Palaeogeography, Palaeoclimatology, Palaeoecology最新文献

{"title":"Decadal to centennial scale hydroclimate oscillations on the western Loess Plateau during the past 1400 years","authors":"Jin Zhang ,&nbsp;Huiru Tang ,&nbsp;Haiwei Zhang ,&nbsp;Ashish Sinha ,&nbsp;Le Ma ,&nbsp;Jingjie Zang ,&nbsp;Yanzhen Li ,&nbsp;Liangcheng Tan","doi":"10.1016/j.palaeo.2025.113235","DOIUrl":"10.1016/j.palaeo.2025.113235","url":null,"abstract":"<div><div>Climate change exerts a profound influence on human activities, geopolitical reorganization, and ecosystem evolution across the western Loess Plateau (WLP). Here, we present a reconstruction of decadal to centennial hydroclimate variability on the WLP over the past ∼1400 years using speleothem record from Yanwu Cave with precise chronology. Based on speleothem stable isotopes (δ¹⁸O and δ¹³C) and trace elements (Sr/Ca, Mg/Ca, and Ba/Ca) analyses, we found that the stable isotopes are affected by kinetic fractionation effects and reflect a more complex climate signal, while the PC1 component of trace elements demonstrates coherent variations with regional hydroclimate records and is thus interpreted as a robust indicator of hydroclimate variability. Our reconstruction reveals that the hydroclimate variability and agricultural activity jointly dominated the vegetation evolution on the WLP. The warm-wet climate and enhanced human activities during the Medieval Climate Anomaly (MCA) may have led to reduced vegetation cover, whereas the agricultural abandonment during the early stage of the Little Ice Age (LIA) marked a transition to a cold-dry climate that led to vegetation recovery. Furthermore, severe droughts evident in both historical and proxy records likely triggered geopolitical conflicts through subsistence crises. This ecological fragility amplified societal vulnerability to hydroclimate extremes via crop failure and forced migration. Our record further demonstrates a decreased hydroclimate variability during the MCA in contrast to progressively amplified variability throughout the LIA on the decadal to multidecadal timescales, synchronizing with the increase in flood/drought frequency as documented in historical literature.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113235"},"PeriodicalIF":2.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933586","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":"Enhanced terrestrial biogenic silica flux to platform cherts in marine–continental transition zones: Evidence from the Carboniferous succession of the eastern Qaidam Basin","authors":"Hui Shi ,&nbsp;Jiaqi Wang ,&nbsp;Shuai Wang ,&nbsp;Licheng Ma ,&nbsp;Junjie Hu","doi":"10.1016/j.palaeo.2025.113239","DOIUrl":"10.1016/j.palaeo.2025.113239","url":null,"abstract":"<div><div>The Carboniferous Period witnessed a pivotal transformation in global silicon cycling, characterized by the expansion of silica-accumulating vascular plants and the proliferation of marine silicifiers. However, the role of terrestrial biogenic silica in shaping platform chert formation within marine–continental transition zones remains poorly constrained. This study investigates elemental geochemistry with δ³⁰Si–δ¹⁸O isotope analyses of Carboniferous cherts and carbonate host rocks from the eastern Qaidam Basin to elucidate their formation mechanisms and silica sources. Our results reveal that bedded and nodular cherts were primarily derived from terrestrial biogenic silica (phytoliths), as evidenced by δ¹⁸O values ranging from 21.39 ‰–25.74 ‰, overlapping with phytolith signatures and δ³⁰Si compositions (−1.44 ‰ to 0.19 ‰) distinct from those of hydrothermal or weathering-derived silica. Reconstructed seawater temperatures 8.82–12.86 °C and highly negative δ¹⁸O_sw values of −12.0 ‰ indicate meltwater influx from late Paleozoic ice age glaciers accompanied by the dissolution of phytoliths. High-frequency glacio-eustatic fluctuations regulated terrestrial-marine silicon transfer: glacial regressions exposed basin margins, fostering silica-rich forest ecosystems, whereas interglacial transgressions inundated these reservoirs, releasing dissolved silica that precipitated as authigenic chert within carbonate platforms. These findings establish terrestrial biogenic silica as a major silicon source for Paleozoic platform cherts, revising conventional models and highlighting coupled land-ocean silicon cycling in icehouse climates.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113239"},"PeriodicalIF":2.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988846","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":"Impact of astronomical forcing on sea-level changes and peat-swamp development in the Late Paleozoic of North China","authors":"Xuchao Li ,&nbsp;Zengxue Li ,&nbsp;Dongdong Wang ,&nbsp;Xiangchun Chang ,&nbsp;Ying Li ,&nbsp;Xue Zheng ,&nbsp;Kai Feng ,&nbsp;Honggang Zhao","doi":"10.1016/j.palaeo.2025.113232","DOIUrl":"10.1016/j.palaeo.2025.113232","url":null,"abstract":"<div><div>The Late Paleozoic Ice Age represents a critical phase of coal accumulation in the North China Basin. Coal was primarily deposited in marine-terrestrial transitional environments, where coal seams display distinct cyclicity closely associated with cyclic marine transgressions. Astronomical cycles are believed to play a crucial role in the evolution of climate and environmental changes during the Late Paleozoic Ice Age. To explore the impact of astronomical cycles on sea-level changes and peat swamp development, and to clarify the relationship between astronomically forced transgressions and the termination of peat swamp development, a time-series and cyclostratigraphic analysis were conducted on the Taiyuan Formation gamma ray (GR) data from well H-2 in Juye, Shandong. A floating astronomical time scale of ∼4.55 Myr for the Taiyuan Formation is constructed by astronomical tuning of GR data to the robust ∼405 kyr eccentricity cycle. Sea-level changes of the Taiyuan Formations are recovered based on the sedimentary noise model. Cyclostratigraphic analysis indicates that the high-frequency, cyclic deposition of limestone transgressive layers and coal seams was impacted by astronomical forcing. During periods of high orbital eccentricity with low precession, the Northern Hemisphere summer solstice at perihelion, resulting in warm and humid climatic conditions, enhanced precipitation, and promoting vegetation growth and peat swamp development. In contrast, high precession aligned the Southern Hemisphere summer solstice with perihelion, creating a warm summer orbit that maximized insolation and temperatures, thereby accelerating the deglaciation and collapse of Gondwana and triggering sea-level rise. Following the accumulation of glacial melt from multiple high-precession phases, rising sea-levels eventually surpassed the strait heights, leading to seawater intrusion, which submerged the peat swamps and terminated their development. The peat was preserved and subsequently formed coal seams. An ideal model was established to illustrate how astronomical forcing influences sea-level changes and the development and termination of peat swamps.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113232"},"PeriodicalIF":2.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144920020","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":"Western Pacific subtropical high regulated the spatiotemporal pattern of East Asian summer monsoon precipitation during the Holocene","authors":"Linkai Wang ,&nbsp;Junhuai Yang ,&nbsp;Fuyuan Gao ,&nbsp;Haoyu Wang ,&nbsp;Canyi Zhang ,&nbsp;Wenxi Qu ,&nbsp;Jianye Li ,&nbsp;Jinmeng Tang ,&nbsp;Xin Liu ,&nbsp;Yan Liu ,&nbsp;Lai Zhao ,&nbsp;Shuyuan Wang ,&nbsp;Youjun Wang ,&nbsp;Fei Wang ,&nbsp;Dunsheng Xia","doi":"10.1016/j.palaeo.2025.113252","DOIUrl":"10.1016/j.palaeo.2025.113252","url":null,"abstract":"<div><div>The precipitation delivered by the East Asian summer monsoon (EASM) has significantly influenced the ecological environment, climate, and economy of China. However, the mechanisms responsible for the spatiotemporal pattern of EASM precipitation remain unclear. We present a new Holocene loess-paleosol record from the Hexi Corridor on the EASM margin. Environmental magnetic parameters (χ_lf, χ_fd, χ_ARM/SIRM, and χ_fd/HIRM) indicate that precipitation was low during 14–8 ka and then increased to a maximum during 4–2 ka. Integrated with published records, our results reveal a distinct geographical gradient in the timing of the Holocene precipitation maximum: an early Holocene peak in eastern Inner Mongolia, a mid-Holocene peak in the central and eastern Chinese Loess Plateau (CLP), and a late Holocene peak in the western CLP and central Hexi Corridor. In addition to these zonal differences, we also observed a longitudinal difference in the timing of the Holocene precipitation peak, which occurred later in the southern region than in the northern region. Combined with existing paleoclimate and climate simulation results we propose that this spatial difference in the timing of the Holocene precipitation peak reflects the movement of the EASM rainfall belt related to the westward extension and northward shift of the western Pacific subtropical high. Overall, our findings provide evidence for the location of the westernmost boundary of EASM influence and offer a unified explanation for regional differences in EASM precipitation and its timing.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113252"},"PeriodicalIF":2.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917918","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":"Clastic record from Northern Tethyan Himalaya: Implication for the initial India-Asian collision in the western Yarlung-Zangpo suture zone, South Tibet","authors":"Xu-dong Guo ,&nbsp;Lin Ding ,&nbsp;Fu-long Cai ,&nbsp;Gui-zhen Guo ,&nbsp;Xiao-yan Xu ,&nbsp;Peng Han ,&nbsp;Chang-jun Gu ,&nbsp;Mei-yu Liu ,&nbsp;Xiang-li Ding ,&nbsp;Xu Liu ,&nbsp;Xin-lei Li ,&nbsp;Deng Zeng ,&nbsp;Ya-hui Yue ,&nbsp;Qiu-yun Guan","doi":"10.1016/j.palaeo.2025.113230","DOIUrl":"10.1016/j.palaeo.2025.113230","url":null,"abstract":"<div><div>The suturing process between the Indian and Asian continents in the western part of the Yarlung-Zangpo Suture Zone (YZSZ) remains unclear due to the challenging environment and the complex geological background. The bilateral material of two continents provides robust evidence for constraining the timing of the continental collision. In this study, we conducted field mapping, geochronology and provenance analyses on sandstones from the Weimei, Rilang and Denggang formations (Upper Jurassic to Eocene) within a same section in the Zhongba area. The Weimei and Rilang formations exhibit typical characteristics of Tethyan Himalayan provenance, recording the evolution of the northern margin of the Indian continent during Late Jurassic - Cretaceous. The Paleocene - Eocene Denggang formation displays a provenance distinct from the Tethyan Himalayan strata, closely aligning with the Asian deposits in the YZSZ. In the Tethyan Himalaya area, the appearance of Asian debris in the Denggang formation indicates that the collision between India and Eurasia had occurred. The maximum depositional ages of the sandstones from the Denggang formation constrain the collision between the Indian and Asian continents in the western YZSZ to no later than 56 Ma - 54 Ma.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113230"},"PeriodicalIF":2.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005050","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":"Lower Triassic conodont succession and carbon isotope profile from Zaluch, Salt Range, Pakistan","authors":"Chen Han ,&nbsp;Martyn L. Golding ,&nbsp;Laishi Zhao ,&nbsp;Shunling Wu ,&nbsp;He Zhao ,&nbsp;Zhengyi Lyu ,&nbsp;Zhong-Qiang Chen ,&nbsp;Irfan U. Jan ,&nbsp;Abdullah Khan","doi":"10.1016/j.palaeo.2025.113229","DOIUrl":"10.1016/j.palaeo.2025.113229","url":null,"abstract":"<div><div>The Salt Range in northern Pakistan is a key reference area for studying Lower Triassic biostratigraphy and chemostratigraphy, particularly with respect to conodonts and carbon isotopes. However, our current understanding of the conodonts from this region relies mainly on studies conducted in the previous century, the results of which require revision in light of recent taxonomic advancements. This paper presents an updated conodont taxonomy and biostratigraphy for the Zaluch section of the Salt Range. Twelve conodont zones are recognized, in ascending order: the <em>Hindeodus parvus</em>, <em>Isarcicella lobata</em>, <em>Is. isarcica</em>, <em>Neoclarkina krystyni</em>, <em>Sweetospathodus kummeli</em>, <em>Neospathodus dieneri-Ns. cristagalli</em>, <em>Novispathodus waageni eowaageni</em>, <em>Ns. posterolongatus</em>, <em>Nv. shani</em>, <em>Nv. pingdingshanensis</em>, <em>Triassospathodus homeri</em>, and <em>Tr. sosioensis</em> zones. These conodont zones, integrated with a high-resolution organic carbon isotope record, enable robust correlations between the Zaluch section and other well-studied Lower Triassic sections worldwide. The Permian-Triassic boundary is tentatively placed at the base of the Mianwali Formation, marked by the lowest occurrence (LO) of <em>Hindeodus parvus</em>. The Induan-Olenekian boundary, identified based on the LO of <em>Novispathodus waageni eowaageni</em>, is positioned in the middle part of the Ceratite Marls, 11.45 m above the base of the Mianwali Formation and 5 m below the P2 peak of carbon isotopic excursion of the Early Triassic. The Smithian-Spathian boundary, marked by the LO of <em>Nv. pingdingshanensis</em>, is placed at the base of the Bivalve Beds, 34.75 m above the base of the Mianwali Formation, and is associated with a sharp positive carbon isotope excursion. Additionally, two new conodont species, <em>Neospathodus prolixus</em> and <em>Ns. diminutus</em>, are described.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113229"},"PeriodicalIF":2.7,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921953","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":"Vegetation dynamics and carbon isotope responses to the early eocene hyperthermals","authors":"Peizong Lü ,&nbsp;Zuoling Chen ,&nbsp;Yongli Lu ,&nbsp;Shiling Yang ,&nbsp;Zihua Tang ,&nbsp;Zhongli Ding","doi":"10.1016/j.palaeo.2025.113238","DOIUrl":"10.1016/j.palaeo.2025.113238","url":null,"abstract":"<div><div>Early Eocene hyperthermal events, including the Paleocene-Eocene Thermal Maximum (PETM) and subsequent events (ETM2/H1, H2, and I1), provide critical insights into vegetation and carbon cycle responses to extreme warming during the Early Eocene. Here, we present multiproxy biomarker records and compound-specific δ¹³C data from the Fushun Basin in Northeast China, systematically reconstructing the vegetation dynamics and carbon flux changes during these hyperthermals. We focused on gymnosperm-derived diterpenoids and angiosperm-derived triterpenoids as tracers of floral response. During the PETM, gymnosperms experienced a transient surge in vegetation carbon flux, in contrast to angiosperms, which exhibited a persistent decline across all hyperthermal phases. This challenges the conventional paradigm of gymnosperm vulnerability to warming. Concurrently, Climate change has induced complex alterations in vegetation composition. Compound-specific δ¹³C analysis revealed a significant negative carbon isotope excursion (CIE) in diterpenoids during the PETM, comparable to that of total organic carbon (δ¹³C_TOC), suggesting that climate intensity, rather than vegetation shifts, drove isotopic fractionation. These findings highlight the differential responses of gymnosperms and angiosperms to hyperthermals, with gymnosperms dominating carbon flux during the PETM. Our study emphasizes the role of the magnitude of climate change in modulating vegetation carbon fluxes and isotopic fractionation, highlighting the need to consider plant physiological adaptations under extreme climatic conditions to understand carbon cycle dynamics.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113238"},"PeriodicalIF":2.7,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933584","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":"Normalization of fossil plant megafossil databases for diversity and palaeobiogeography analyses by filtering taxonomic duplication: Principles, methods, examples, and recommendations","authors":"Zhen Xu ,&nbsp;Emma Bateson ,&nbsp;Christopher J. Cleal ,&nbsp;Reece Hutton ,&nbsp;Jianxin Yu ,&nbsp;Shi-Jun Wang ,&nbsp;Andrew H. Knoll ,&nbsp;Benjamin J.W. Mills ,&nbsp;Jason Hilton","doi":"10.1016/j.palaeo.2025.113236","DOIUrl":"10.1016/j.palaeo.2025.113236","url":null,"abstract":"<div><div>Fossil plants are key to many palaeobiogeographic and deep time diversity studies, but correctly interpreting them can be fraught with problems due to fragmentation in the fossil record. A typical vascular plant comprises 10–12 separate organs depending on its systematic affinity, but complete individuals are exceptionally rare. Fragmentation can result from multiple processes including ontogeny during the plant's life-cycle, or from post-mortem taphonomic processes in fluvial systems. In traditional approaches where raw data is amassed directly in the field, from existing physical collections or electronic databases, duplication is inevitable in that different organs of the same plant species may be inadvertently counted independently, skewing results. Here we outline normalization methods for filtering the palaeobotanical data to remove taxonomic duplications, with examples provided from different types of preservation. We use two case studies to highlight the impact of normalization by analysing raw (unfiltered) versus normalized (filtered) data. The first case study evaluates plant data from the late Permian and Triassic compression/impression floras of South China, focussing on species richness/diversity assessments through the Permian-Triassic mass extinction and its recovery. In this case study, normalization reduced the number of taxa but revealed more detailed evolutionary patterns including the magnitude of floristic turnover, previously obscured by the fragmental preservation typical of plant fossils and nomenclature. The second case study evaluates Carboniferous to Permian anatomically preserved coal-ball floras from Europe, North America and China, focussing on palaeobiogeography and floral provinciality. Normalization reduced the number of coal-ball assemblages when surveyed at both genus and species level but revealed differences in relationships and floristic endemism. We conclude that normalized results should be considered alongside raw data, as they show important and complementary information which can greatly aid in overall interpretation.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113236"},"PeriodicalIF":2.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144912324","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":"Vertical zonation or allogenic succession? Sclerobionts on a coral patch-reef from the Lower Cretaceous Agrio Formation, Neuquén Basin, west-central Argentina","authors":"L. Luci,&nbsp;R.M. Garberoglio,&nbsp;D.G. Lazo,&nbsp;R.M. Palma","doi":"10.1016/j.palaeo.2025.113228","DOIUrl":"10.1016/j.palaeo.2025.113228","url":null,"abstract":"<div><div>Reefs are hotspots of diversity, modifying their surroundings and fostering numerous biotic interactions: in the fossil record, they preserve valuable paleoecological and paleoenvironmental information. Lower Cretaceous reefs are understudied; this paper analyzes the sclerobiont fauna of a Hauterivian patch-reef from the Neuquén Basin (Argentina) to interpret its life history and paleoenvironmental significance. Massive and ramose forms of paleoautoecologically homogeneous genera form this reef; corals bore zooxanthellae and presented features indicative of a tolerance for high-sedimentary input. Sclerobionts were analyzed separately for ramose and massive corals. In addition, the upper and lower surfaces of massive corales were also logged separately. The sclerobiont fauna comprised mainly thecideide brachiopods, oysters, serpulids, cyclostome bryozoans and calcareous sponges. In addition, in ramose corals only, microbial crusts are also recorded and encrusted by sclerobionts. Massive corals presented lower diversity indices as compared to ramose ones. In both coral morphotypes, bioclaustrated sclerobionts were registered: in particular, serpulids established mutualistic relationships with the corals. Massive corals' undersides hosted a much more abundant, sciaphyllous sclerobiont fauna. This patch reef dwelled in a mid-ramp setting under relatively high sedimentation rates; massive corals were buried more quickly than ramose forms. The microbialites settled only on ramose corals after the patch reef began to dwindle; massive ones were already buried, but ramose ones remained in life position. The arrival of microbialites indicates lowered sedimentation rates, likely due to nutrient enrichment. Thus, the pattern of sclerobiont distribution observed in these corals reflects not a vertical zonation of coeval sclerobionts, but rather an allogenic succession that evidences the progressive burial of the patch-reef. At Early Cretaceous mid-latitude settings, corals were adapted to suboptimal conditions, such as a relatively high sedimentation, sustaining a moderately diverse and dynamic sclerobiont fauna composed mostly of heterotrophic organisms.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113228"},"PeriodicalIF":2.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921729","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":"Molasse basin subsidence and paleodrainage evolution in the India-Asia collision zone: Insights from the Upper Oligocene-Lower Miocene Dazhuka Formation, Southeastern Tibet","authors":"Zhen Wei ,&nbsp;Minjia Sun ,&nbsp;Xianghui Li ,&nbsp;Jie Wan ,&nbsp;Yihong Jing ,&nbsp;Xiaolong Fan ,&nbsp;Jingyu Wang","doi":"10.1016/j.palaeo.2025.113231","DOIUrl":"10.1016/j.palaeo.2025.113231","url":null,"abstract":"<div><div>The subsidence mechanisms of the inner molasse basins, specifically the Dazhuka Formation within the Yarlung Zangbo suture zone, remain a subject of debate, and the paleo-drainage evolution recorded in these strata has been insufficiently examined. In this study, we conduct a comprehensive analysis of the sedimentary characteristics, provenance, and uplift and exhumation history of the Dazhuka Formation in southeastern Tibet—a historically underexplored region—to elucidate the subsidence mechanisms of the inner molasse basin and the evolutionary processes of the paleo-Yarlung Zangbo River. Our findings indicate that deposition of the Dazhuka Formation in the Jiacha-Langxian region likely began in the late Oligocene, characterized primarily by proximal alluvial fan deposits with paleocurrents directed southward and detritus derived exclusively from the underlying Gangdese magmatic rocks to the north. Detrital apatite fission track (AFT) dating in the Remudang area yields a central age of ∼15 Ma, suggesting that uplift and exhumation occurred during this period. By integrating low-temperature thermochronological data, depositional age constraints, and provenance analysis from our study and regional data along the suture zone, we reveal that: (1) the depositional ages of the Dazhuka Formation become progressively younger from the syntaxis to Luobusha in an east-west direction, while exhumation ages remain nearly synchronous, aligning with regional slab breakoff and underthrusting processes and corroborating that subsidence was caused by slab rollback; (2) no axial paleodrainage system developed during the late Oligocene to early Miocene in the eastern part of the suture zone. However, by the middle Miocene, the paleo-Yarlung Zangbo River caused intense incision there, indicating that the evolution of the axial river system likely differed between areas east and west of Luobusha.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"678 ","pages":"Article 113231"},"PeriodicalIF":2.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917917","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}