Journal of South American Earth Sciences最新文献

{"title":"The Espinhaço Supergroup at the craton-orogen transition in Serra do Cipó-Brazil: Multi-statistical analyses of new and compiled detrital zircon U-Pb ages","authors":"Henrique Chaves Joncew ,&nbsp;Ginaldo Ademar da Cruz Campanha","doi":"10.1016/j.jsames.2025.105422","DOIUrl":"10.1016/j.jsames.2025.105422","url":null,"abstract":"<div><div>The Southern Espinhaço Range, located at the boundary between the São Francisco Craton and the Araçuaí Orogen, is a key geological province in western Gondwana. This study aims to improve the stratigraphic models at its southern limits, focusing on the Serra do Cipó region in Minas Gerais, Brazil. By compiling a comprehensive regional U-Pb detrital zircon age database and integrating new LA-ICPM-MS geochronological data, we established statistical patterns to determine provenance and propose stratigraphic correlations. Detrital zircon age data were analysed using kernel density estimates, Kolmogorov-Smirnov (KS) tests, and Multidimensional Scaling (MDS), revealing three statistically distinct regional affiliation groups: pre-Espinhaço, Espinhaço and Macaúbas-Jequitaí. Our findings show that pre-Bambuí siliciclastic rocks in the Serra do Cipó region strongly correlate with the Espinhaço Supergroup, particularly the Santa Rita and Galho do Miguel formations, rather than the younger Macaúbas Group or pre-Espinhaço units, allowing a for re-evaluation of previous stratigraphic models in this area. The youngest zircon grains indicate maximum deposition of Calymmian (1581 ± 35 Ma, 1579 ± 40 Ma), Statherian (1613 ± 47 Ma, 1656 ± 26 Ma), and Orosirian (1831 ± 26 Ma) ages. Detrital zircon ages suggest that sediment provenance was dominated by Neoarchaean to Paleoproterozoic cratonic sources and Mesoproterozoic magmatic events related to Espinhaço Basin rifting. Limited Calymmian-age zircon grains suggest distal sediment sources. This study refines the understanding of the Espinhaço Supergroup distribution and its role in the tectono-sedimentary history of western Gondwana, emphasizing the need for revised geological mapping at its southern limits.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"157 ","pages":"Article 105422"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical attributes and fractionation of soil organic matter in integrated and conventional agricultural production systems in the Midwest, Brazil","authors":"Paulo Guilherme da Silva Farias ,&nbsp;Camila Beatriz da Silva Souza ,&nbsp;Jolimar Schiavo ,&nbsp;Jean Sérgio Rosset ,&nbsp;Jefferson Matheus Barros Ozório ,&nbsp;Naelmo de Souza Oliveira ,&nbsp;Allan Motta Couto ,&nbsp;Michely Tomazi ,&nbsp;Júlio Cesar Salton","doi":"10.1016/j.jsames.2025.105444","DOIUrl":"10.1016/j.jsames.2025.105444","url":null,"abstract":"<div><div>Replacing conventional management with conservation practices, like crop-livestock integration and agroforestry, can boost soil organic carbon. However, humic fractions are more sensitive to management changes. This study evaluated the impact of conventional and integrated systems on soil quality, focusing on fertility and organic carbon content in the Atlantic Forest biome. Samples were collected at depths of 0–5 cm and 5–10 cm, with 5 replicates per treatment, and each replicate consisting of 5 sub-replicates collected randomly. The analysis included soil organic carbon, chemical attributes of the soil, chemical fractionation, stocks of carbon in chemical fractions of soil organic matter, and variations in carbon stocks for each chemical fraction. The treatments evaluated were Agroforestry in the pasture phase; Agroforestry in the crops phase; Crop-livestock integration with pasture; Crop-livestock integration with crops; Cultivated Forest; Conventional tillage system; No-tillage system; Permanent pasture, and degraded pasture. The results obtained were analyzed for normality and homogeneity of the data using the Shapiro-Wilk and Bartlett tests, respectively. Subsequently, the data was subjected to analysis of variance using the F test, and the mean values were compared with each other using the Scott-Knott test, both at 95% confidence level in a completely randomized design. Lower pH values were found in the degraded pasture, reaching 3.8. The conventional tillage and no-tillage systems had higher phosphorus levels than the other evaluated systems. Agroforestry systems showed statistical differences based on the crops grown between the rows. The highest soil organic carbon contents at 0–5 cm depth were found in pasture and crop-livestock integration areas. There was a 28.7% increase in organic carbon in the agroforest with pasture compared to that with crops. The pasture phase of the agroforestry system exhibited positive variations in labile carbon fractions compared to the crop phase. Both crop-livestock integration and permanent pasture systems significantly improved the quality, content, and stock of the organic soil fraction, showing higher quality indexes than the other systems.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"157 ","pages":"Article 105444"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 tide influenced braided delta in a flexural rift margin, the Mesoproterozic Lenheiro Sequence, São João del Rei basin, southern São Francisco Craton, Brazil","authors":"F. Nepomuceno ,&nbsp;L.G. Arienti ,&nbsp;A. Ribeiro ,&nbsp;R.A.J. Trouw ,&nbsp;G.L.C. Pires ,&nbsp;T.F. Martins","doi":"10.1016/j.jsames.2025.105446","DOIUrl":"10.1016/j.jsames.2025.105446","url":null,"abstract":"<div><div>The Mesoproterozoic Tiradentes Formation incorporates three shallow marine sequences followed by a deltaic to fluvial sequence, the Lenheiro Sequence. Facies analysis, grain size, bed thickness and stacking patterns, along with paleoflow data reveal that the deltaic section of the Lenheiro Sequence includes seven facies associations distributed in two intervals. The lower interval is a ca. 20 m thick succession consisting of pelite and minor sandstone that comprises the facies association FA1. This facies association is interpreted as distal shoreface-offshore deposit in a retrogradational stacking pattern. The upper interval includes at least 160 m of pelite, sandstone, pebbly sandstone and minor conglomerate with a coarsening and thickening upward stacking pattern. Six facies associations (FA2 to FA7) were recognized: prodelta, distal and proximal delta front, distributary channels of the lower and upper delta plain, and abandoned braid-channel in the upper delta plain. Facies analysis allows interpretion of the succession as a tide influenced braid delta. Tide influence is weak in the distal delta front, increases in the upper delta front, decreases in the lower delta plain, and does not affect the upper delta plain. Paleoflow data indicate progradation towards south. Northward directed paleoflow records the flood tide that reworks deposits of the delta front. The distal shoreface-offshore facies association (FA1) of the Lenheiro Sequence covers abruptly and conformably the lagoon-tidal flat facies association of the underlying shallow marine sequence. The gap between facies associations records a rapid creation of accommodation space related to rift tectonics. The sharp boundary between the two sequences is a flooding surface that in turn is overlaid by a thin transgressive system tract (FA1) formed in response to the sudden generation of accommodation. The upper interval, interpreted as a tide influenced braided delta system (Lenheiro Delta), was developed as a highstand system tract in a period of relative tectonic quiescence. The data reveal that the studied interval is a syn-rift sequence located in a flexural margin of a Mesoproterozoic rift.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105446"},"PeriodicalIF":1.7,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 screening approach for selecting fossils for molecular analysis","authors":"Damián A. Ibarra ,&nbsp;Luciano Brambilla ,&nbsp;Pablo Straccia ,&nbsp;Rubén D. Scian ,&nbsp;Lucas R. Brun","doi":"10.1016/j.jsames.2025.105454","DOIUrl":"10.1016/j.jsames.2025.105454","url":null,"abstract":"<div><div>This study investigates the presence of preserved biological remains in fossils, which could be particularly critical for future studies aimed at understanding the evolutionary history of extinct organisms. We focused on osteoderms from specimens of glipotodonts <em>Panochthus tuberculatus</em> and <em>Glyptodon reticulatus</em> from the Late Pleistocene of Argentina. Our approach involved sectioning the osteoderms and staining them with Coomassie Blue, a dye with high affinity for proteins. Additional staining techniques included Hematoxylin and eosin (H&amp;E) and Masson's Trichrome Staining on histological sections of the same specimens. Sudan IV staining was also performed to verify the presence of lipids. These methods rapidly detected proteins and lipids and mapped their spatial distribution within the specimens, enabling the selection of samples for further molecular analyses. The findings highlight the potential of these methods to advance evolutionary research and improve our understanding of relationships among extinct species.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105454"},"PeriodicalIF":1.7,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143551623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Soil Water Index of distributed tank model in a small basin with field data","authors":"Sofia Melo Vasconcellos ,&nbsp;Masato Kobiyama ,&nbsp;Aline de Almeida Mota","doi":"10.1016/j.jsames.2025.105416","DOIUrl":"10.1016/j.jsames.2025.105416","url":null,"abstract":"<div><div>The objective of the present study was to determine the spatial behaviour of the Soil Water Index (SWI) by applying a distributed version of the Tank Model (D-Tank Model) to the Araponga river basin (5.26 ha) in southern Brazil and to verify its reliability through the comparison to soil moisture estimated with the measured water-tension values and the water retention curve. The study area has a monitoring system for precipitation, discharge (5- min interval), and soil-water tension (10-min interval). The simulation results showed that the D-Tank Model has a reliable performance. The correlation between SWI and HAND was reasonable (r = 0.6) meanwhile that between SWI and the Topographic Wetness Index was high (r = 0.88). The comparison between the spatially distributed values of the SWI and soil moisture confirmed the high potential of the SWI derived from the D-Tank Model to be applied for predictions related to hydrological and environmental sciences. Keywords: D-Tank Model, Soil Water Index, Topographical Wetness Index, HAND, Soil Moisture.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"157 ","pages":"Article 105416"},"PeriodicalIF":1.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to ‘Long-term stability of sediment routing on an active continental margin: Insights from detrital zircon U-Pb ages and measured stratigraphy of Carboniferous to Miocene strata, Sierra de Narváez, NW Argentina’ [J. S. Am. Earth Sci. Volume 146, 15 October 2024, 105097]","authors":"Alexander Tye ,&nbsp;Lindsay Schoenbohm","doi":"10.1016/j.jsames.2025.105443","DOIUrl":"10.1016/j.jsames.2025.105443","url":null,"abstract":"","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105443"},"PeriodicalIF":1.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Potential and effective recharge of the Federal District shallow aquifers, Brazilian savanna region - coupled analysis of GLDAS-2, Water Table Fluctuation (WTF) and rainfall pattern","authors":"André Walczuk ,&nbsp;José Eloi Guimarães Campos ,&nbsp;Lucas Santos Batista Teles","doi":"10.1016/j.jsames.2025.105426","DOIUrl":"10.1016/j.jsames.2025.105426","url":null,"abstract":"<div><div>Aquifer recharge is a key parameter for water management. Rainfall pattern shifts combined with external factors such as vadose zone properties and evapotranspiration determine groundwater fluctuation. Different combinations of these variables within aquifer time response might cause a disequilibrium in water budget, threatening both surface and groundwater availability. An important approach to understanding groundwater behavior is the evaluation of potential and effective recharge considering multiple methodologies. This study provides an analysis of the porous aquifer of the Federal District, Brazil. The area is relevant for national and international water production, as it hosts the headwaters of three hydrographic regions: Amazonas, Tocantins-Araguaia, and Paraná/Paraguay. Potential recharge estimations and delineation of deficit periods were compiled from the National Institute of Meteorology (INMET) climatic network and have been found to be a suitable database to support rainfall distribution analysis. Effective recharge was estimated based on the water table fluctuation - WTF method applied to GLDAS-2/GRACE groundwater storage model (GWS) and water level time series of five monitoring wells. According to the satellite data, 22–40% of the corresponding hydrological year rainfall is converted into saturated zone recharge. Direct observations estimations are 22–48%. Spearman's correlation coefficients for GWS and WL are up to 0.90, so that modeled time series are reliable for trend analysis. A coupled analysis of climatic and water table data has shown that groundwater position is well described by moving average rainfall. Ideal windows were found to be between 150 and 270 days and dependent on groundwater depth, with the latter being the most representative. The study of Federal District porous aquifer for management purposes could consider a minimum of 2-year rainfall time series. Maintenance of total volume but atypical or unevenly distribution along this window has the potential to alter hydraulic head by the end of the dry season and the subsequent water table ascension period. Future work at the Cerrado Biome can consider the methods herein presented to corroborate research findings and expand the variety of geomorphological and pedological locations evaluated.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105426"},"PeriodicalIF":1.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal dynamics of suspended sediment transport in two regulated rivers in Chile","authors":"Luisa Villablanca ,&nbsp;Gemma Piqué ,&nbsp;Andrés Iroumé ,&nbsp;Bruno Mazzorana ,&nbsp;Ramon J. Batalla","doi":"10.1016/j.jsames.2025.105445","DOIUrl":"10.1016/j.jsames.2025.105445","url":null,"abstract":"<div><div>Dams alter the hydrosedimentary regime of rivers, not only modifying the longitudinal profile of the river and thus its energy gradient, but also trapping a significant portion of sediment load. Consequently, the transport of suspended and bedload sediments downstream is generally reduced. Chile exhibits diverse climatic conditions, ranging from the arid north to the humid south, with twenty-six large reservoirs. This study focuses on characterising suspended sediment transport at different temporal scales in two regulated rivers located in different climatic regions in Chile: the Loa River in the arid zone and the Biobío River in the humid zone. Additionally, sediment transport was studied in two unregulated rivers as benchmarks for natural regimes: the Salado River, a tributary of the Loa River, and the Diguillín River basin, adjacent to the Biobío River. Daily flow records and daily suspended sediment concentrations were obtained from monitoring stations located upstream and downstream of the reservoirs. Hydrological and sediment transport alterations were assessed using indicators at various temporal scales and in relation to flood magnitude and frequency. The results showed a highly scattered relationship between discharge and suspended sediment concentrations in both rivers. Contrary to expectations, the mean suspended sediment concentrations and loads were higher downstream in the Loa River, and similar upstream and downstream in the Biobío River, altogether being the consequence of the remarkable role of various large tributaries in supplying fine sediments between the reservoirs and the downstream monitoring stations. Cumulative suspended sediment frequency curves revealed that sediment transport was more irregular upstream, i.e., linked to the catchment dynamics of erosion fine sediment production, than downstream of the dams, evidencing the role of reservoirs at changing the temporal patterns of suspended sediment fluxes. Overall, reservoir regulation in the Loa and Biobío rivers did not appear to drastically alter their hydrology or sediment transport, though it did generate more constant trends of suspended sediment load downstream.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105445"},"PeriodicalIF":1.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 komatiite-associated Boa Vista Ni-Cu sulfide deposit, Crixás greenstone belt, Central Brazil: Insights into komatiite flow facies and exploration","authors":"Tiago Felipe Arruda Maia ,&nbsp;César F. Ferreira-Filho ,&nbsp;Saulo Batista de Oliveira","doi":"10.1016/j.jsames.2025.105436","DOIUrl":"10.1016/j.jsames.2025.105436","url":null,"abstract":"<div><div>The Boa Vista Ni-Cu deposit is an uncommon example of Neoarchean mineralization associated with aluminum-depleted komatiite (ADK). New data for the Boa Vista deposit, including geological and petrographic descriptions, as well as geochemical and isotopic results for komatiites and sulfide ore, are integrated into this study to improve the understanding of the processes associated with its origin. Although the deposit and host rocks were affected by tectonism and greenschist to amphibolite facies metamorphism, primary magmatic textures and compositions are variably preserved throughout the greenstone belt. Our results show that the Boa Vista deposit is hosted by an undifferentiated olivine cumulate channelized/conduit flow facies unit overlying flows of basalts and basaltic komatiites interlayered with sulfide-bearing graphite schist. The Boa Vista deposit is a Type I (basal/contact) of the komatiite-associated Ni-Cu-(PGE) deposit that was variably disrupted along shear zones. The main orebody consists predominantly of matrix ore breccia consisting of pentlandite, pyrrhotite, and minor chalcopyrite and has high Zn contents. Lithogeochemistry, AFC model, ore geochemistry, and sulfur isotopic data support crustal contamination of the komatiitic magma by graphite schist. Strongly positive δ³⁴S isotopic values for the Ni-Cu ore, ranging from +16 to +19, are modeled as resulting from contamination of the komatiitic magma with host graphite schist that contains sulfides with δ³⁴S values ranging from +30 to +34. The relatively low grades of the ores are attributable to relatively low metal tenors, consistent with a magma: sulfide ratio (R factor) calculated between 300 and 400. High Ni-MgO-Zn content can be a geochemical exploration criteria guide to finding new targets for komatiite-associated Ni-Cu-(PGE) sulfide deposits in central Brazil.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105436"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstructing late Early–Middle Jurassic environments, ecosystems and climate based on palynological and sedimentological data of the Los Molles Formation, Neuquén Basin, northwestern Patagonia, Argentina","authors":"Verónica R. Iturain ,&nbsp;Daniela E. Olivera ,&nbsp;Marcelo A. Martínez ,&nbsp;Germán Otharán ,&nbsp;Carlos Zavala","doi":"10.1016/j.jsames.2025.105425","DOIUrl":"10.1016/j.jsames.2025.105425","url":null,"abstract":"<div><div>The Los Molles Formation (Early–Middle Jurassic) in the Picún Leufú Sub-basin, Neuquén Basin, Argentina, is a clastic unit accumulated in a marine-delta system. Its deposits are rich in organic matter, and provide a detailed record for palaeoenvironmental reconstruction. The present contribution integrates sedimentological and palynological data from the Painemilla section (0–100 m interval) to infer palaeoenvironmental, palaeoecological, and palaeoclimatic conditions. The palaeoenvironment evolved from a hyperpycnal littoral delta during wetter periods to a marine littoral delta system during drier ones. The five identified palynofacies-types show a high terrestrial input due to the predominance of phytoclasts. PT-1, 2 and 5 are associated with light hyperpycnites, while PT-3 and 4 characterise offshore/prodelta deposits. Sporomorph assemblages dominated by Hirmeriellaceae and Araucariaceae are consistent with a seasonally dry (winterwet) biome. The highest values of Araucariaceae show a good correlation with the parasequences, representing the maximum water input into the basin. The <em>Callialasporites</em> complex record suggests an age no older than late Toarcian. A Sporomorph Ecogroup (SEG) analysis is applied for the first time in the Los Molles Formation. Principal Components Analysis points to variations in palaeoecology and the taphonomic component in the record (water/wind-transport taxa). This analysis reveals an active participation of the Coastal (Hirmeriellaceae), Lowland (Araucariaceae and Umkomasiaceae) and Riverside (Caytoniaceae) SEGs throughout the entire section, showing an increase in the Upland SEG supply towards the upper part of the section. This study highlights the role of light hyperpycnal flows in the sedimentary and palynological records, providing new insights into Jurassic palaeoenvironmental and ecological dynamics in the Neuquén Basin.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105425"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}