"abstract":"<div><div>The Meso-Neoproterozoic strata in the North China Craton provide significant insights into the major Precambrian geological events and the paleogeographic reconstruction. This study investigates the stratigraphy, sedimentology, and provenance analysis of the Xiamaling and Changlongshan formations in the Yanliao Rift Basin. We reveal significant provenance variations and their correlations with regional tectonic events, thereby reconstructing the paleogeographic evolution. The Xiamaling Formation is dominated by shelfal shales interbedded with siltstones and sandstones, whereas the Changlongshan Formation consists of coastal quartzose sandstones. The two formations are in unconformable contact, marked by an abrupt change in sedimentary facies that reflects a change in the regional tectonic setting. Sandstones of the Xiamaling Formation contain abundant felsic volcanic rock fragments, and detrital zircon U<img>Pb age spectra display bimodal peaks in the Paleoproterozoic (∼1.8 Ga) and late Paleoproterozoic–early Mesoproterozoic (∼1.6 Ga), with ε_Hf(t) values ranging from −8.6 to +2.5, and − 8.7 to +8.1, respectively. By contrast, Sandstones from the Changlongshan Formation are quartz-dominated and show a single peak of late Neoarchean–early Paleoproterozoic (∼2.5 Ga), and yielded ε_Hf(t) values between − 3.4 and + 5.5. The ∼2.5 Ga zircon ages correspond to continental crustal growth and initial cratonisation. The ∼1.8 Ga peak reflects the collisional amalgamation of the eastern and western blocks of the NCC, forming a unified crystalline basement. The ∼1.6 Ga peak represents magmatic activity in an extensional setting. The paleogeographic evolution of the Yanliao Rift Basin can be reconstructed into three stages: Intracontinental extension (∼1.40–1.32 Ga), tectonic uplift (∼1.32–1.00 Ga), and widespread marine transgression (∼1.00–? Ga).</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113635"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192508","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 Hirnantian-Rhuddanian succession in East Central United States: New implications for latest Ordovician to early Silurian sea level","authors":"Cole F. Farnam ,&nbsp;Carlton E. Brett ,&nbsp;Lincoln Shoemaker ,&nbsp;Jisuo Jin ,&nbsp;Robert J. Elias ,&nbsp;Christopher B.T. Waid","doi":"10.1016/j.palaeo.2026.113548","DOIUrl":"10.1016/j.palaeo.2026.113548","url":null,"abstract":"<div><div>A detailed understanding of the Late Ordovician to early Silurian glaciations and Hirnantian mass extinctions requires high resolution pattern and timing of sea level and climatic events. The record is particularly poorly known in the eastern USA, which was previously assumed to lack Hirnantian strata. Synthesis of new and previously reported biostratigraphic evidence and carbon isotope chemostratigraphy indicates that thin but widespread, fossiliferous upper Hirnantian strata are preserved in southern Ohio and southeastern Indiana. Elevated values of δ¹³C_carb, within and just beneath strata of the <em>Ozarkodina hassi</em> Zone, in siltstones and carbonates of the lower Whippoorwill Formation (new, herein) of the Cincinnati Arch in Ohio and Indiana, indicate the signature of the upper part of the Hirnantian isotopic carbon excursion (HICE). The presence of conodonts of the <em>O. hassi</em> Zone and brachiopods, corals, and a large dalmanitid trilobite belonging to the globally recognized Edgewood-Cathay fauna strongly supports a latest Hirnantian age for the Whippoorwill Formation. Sequence stratigraphy of the Whippoorwill Formation and the immediately overlying interval allowed for recognition of two thin (possibly 4th order) sequences in the Ohio and Indiana region (Hirnantian-2A (H2A), Centerville Member, and Hirnantian-2B (H2B), Belfast Member). The older Hirnantian (H1) sequence is absent in the greater Cincinnati region and probably truncated beneath the composite H2 or Cherokee Unconformity. Locally, the H2A and H2B sequences are truncated or completely removed beneath the higher Rhuddanian S1A erosion surface (base Brassfield Formation). In turn, the highly irregular lower Aeronian S2B erosion surface (base Oldham) can also locally cut deeply through lower Silurian, Hirnantian, and even upper Katian strata. Correlation of these sequences and their bounding unconformities across eastern North America reveals widespread sequences probably controlled by glacioeustasy during the latest Hirnantian and Rhuddanian.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113548"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122670","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":"A 2000-year paleofire record from the Tashkurgan Wetland (Pamir Plateau, China): Implications for the impact of Silk Road human activities","authors":"Xiaoxiao Liu ,&nbsp;Yun Zhang ,&nbsp;Yanhong Zhou ,&nbsp;Zhaochen Kong","doi":"10.1016/j.palaeo.2026.113612","DOIUrl":"10.1016/j.palaeo.2026.113612","url":null,"abstract":"<div><div>Reconstructing the paleofire history along the Silk Road enhances our understanding of the complex interplay between natural processes and human activities, and provides a critical perspective on the long-term ecological and environmental evolution of the region. This study conducts a multi-proxy analysis of a sedimentary profile from the Zoroastrian wetland (STCN) on the Pamir Plateau, China, integrating fossil pollen, magnetic susceptibility, and microscopic charcoal records to examine paleofire patterns and anthropogenic influence over the past two millennia. Results indicate that paleofire activity was relatively low from approximately 1900 to 1300 years ago. Beginning around 1300 cal a BP, however, a rise in synanthropic plant pollen occurred alongside increased concentrations of macro-charcoal particles (&gt;125 μm) and higher magnetic susceptibility. These shifts correlated with the development of the Western Regions during the Tang Dynasty and the spread of Zoroastrian fire-worship practices. Between 670 and 540 cal aBP (corresponding to the Yuan-Ming period), secondary peaks in macro-charcoal concentration and magnetic susceptibility, alongside a rise in synanthropic plant pollen and low large Poaceae (&gt;45 μm) content, coincided with agricultural and military activities under the Chagatai Khanate. Since 140 cal a BP, the concentrations of macro-charcoal and the abundance of large Poaceae and synanthropic plant pollen have reached their highest recorded levels, likely driven by population growth, intensified agricultural development, and recurrent warfare. Significant correlations among large Poaceae, <em>Taraxacum</em> pollen, and macro-charcoal particles suggest fire regimes linked to the burning of agricultural crops or anthropogenic weeds, further underscoring the role of human activity. Multi-proxy evidences indicate that human activities along the Silk Road, such as agricultural practices, ritual fire use, and military conflicts, were important factors driving paleofire activity in the region. Particularly during the Yuan–Ming period and the Qing Dynasty, the intensity of human activities showed a synchronous increase with fire frequency, macro-charcoal particle concentrations, pollen content of anthropogenic plants, and magnetic susceptibility values. This research reveals the complex interactions within the human–fire–vegetation system along the Silk Road, providing important insights into the long-term responses of arid ecosystems to human activities.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113612"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192503","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":"Constraints of paleoenvironment on selenium enrichment of the Ediacaran-Cambrian transition period Lujiaping Group in the North Daba Mountains, China","authors":"Sujiao Yang ,&nbsp;Shixi Zhang ,&nbsp;Yingjie Luo ,&nbsp;Jiulong Cheng ,&nbsp;Kunli Luo","doi":"10.1016/j.palaeo.2026.113637","DOIUrl":"10.1016/j.palaeo.2026.113637","url":null,"abstract":"<div><div>The Lujiaping Group (LG), a diachronous unit spanning the Ediacaran-Cambrian transition period in the North Daba Mountains, China, exhibits notable selenium (Se) enrichment. However, the distribution patterns and enrichment mechanisms remain poorly understood. In this study, we analyzed the elemental content and lithology of 61 rock samples from the LG named section in Ziyang County. The Se concentrations ranged from 0 ∼ 147.86 μg/g, with an average of 16.31 μg/g. The LG was subdivided into 5 Formations (Doushantuo Formation (DST), Dengying Formation (DY), Huoshiwan Formation (HSW), Baihe Formation (BH), Shanpingshang Formation (SPS)) from bottom to top, all showing Se enrichment with average enrichment factor (EF=content/upper continental crust (UCC))&gt;2. The BH of the Terreneuvian of the Cambrian showed the highest Se enrichment (mean EF=663.56), while the upper part of the SPS of the Series 2 of the Cambrian showed the lowest Se enrichment (mean EF=3.45). Geochemical and petrographic characteristics suggest that hydrothermal influence was most pronounced in the DST to the lower part of the HSW, while the upper part of the HSW to the SPS received more input from terrestrial sources, and the upper part of the HSW to the lower part of the SPS received more from organism sources. Additionally, paleoenvironmental and paleoclimatic factors such as alternating anoxic-euxinic and suboxic conditions, high primary productivity, intermittent upwelling, and a warm, moist climate may have further promoted Se enrichment.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113637"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192504","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":"Speciation patterns of elements Cl and Br in marine sediments and their significant as salinity proxies","authors":"Shiwen Zheng ,&nbsp;Dejiang Fan ,&nbsp;Xueshi Sun ,&nbsp;Lisha Hu ,&nbsp;Yulong Xue ,&nbsp;Judong Mao ,&nbsp;Peng Cheng ,&nbsp;Xiaolin Ren ,&nbsp;Jian Wang","doi":"10.1016/j.palaeo.2026.113621","DOIUrl":"10.1016/j.palaeo.2026.113621","url":null,"abstract":"<div><div>Salinity is a fundamental hydrochemical parameter of marine environments, yet the reconstruction of paleosalinity remains one of the most challenging issues in paleoceanographic research field. To investigate the potential of conservative elements (Cl, Br) as proxies for seawater salinity variations, this study systematically analyzed the surface sediments collected across the Eastern China marginal seas, where pronounced salinity gradients exist. Through comprehensive examination of Cl and Br speciation mechanisms in sediments, we established quantitative relationships between these halogens and seawater salinity. The results indicated that dissolved Cl and Br dominate their total sedimentary inventories, accounting for 90.27% and 86.14% respectively, while non-dissolved fractions consistently represent &lt;15% of total content. The non-dissolved Cl appears primarily associated with terrigenous silicate minerals, showing stable concentration patterns, whereas non-dissolved Br predominantly occurs in organic matter with clear source-dependent correlations. Significantly, in sediments of the Eastern China marginal seas, dissolved Cl demonstrates an exponential correlation with bottom water salinity. Particularly in brackich water regimes (salinity &lt;30.4 psu), both dissolved Cl and dissolved Br exhibit strong linear relationships with bottom water salinity, enabling quantitative paleosalinity reconstruction in estuarine environments. This research establishes a novel methodological framework for paleosalinity investigations and provides crucial constraints for interpreting paleo-marine environments with sedimentary geochemistry proxies.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113621"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192501","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":"Eastern Brazil hydroclimate weakening linked to stronger AMOC during MIS 16–13","authors":"B. Gomes ,&nbsp;I.M. Venancio ,&nbsp;J.M. Ballalai ,&nbsp;T.S. Figueiredo ,&nbsp;A.G. Almeida ,&nbsp;A.L.S. Albuquerque","doi":"10.1016/j.palaeo.2026.113622","DOIUrl":"10.1016/j.palaeo.2026.113622","url":null,"abstract":"<div><div>Several paleoclimate studies focus on the impacts of changes in Atlantic Meridional Overturning Circulation (AMOC) on the dynamics of the South American Monsoon System (SAMS) on millennial timescales; however, they lack interpretations on longer timescales throughout the Quaternary. Here, we present a sediment core covering the last 1 million years collected in the tropical region of the eastern Brazilian margin near the São Francisco River mouth. We used the ln(Si/Al) as hydroclimate proxy, interpreting as changes in the SAMS activity, and also δ¹³C of benthic foraminifera to track associated changes on AMOC deep-water circulation. We observed substantial changes between 700 and 400 ka, marked by the weakening of the SAMS simultaneously with increasing long-term trend of δ¹³C, suggesting a coupled ocean-atmosphere changes across this period. We infer that the observed increase in ventilation is a response to a stronger AMOC, which leads to a global northward migration of the Intertropical Convergence Zone (ITCZ), resulting in a decrease in SAMS intensity. Thus, our data offer insights into long-term coupled responses between the oceanic and atmospheric systems in the tropical realm during the Quaternary.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"688 ","pages":"Article 113622"},"PeriodicalIF":2.7,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192505","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}