Mariana Meireles Leite , Tiago Amâncio Novo , Humberto Reis , Tobias Fonte Boa , Fernanda Moura Costa , Deniro Felipe Gonçalves Costa
{"title":"Interplay between structural framework and diagenetic processes in the Barra Velha Formation: A study from Tupi Field, Santos Basin, Brazil","authors":"Mariana Meireles Leite , Tiago Amâncio Novo , Humberto Reis , Tobias Fonte Boa , Fernanda Moura Costa , Deniro Felipe Gonçalves Costa","doi":"10.1016/j.jsames.2025.105733","DOIUrl":"10.1016/j.jsames.2025.105733","url":null,"abstract":"<div><div>The Cretaceous pre-salt reservoirs of the eastern Brazilian passive margin basins store major oil and gas reserves, representing some of the most significant hydrocarbon discoveries of recent decades. Despite extensive research, critical questions remain about their depositional nature, post-depositional evolution, and tectonic controls. This study integrates seismic interpretation, structural restoration, petrographic analysis, and well data to reconstruct the tectono-stratigraphic architecture of the Tupi Field, Santos Basin, and assess its implications for reservoir compartmentalization and fluid flow dynamics.</div><div>The results indicate that the Tupi High functioned as a persistent structural high throughout successive rifting episodes, controlling sediment distribution and basin compartmentalization. During Rift II, an increase in crustal stretching toward the south played a key role in generating erosional or non-depositional features in northern sectors. Structural restoration and interpreted subsidence patterns support a continued tectonic influence during Rift III, extending fault activity into the upper Barra Velha Formation (BVF). These findings also reveal that deposition occurred across a mosaic of shallow, interconnected lakes, rather than a single large lacustrine system.</div><div>The diagenetic evolution of the BVF is marked by early calcite cementation, multiple dissolution episodes, dolomitization, and later silica cementation. Diagenetic patterns are primarily governed by sedimentary facies and stratigraphic position, but are also influenced by structural architecture. Mud-rich, low-permeability intervals exhibit dominant early diagenetic features with limited mineral replacement, whereas structurally elevated zones show intense late-stage diagenesis—including saddle dolomite, late dissolution, and hydrothermal quartz—associated with fault-related fluid circulation. Continued fault activity up to the top of Rift III likely enhanced vertical fluid migration. A south-to-north gradient in subsidence may have promoted fluid expulsion toward structurally higher domains post-deposition. Local controls, such as original mineralogy, facies interbedding, and porosity variability, further contributed to the observed heterogeneity.</div><div>These findings demonstrate that BVF reservoir quality reflects the multiscale interplay between depositional and tectonic architecture, early and late diagenetic processes, and post-depositional fluid dynamics—critical factors for pre-salt exploration and production strategies.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"166 ","pages":"Article 105733"},"PeriodicalIF":1.5,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144852732","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":"Oxyodontherium zeballosi Ameghino, 1883 (Panperissodactyla, Litopterna, Macraucheniidae) from the Neogene of Uruguay","authors":"A. Corona, A.C. Badín, D. Perea","doi":"10.1016/j.jsames.2025.105730","DOIUrl":"10.1016/j.jsames.2025.105730","url":null,"abstract":"<div><div>Macraucheniidae comprises middle to large-sized herbivores characterized by an elongated skull, neck, and limbs. Diagnostic features of the family include a mesaxonic foot with three functional digits, a vertebral artery canal passing through the neural arch of most cervical vertebrae, and a third trochanter on the femur. This contribution provides a full comparative description of a macraucheniid mandible from an adult specimen recovered from Neogene strata in Kiyú, San José Department, Uruguay. The specimen exhibits several features consistent with an assignment to <em>Oxyodontherium zeballosi</em>, as follows: the m1 and m2 with fairly acute labial edges of mesial and distal lobes; talonid wider than trigonid, with thin entoconid linked to the hypolophid by an entolophid; hypolophid long and oblique; m3 with shorter trigonid, wide ectoflexid, and no entoconid non entolophid; low mandibular ramus of uniform high from anterior to posterior end. For further comparisons, an analysis of the holotype of <em>Oxyodontherium zeballosi</em> was performed using CT scans. This new specimen is significant because it represents the most complete mandible of the species reported to date, substantially improving our morphological knowledge. Additionally, it constitutes the first reliable record of <em>O. zeballosi</em> in Uruguay, extending the species geographic distribution to its most southeastern boundary. This species, previously reported only from Entre Ríos and San Luis provinces in Argentina, increases the known macraucheniid diversity in the Neogene of Uruguay, which is currently under investigation.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"166 ","pages":"Article 105730"},"PeriodicalIF":1.5,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144866560","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}
Deniro Costa , Tiago Novo , Tobias Fonte-Boa , Ross Stevenson , Humberto Reis , Galen Halverson
{"title":"Tectonic influence and isotopic signature of pre-salt lacustrine carbonates in the Tupi field, Santos Basin","authors":"Deniro Costa , Tiago Novo , Tobias Fonte-Boa , Ross Stevenson , Humberto Reis , Galen Halverson","doi":"10.1016/j.jsames.2025.105734","DOIUrl":"10.1016/j.jsames.2025.105734","url":null,"abstract":"<div><div>Fault networks in the Santos Basin play a key role in controlling depositional environmental conditions for sedimentation of the Barra Velha Formation. This work investigates how fault activity and reactivation affect the pre-salt carbonates and influence element distribution, integrating seismic interpretation, structural restoration and geochemical analyses for major elements (Ca, Mg, Sr, Fe, Mn) and isotopes (δ<sup>13</sup>C, δ<sup>18</sup>O, <sup>87</sup>Sr/<sup>86</sup>Sr). Results reveal three dominant fault sets (NNW-SSE, N-S, NNE-SSW), with significant deformation in the central sector of the Iracema region indicated by section restoration. Isotopic data of δ<sup>13</sup>C (0.79 ‰–3.16 ‰) and δ<sup>18</sup>O (−1.22 ‰–3.86 ‰) from the studied well are consistent with other fields in the basin, which reflects that regional control overcomes local tectonic impact on deposition. However, the lacustrine depositional setting is described with episodic environmental changes as Fe and Mn present extreme outlier values and faults may influence Sr mobilization in fluid migration. The <sup>87</sup>Sr/<sup>86</sup>Sr values (0.7130–0.7144) suggest a dominant felsic continental source, with minor volcanic input. These findings reinforce the role of faulting in controlling element mobility and the structural evolution of pre-salt carbonates in the Tupi field.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105734"},"PeriodicalIF":1.5,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829546","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":"Impacts of land cover on surface temperature in a meandering river basin, Minas Gerais, Brazil","authors":"Ítalo Rafael Costa de Mira , Márcio Luiz da Silva","doi":"10.1016/j.jsames.2025.105736","DOIUrl":"10.1016/j.jsames.2025.105736","url":null,"abstract":"<div><div>The ongoing replacement of natural vegetation with impervious surfaces, driven by urban expansion and human activity, has led to significant alterations in local microclimates and thermal comfort conditions. Understanding land surface temperature (LST) is essential for informing public policies that guide territorial planning and support sustainable environmental management. This study examines LST variations in the Alto-Médio Rios Mogi Guaçu and Pardo Basin, located in southern Minas Gerais, Brazil, using Landsat-8 imagery from September 2015 and 2023, two of the hottest years ever recorded in the country. Notably, the analysis integrates the combined effects of land cover, vegetation, and solar radiation on local thermal dynamics—an approach rarely applied to medium-sized tropical watersheds. Findings reveal that more than a quarter of the study area experienced an average LST increase of approximately 5 °C, with some zones showing increases exceeding 10 °C. The most affected areas correspond to regions characterized by intensive anthropogenic land use, vegetation loss, and high solar radiation. In contrast, areas with well-preserved native vegetation maintained lower surface temperatures, even under high solar exposure. The study underscores the vital role of vegetation cover in moderating soil temperatures and reinforces the urgent need for sustainable land-use practices to mitigate the impacts of local climate change.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"166 ","pages":"Article 105736"},"PeriodicalIF":1.5,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889241","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}
Ramón Yosvanis Batista Cruz , Felipe de Jesús López Saucedo , Frida Mariana Muzquiz Esquivel , José Alberto Batista Rodríguez , Yuri Almaguer Carmenates , Yalina Montecelos Zamora , Alberto Hernández Rosales , Luis Eutiquio Canales Gutiérrez
{"title":"Water reservoirs in open coal pits: A useful resource for NE of Mexico?","authors":"Ramón Yosvanis Batista Cruz , Felipe de Jesús López Saucedo , Frida Mariana Muzquiz Esquivel , José Alberto Batista Rodríguez , Yuri Almaguer Carmenates , Yalina Montecelos Zamora , Alberto Hernández Rosales , Luis Eutiquio Canales Gutiérrez","doi":"10.1016/j.jsames.2025.105731","DOIUrl":"10.1016/j.jsames.2025.105731","url":null,"abstract":"<div><div>Coal mining remains an essential component of the energy matrix in many countries worldwide. In Mexico, the Sabinas Basin represents one of the most intensively exploited coal regions for several decades. As a result, the landscape has been significantly altered, leading to the formation of numerous water reservoirs within depressions created by mining activities. Despite their extent, these reservoirs have received limited attention from hydrochemical perspectives. In this study, we conducted a digital mapping of these reservoirs, characterized their physical attributes, and assessed water quality in eighteen reservoirs and two wells. Our findings reveal that the water exhibits a low quality, characterized by elevated concentrations of sulfates (up to 1982 mg/L), chlorides (up to 1197 mg/L), iron (up to 64.7 mg/L), total dissolved solids (up to 6432 ppm), and hardness (up to 3084 mg/L). Nevertheless, this water may be suitable for irrigation in crops or soils capable of assimilating high sulfate levels. The conceptual model summarizes the mechanisms and processes responsible for the progressive flooding of these mining-induced depressions, as well as the resulting physicochemical characteristics of the accumulated water. The hydrochemistry appears to reflect a combination of surface and groundwater interactions influenced by mining operations, including the disturbance of geological strata, natural processes (e.g., erosion, leaching, and landslides), hydrological and climatic factors, and water–rock interactions involving shallow aquifers and carbonaceous sequences containing sulfide, sulfate minerals, and salts. Excess sulfate can be treated by various methods, which would allow a significant volume of these resources to be available for various uses. Other ecological and environmental services should be evaluated in the future to take advantage of these vital spaces.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105731"},"PeriodicalIF":1.5,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829547","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}
Lucas Henrique Batista da Silva , Renato Rodriguez Cabral Ramos , Marcelo de Araújo Carvalho
{"title":"Integrated facies and petrographic analysis of the Whisky Bay Formation (Albian–Turonian), Larsen Basin, James Ross Island, Antarctica: depositional systems and arc-sourced detritus","authors":"Lucas Henrique Batista da Silva , Renato Rodriguez Cabral Ramos , Marcelo de Araújo Carvalho","doi":"10.1016/j.jsames.2025.105719","DOIUrl":"10.1016/j.jsames.2025.105719","url":null,"abstract":"<div><div>This study presents an integrated facies and petrographic analysis of the Albian–Turonian Whisky Bay Formation (Gustav Group, Larsen Basin) on James Ross Island, Antarctica, to reconstruct depositional systems and evaluate arc-derived detrital input. Two stratigraphic profiles (totaling 130 m) were analyzed alongside petrographic data from 30 sandstone and rudite samples. Three lithofacies associations (FA1–FA3) were identified: (1) slope-apron breccias and sandstones (FA1), formed by debris flows and low-density turbidity currents linked to fault-scarp erosion; (2) sand-rich turbidites (FA2), deposited by high-efficiency turbidity currents through slope-attached canyons; and (3) volcaniclastic submarine fans (FA3), dominated by volcaniclastic conglomerates sourced from active arc magmatism. Petrographic data reveal lithic sandstones dominated by volcanic fragments (75–88 %), fresh plagioclase, and minor quartz/metasedimentary clasts, indicating provenance from the Antarctic Peninsula Volcanic Group (APVG) and Trinity Peninsula Group (TPG). Provenance-tectonic linkages highlight syn-sedimentary faulting and Aptian–Turonian arc flare-ups during Cretaceous evolution of the Larsen Basin. The stratigraphic transition from fault-driven aprons (FA1) to volcaniclastic fans (FA3) reflects a tectonostratigraphic system controlled by alternating differential subsidence and arc magmatism dynamics.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105719"},"PeriodicalIF":1.5,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144780959","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}
Abner A. Calle Salcedo , Gabriela A. Cisterna , Karen Halpern
{"title":"New taxa of Pennsylvanian productide brachiopods from west-central Argentina: Implications for biostratigraphy and paleobiogeography in the Tivertonia jachalensis-Streptorhynchus inaequiornatus Zone","authors":"Abner A. Calle Salcedo , Gabriela A. Cisterna , Karen Halpern","doi":"10.1016/j.jsames.2025.105727","DOIUrl":"10.1016/j.jsames.2025.105727","url":null,"abstract":"<div><div>Two new species of productide brachiopods are described from the Carboniferous Quebrada Larga Formation, San Juan Province, in the Río Blanco Basin, Argentina: <em>Brachiosvalbardia archboldi</em> sp. nov. and <em>Coronalosia vergelae</em> sp. nov. These new species increase the known brachiopod diversity of the <em>Tivertonia jachalensis</em>-<em>Streptorhynchus inaequiornatus</em> Zone (<em>TS</em>, Moscovian-Kasimovian?) and contribute to the analysis of its compositional variations and distribution patterns across the central western Argentinian basins (i.e., Western Paganzo, Río Blanco, Calingasta-Uspallata, and San Rafael basins). Analysis of an occurrence database of brachiopods from the <em>TS</em> Fauna, including 22 genera from 13 localities in these basins, were grouped into three major groups that allow the identification of compositional variations along the north-south latitudinal gradient. This diversity pattern is also influenced by environmental features (i.e., bathymetric gradient and nutrient availability) related to the climatic amelioration registered in this part of Gondwana during the late Carboniferous-early Permian interval.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"166 ","pages":"Article 105727"},"PeriodicalIF":1.5,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144860973","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}
Vittor Cambria , Diego L. Nascimento , Luciano Alessandretti , Caio C. Rangel , Daniel Sedorko
{"title":"Root trace fossils as indicators of biogeomorphological stages in a Cretaceous fluvial system: Insights from the Sanfranciscana basin","authors":"Vittor Cambria , Diego L. Nascimento , Luciano Alessandretti , Caio C. Rangel , Daniel Sedorko","doi":"10.1016/j.jsames.2025.105724","DOIUrl":"10.1016/j.jsames.2025.105724","url":null,"abstract":"<div><div>Rhizoliths, or root traces, are key indicators of subaerial exposure and vegetation colonization in ancient continental settings, yet they remain underexplored compared to invertebrate trace fossils. This study investigates rhizolith and invertebrate ichnofabrics within the Capacete Formation (Campanian, Sanfranciscana Basin, SE Brazil), aiming to reconstruct aspects of fluvial biogeomorphological succession and paleoenvironmental dynamics. Detailed sedimentological and ichnological analyses were conducted across a succession of channel, lateral accretion, crevasse splay, and floodplain deposits. Rhizoliths, including root casts and rhizohaloes, were most abundant in paleosols developed on floodplain fines, whereas invertebrate trace fossils such as <em>Scoyenia, Taenidium,</em> and <em>Macanopsis</em> occur in association with both overbank and sandy bar deposits. The ichnofabrics record a range of colonization phases, reflecting variable hydrogeomorphic regimes and vegetation stabilization states. The data suggests a close correspondence with the fluvial biogeomorphological succession model (FBS), with ichnofossils representing different stages of fluvial bar stabilization and floodplain forest maturation. These results provide high-resolution insight into ancient riparian ecosystem dynamics, sedimentary cyclicity, and landscape evolution in a meandering fluvial system.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105724"},"PeriodicalIF":1.5,"publicationDate":"2025-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766640","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}
José Francisco da Cruz Neto , Francisco Charles dos Santos Silva , Carlos André Alves de Souza , Alexandre Maniçoba da Rosa Ferraz Jardim , Wilma Roberta dos Santos , Lady Daiane Costa de Sousa Martins , Wagner Martins dos Santos , Alan Mario Zuffo , Thieres George Freire da Silva
{"title":"Validation of a desertification monitoring model in a semiarid region with the support of machine learning techniques","authors":"José Francisco da Cruz Neto , Francisco Charles dos Santos Silva , Carlos André Alves de Souza , Alexandre Maniçoba da Rosa Ferraz Jardim , Wilma Roberta dos Santos , Lady Daiane Costa de Sousa Martins , Wagner Martins dos Santos , Alan Mario Zuffo , Thieres George Freire da Silva","doi":"10.1016/j.jsames.2025.105715","DOIUrl":"10.1016/j.jsames.2025.105715","url":null,"abstract":"<div><div>Desertification is a global and concerning phenomenon resulting from the interplay of climatic factors, inadequate human activities, and unsustainable use of natural resources. Its historical roots are linked to intensive agriculture, deforestation, and land-use changes, making the development of mathematical models crucial to sustainably identify and manage these areas. These models incorporate variables such as climatic patterns, land use, and degradation indicators, enabling an accurate assessment of the risk and extent of desertification in specific regions. The objective of this study was to evaluate the effectiveness of the RisDes_Index model in identifying areas affected by desertification and assessing the severity of environmental degradation. The model was developed based on orbital information and in situ data collected from Caatinga environments, wetlands, and areas undergoing desertification. The study was conducted in the Sertão Central region of Brazil, covering the municipalities of Floresta, Cabrobó, Belém do São Francisco, Carnaubeira da Penha, Itacuruba, and Orocó—an area known to be affected by desertification. The model demonstrated high efficacy in identifying desertified environments. One key feature that allows the RisDes_Index model to be applied to various global regions is its low computational power requirement, unlike machine learning and random forests, which, despite their high identification capacity, demand significant computational resources. However, the RisDes_Index model requires a higher operational capacity from researchers, which may render certain studies unfeasible due to a lack of necessary data. No correlations were found between the RisDes_Index model and vegetation indices (NDVI, SAVI, LAI, albedo, TGSI, and TSoil).</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105715"},"PeriodicalIF":1.5,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144757951","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":"Crocodyliforms of the São José do Rio Preto Formation (Bauru Basin, Upper Cretaceous), taxonomic and preservational aspects","authors":"Fabiano Vidoi Iori , Thiago da Silva Marinho , Leonardo Silva Paschoa , Renan Oliveira Fernandes , Sandra Simionato Tavares , Felipe Chinaglia Montefeltro","doi":"10.1016/j.jsames.2025.105718","DOIUrl":"10.1016/j.jsames.2025.105718","url":null,"abstract":"<div><div>The São José do Rio Preto Formation (Upper Cretaceous, Bauru Basin) contains a rich vertebrate fossil assemblage, primarily composed of isolated remains of fish, chelonians, crocodyliforms, and dinosaurs. We report the newly discovered specimens of crocodyliforms (cranial and mandibular bones, osteoderms, and teeth) and review the previously described specimens of this clade. Our investigations point to the presence of four distinct clades in this formation: <em>Baurusuchidae</em>, <em>Peirosauridae</em>, <em>Sphagesauria</em>, and <em>Itasuchidae</em>. Xenodontosuchians (i.e., <em>Baurusuchidae</em> + <em>Sphagesauridae</em>) are rare; most of the fossils are identified as <em>Itasuchidae</em>, with at least at two taxa present in the formation, <em>Epoidesuchus</em> and the new species <em>Ibirasuchus gelcae</em> gen. et. sp. nov. Among the reviewed specimens, we reidentified a set of six isolated teeth previously attributed to the family <em>Candidodontidae</em> as belonging to the order <em>Sphagesauria</em>. The fluvial-lacustrine nature of the depositional environment of the São José do Rio Preto Formation likely contributed to the diversity and abundance of itasuchids, a taxon considered to be semi-aquatic. The occupation of distinct environments and ecological niches by <em>Xenodontosuchia</em> and itasuchids may indicate that their paleoecology has directly influenced their preservation processes and, consequently, that this aspect should be taken into consideration when analyzing the crocodyliform diversity in the Bauru Basin.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"165 ","pages":"Article 105718"},"PeriodicalIF":1.5,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144780958","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}