Journal of South American Earth Sciences最新文献

{"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":"Potholes and shear zones deformation in sandstones: Central Amazon basin","authors":"Carlos Alejandro Salazar ,&nbsp;Roberto Cesar de Mendonça Barbosa ,&nbsp;Isabela Apoema Gomes de Souza ,&nbsp;Marta Edith Velásquez David ,&nbsp;Andressa Resende Soares ,&nbsp;Diego Wenderson Venâncio","doi":"10.1016/j.jsames.2025.105435","DOIUrl":"10.1016/j.jsames.2025.105435","url":null,"abstract":"<div><div>A pothole is a form related to morphogenetic processes that occur in rock outcrops (such as granites), which are particularly susceptible to water physical and chemical weathering processes, generally in humid tropical climates. In the center of the Amazon basin, waterfalls, rapids streams, and knickzones with the development of potholes, are formed in the beds of several rivers (Urubuí and their tributaries) that erode sandstones from the Silurian Nhamundá Formation. To elucidate the origin of these potholes, there are highlights on analyzing the susceptibility to erosion processes, variations in texture, mineral composition, and strain deformation recorded in quartzarenite to subarkosic sandstones. Panholes are observed and associated with knickzones, where ruptile dextral simple shear zone systems and their conjugate structures influence the drainage network. This search shows that the potholes are spatially positioned at the intersections of tectonic structures which, in addition to the dissolution processes of the sandstone framework, allow the development of large-scale potholes, such as in the Mutum waterfall. They were formed by morphodynamic processes in river valleys carved out of the Nhamundá Formation.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105435"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520562","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}

{"title":"Nitrogen and phosphorus cycling in the hyporheic zone: A scientometric approach to research in Brazil","authors":"Thalia Veronica Lazo Campos ,&nbsp;Jéssica Carneiro de Souza ,&nbsp;Daniela Mariano Lopes da Silva","doi":"10.1016/j.jsames.2025.105441","DOIUrl":"10.1016/j.jsames.2025.105441","url":null,"abstract":"<div><div>Hyporheic zone, due to its constant contact with water flows, plays a crucial role in nutrient cycling. Despite global advances in understanding the hyporheic zone, its importance, functions, fauna, and the ecological processes that occur there, there are still areas that require further investigation, both in Brazil and internationally. This study conducted a scientometric analysis of research on nutrients, specifically nitrogen and phosphorus, in the hyporheic zone, focusing on its temporal and geographical evolution. The main journals, authors, countries, and research lines were identified, with a particular focus on Brazil. A total of 483 articles related to nitrogen and 238 to phosphorus were selected and analyzed using the VOSviewer software. The results showed growing interest over the past two decades, with the United States, several European countries (the United Kingdom, Germany, Spain, France, among others), and China being the main contributors to this research, although there are still unexplored biomes and ecosystems. The analysis of graphs and networks revealed the presence of small research groups that are not well connected. Additionally, it was observed that studies on nitrogen are more abundant and multidisciplinary compared to those on phosphorus. In Brazil, most of the few studies were conducted in the last seven years. This work provides a solid foundation for future research on biogeochemical processes in the hyporheic zone.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105441"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520500","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":"Volume Special Issue Tectonostratigraphic Evolution of Patagonia: Preface","authors":"Pablo D. González ,&nbsp;Nicolás Foix ,&nbsp;José O. Allard ,&nbsp;Mariano Hernández","doi":"10.1016/j.jsames.2025.105439","DOIUrl":"10.1016/j.jsames.2025.105439","url":null,"abstract":"<div><div>This Volume Special Issue of the Journal of South American Earth Sciences is dedicated to honoring the career of Professor Dr. Raúl Eduardo Giacosa, a distinguished geologist in Stratigraphy, Structural Geology, and Tectonics of Patagonia, Argentina. Throughout his tenure at the Servicio Geológico Minero Argentino (SEGEMAR), Dr. Giacosa has made pioneering contributions to various topics, including basement geology, stratigraphy of the volcano-sedimentary cover, brittle-to-ductile deformation, structural and kinematic analysis, tectonics, and related mineral resources of Patagonia. His dedication, innovative research, and steadfast mentorship have profoundly impacted the field, leaving a lasting legacy that inspires future generations. This special issue pays tribute to his remarkable achievements and extends heartfelt gratitude for his enduring influence and the contributions of all who made this issue possible.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105439"},"PeriodicalIF":1.7,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474410","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":"Spatial prediction of soil salinity: Remote sensing and machine learning approach","authors":"Thenmozhi Thangarasu ,&nbsp;Hanan Abdullah Mengash ,&nbsp;Randa Allafi ,&nbsp;Hany Mahgoub","doi":"10.1016/j.jsames.2025.105440","DOIUrl":"10.1016/j.jsames.2025.105440","url":null,"abstract":"<div><div>Soil salinity significantly affects agricultural productivity and land sustainability, necessitating efficient monitoring and predictive strategies. This study leverages remote sensing data and machine learning algorithms to spatially predict soil salinity across the Puerto Vallarta region, covering an area of 716.03 km². To enhance prediction accuracy, a diverse set of indices were employed, including Salinity Indices (SI 1, SI 2, SI 3, and SI 11), Intensity Indices (INT 1 and INT 2), Brightness Index (BI), Soil-Adjusted Vegetation Index (SAVI), Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI), and the ratio of spectral bands (B2 and B5). These indices deliver appreciated understandings into soil and vegetation properties, allowing accurate classification and salinity assessment. Soil salinity was categorized into five classes: Very Low (16.54%), Low (23.16%), Moderate (21.97%), High (19.95%), and Very High (18.38%). The machine learning models employed for this study included Random Forest (RF), Artificial Neural Network (ANN), and Support Vector Machine (SVM). Among these, RF exhibited the highest prediction accuracy (92.1%), followed by ANN (89.5%) and Support Vector Machine (86.2%). These results underscore the potential of RF as a robust tool for analyzing spatially complex environmental datasets. Integrating remote sensing parameters and machine learning algorithms demonstrates an effective approach for mapping and managing soil salinity. The findings support sustainable land management by pinpointing critical salinity zones that need urgent intervention. Furthermore, the methodology established in this learning can be practical to other regions facing parallel challenges. This research highlights the significance of data-driven approaches in environmental monitoring and resource management.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"156 ","pages":"Article 105440"},"PeriodicalIF":1.7,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471154","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}