Pub Date : 2025-12-03DOI: 10.1016/j.jsames.2025.105903
M. San Juan , T. Villaseñor , D. Dintrans
Mountain catchments are dynamic sedimentary systems where climate variability significantly affects geomorphic processes and sediment connectivity. This study investigates the processes of sediment generation and transfer in the Volcán River basin in central Chile's semi-arid Andes, a region impacted by a prolonged megadrought since 2010. We combined geomorphological mapping, sediment connectivity modelling using the Index of Connectivity (IC), and sediment geochemistry analysis of suspended sediments collected during spring-summer season of 2022–2023. Geomorphological mapping identified seven distinct morphogenetic environments (morphostructural, volcanic, glacial, fluvial, denudational, glacial ice and anthropogenic), each contributing variably to sediment transfer. IC analysis revealed spatial heterogeneity in sediment connectivity, with higher values in fluvial and denudational domains and lower values in glacial and volcanic areas. Geochemical analysis of rare earth elements (REE) in suspended sediments indicated that Cenozoic volcanic formations, especially from subglacial sources, are the primary sediment contributors under current hydrological conditions, with Mesozoic units contributing episodically during high-magnitude events like debris flows. Under this scheme, surficial glacial and volcanic morphogenetic domains act as sediment buffers due to their distance to the main fluvial channels as well as morphology that promotes sediment accumulation. In contrast, high melt rates of the glaciers in the valley enhance subglacial connectivity to the fluvial network in the context of the megadrought, while mass wasting events act as sources for short-term sediment pulses during high runoff events. These findings highlight how sediment coupling and provenance in mountain basins are modulated by both the current megadrought and extreme hydrometeorological events. The results provide insights for hazard assessment and sediment management in mountainous regions experiencing climatic stress.
{"title":"The megadrought modulation of sediment transfer in the Volcán River basin (33°S), semi-arid Andes","authors":"M. San Juan , T. Villaseñor , D. Dintrans","doi":"10.1016/j.jsames.2025.105903","DOIUrl":"10.1016/j.jsames.2025.105903","url":null,"abstract":"<div><div>Mountain catchments are dynamic sedimentary systems where climate variability significantly affects geomorphic processes and sediment connectivity. This study investigates the processes of sediment generation and transfer in the Volcán River basin in central Chile's semi-arid Andes, a region impacted by a prolonged megadrought since 2010. We combined geomorphological mapping, sediment connectivity modelling using the Index of Connectivity (IC), and sediment geochemistry analysis of suspended sediments collected during spring-summer season of 2022–2023. Geomorphological mapping identified seven distinct morphogenetic environments (morphostructural, volcanic, glacial, fluvial, denudational, glacial ice and anthropogenic), each contributing variably to sediment transfer. IC analysis revealed spatial heterogeneity in sediment connectivity, with higher values in fluvial and denudational domains and lower values in glacial and volcanic areas. Geochemical analysis of rare earth elements (REE) in suspended sediments indicated that Cenozoic volcanic formations, especially from subglacial sources, are the primary sediment contributors under current hydrological conditions, with Mesozoic units contributing episodically during high-magnitude events like debris flows. Under this scheme, surficial glacial and volcanic morphogenetic domains act as sediment buffers due to their distance to the main fluvial channels as well as morphology that promotes sediment accumulation. In contrast, high melt rates of the glaciers in the valley enhance subglacial connectivity to the fluvial network in the context of the megadrought, while mass wasting events act as sources for short-term sediment pulses during high runoff events. These findings highlight how sediment coupling and provenance in mountain basins are modulated by both the current megadrought and extreme hydrometeorological events. The results provide insights for hazard assessment and sediment management in mountainous regions experiencing climatic stress.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105903"},"PeriodicalIF":1.5,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694606","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}
Pub Date : 2025-12-03DOI: 10.1016/j.jsames.2025.105902
Beatriz Aguirre-Urreta
This research describes the earliest paleontological reports from the High Andes of Argentina and Chile, dating back to the mid-19th and early 20th centuries. They were largely based on observations made during geological and exploratory expeditions. These investigations are ordered chronologically, and although often limited by logistical challenges, documented the presence of marine Mesozoic invertebrate fossils from strata exposed at high altitudes. The first records are due to John Gillies, and not to Joseph Pentland as said for many years, though their importance was unfortunately ignored. Franz Meyen and Charles Darwin deserve a central place among the earliest naturalists who contributed to the paleontology of the region. Following those pioneering observations, Alfred Stelzner played a key role in the second half of the 19th century by integrating paleontological data into regional geological mapping. A generation later, Walther Schiller, carried out some of the most systematic paleontological and stratigraphic investigations of the High Andes where he correlated marine fossil assemblages with tectonic structures.
{"title":"A review of 100 years of paleontological research in the Highest Andes","authors":"Beatriz Aguirre-Urreta","doi":"10.1016/j.jsames.2025.105902","DOIUrl":"10.1016/j.jsames.2025.105902","url":null,"abstract":"<div><div>This research describes the earliest paleontological reports from the High Andes of Argentina and Chile, dating back to the mid-19th and early 20th centuries. They were largely based on observations made during geological and exploratory expeditions. These investigations are ordered chronologically, and although often limited by logistical challenges, documented the presence of marine Mesozoic invertebrate fossils from strata exposed at high altitudes. The first records are due to John Gillies, and not to Joseph Pentland as said for many years, though their importance was unfortunately ignored. Franz Meyen and Charles Darwin deserve a central place among the earliest naturalists who contributed to the paleontology of the region. Following those pioneering observations, Alfred Stelzner played a key role in the second half of the 19th century by integrating paleontological data into regional geological mapping. A generation later, Walther Schiller, carried out some of the most systematic paleontological and stratigraphic investigations of the High Andes where he correlated marine fossil assemblages with tectonic structures.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"171 ","pages":"Article 105902"},"PeriodicalIF":1.5,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145799275","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}
Pub Date : 2025-12-03DOI: 10.1016/j.jsames.2025.105899
Roberto González-Vidal , Felipe Tapia , Fernando Poblete , Matías Peña , Esteban Salazar , Valentina Ríos
Navarino Island is located in the southernmost part of South America, within the Central Belt of the Fuegian Orogen. The shortening of the geological units observed on the island is believed to be related to a compressional event during the closure of the Rocas Verdes Basin. However, the full extent of this relationship remains unclear due to accessibility challenges and the apparent change in the stratigraphic records both north and south of the Beagle Channel. In this study, we integrate anisotropy of magnetic susceptibility (AMS) with structural observations across turbiditic sandstones and mudstones from the Lower Cretaceous Yahgan Formation. We analyzed thirty new sampling sites located along the northern coast of the island and the Dientes de Navarino mountain group. The AMS data exhibited predominantly oblate magnetic fabrics, with P′ values ranging from 1.02 to 2.22. The ellipsoid orientations correlated well with the structural features, particularly cleavage (S1) and fold axes. High P′ values and tectonic fabric types were concentrated in the western part of the island. A transition from a tectonic fabric with lower anisotropy degrees to a more sedimentary fabric was observed towards the east and south. These findings reflect a W-E deformation gradient consistent with the island's structural features, including an overprinting cleavage family (S2) restricted to the island's northwest. This study highlights the utility of AMS in elucidating strain directions and reconstructing deformation histories in complex orogenic settings.
{"title":"Compressional tectonics related to Fuegian orogeny: Insights from AMS and structural geology in Navarino Island, Chile","authors":"Roberto González-Vidal , Felipe Tapia , Fernando Poblete , Matías Peña , Esteban Salazar , Valentina Ríos","doi":"10.1016/j.jsames.2025.105899","DOIUrl":"10.1016/j.jsames.2025.105899","url":null,"abstract":"<div><div>Navarino Island is located in the southernmost part of South America, within the Central Belt of the Fuegian Orogen. The shortening of the geological units observed on the island is believed to be related to a compressional event during the closure of the Rocas Verdes Basin. However, the full extent of this relationship remains unclear due to accessibility challenges and the apparent change in the stratigraphic records both north and south of the Beagle Channel. In this study, we integrate anisotropy of magnetic susceptibility (AMS) with structural observations across turbiditic sandstones and mudstones from the Lower Cretaceous Yahgan Formation. We analyzed thirty new sampling sites located along the northern coast of the island and the Dientes de Navarino mountain group. The AMS data exhibited predominantly oblate magnetic fabrics, with P′ values ranging from 1.02 to 2.22. The ellipsoid orientations correlated well with the structural features, particularly cleavage (S<sub>1</sub>) and fold axes. High P′ values and tectonic fabric types were concentrated in the western part of the island. A transition from a tectonic fabric with lower anisotropy degrees to a more sedimentary fabric was observed towards the east and south. These findings reflect a W-E deformation gradient consistent with the island's structural features, including an overprinting cleavage family (S<sub>2</sub>) restricted to the island's northwest. This study highlights the utility of AMS in elucidating strain directions and reconstructing deformation histories in complex orogenic settings.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105899"},"PeriodicalIF":1.5,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694608","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}
Pub Date : 2025-12-03DOI: 10.1016/j.jsames.2025.105900
Gabriela A. Gonzalez-Liedtke , Matías M. Morales Cámera , Juan A. Dahlquist , Sebastián Rocher , Juan C. Harasimiuk , Gilmara Santos da Cruz , Pablo H. Alasino , Juan A. Moreno
Felsic microgranitoid enclaves (FMEs) are underexplored components of granitic plutons that preserve key evidence of magma chamber processes. This study examines FMEs and the coexisting fine-grained units in relation to the porphyritic regional granites that host them within the Characato suite of the Achala Intrusive Complex, Argentina, integrating field observations, petrography, whole-rock geochemistry, mineral chemistry, and Nd isotope analyses.
Our main conclusions indicate that the FMEs and associated fine-grained units represent autolithic fragments derived from solidification fronts within granitic magma chambers. Their finer grain size and relatively higher crystallization temperatures (e.g., ΔTZr ≈ 60 °C and ΔTBt ≈ 40 °C) suggest early crystallization under enhanced undercooling conditions near chamber margins.
Field evidence -such as spatial association of FMEs with marginal fine-grained units, gradational contacts, ductile felsic dykes, and magmatic layering and deformation-indicates multiple episodes of solidification front collapse into the host magma. The observed diversity in enclave size, texture, and degree of interaction reflects a continuum of rheological states, ranging from crystal-rich suspensions to partially solidified mushes.
Furthermore, the neodymium isotopic compositions and geochemical trends of the FMEs and marginal fine-grained units are consistent with those of the regional host granites. This supports a cogenetic and crustal origin, with the enclaves and associated lithologies representing more primitive crystallization products.
This study emphasizes the dynamic role of solidification fronts as zones of instability, and magmatic recycling, contributing to the construction and internal evolution of felsic plutonic systems.
{"title":"Felsic microgranitoid enclaves as records of solidification front collapse in silicic magma chambers: Insights from the Devonian Characato suite (Achala Intrusive Complex, Argentina)","authors":"Gabriela A. Gonzalez-Liedtke , Matías M. Morales Cámera , Juan A. Dahlquist , Sebastián Rocher , Juan C. Harasimiuk , Gilmara Santos da Cruz , Pablo H. Alasino , Juan A. Moreno","doi":"10.1016/j.jsames.2025.105900","DOIUrl":"10.1016/j.jsames.2025.105900","url":null,"abstract":"<div><div>Felsic microgranitoid enclaves (FMEs) are underexplored components of granitic plutons that preserve key evidence of magma chamber processes. This study examines FMEs and the coexisting fine-grained units in relation to the porphyritic regional granites that host them within the Characato <em>suite</em> of the Achala Intrusive Complex, Argentina, integrating field observations, petrography, whole-rock geochemistry, mineral chemistry, and Nd isotope analyses.</div><div>Our main conclusions indicate that the FMEs and associated fine-grained units represent autolithic fragments derived from solidification fronts within granitic magma chambers. Their finer grain size and relatively higher crystallization temperatures (e.g., ΔT<sub>Zr</sub> ≈ 60 °C and ΔT<sub>Bt</sub> ≈ 40 °C) suggest early crystallization under enhanced undercooling conditions near chamber margins.</div><div>Field evidence -such as spatial association of FMEs with marginal fine-grained units, gradational contacts, ductile felsic dykes, and magmatic layering and deformation-indicates multiple episodes of solidification front collapse into the host magma. The observed diversity in enclave size, texture, and degree of interaction reflects a continuum of rheological states, ranging from crystal-rich suspensions to partially solidified mushes.</div><div>Furthermore, the neodymium isotopic compositions and geochemical trends of the FMEs and marginal fine-grained units are consistent with those of the regional host granites. This supports a cogenetic and crustal origin, with the enclaves and associated lithologies representing more primitive crystallization products.</div><div>This study emphasizes the dynamic role of solidification fronts as zones of instability, and magmatic recycling, contributing to the construction and internal evolution of felsic plutonic systems.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"172 ","pages":"Article 105900"},"PeriodicalIF":1.5,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886270","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}
Pub Date : 2025-12-02DOI: 10.1016/j.jsames.2025.105896
Nazaré Suziane Soares , José Vidal de Figueiredo , Carlos Alexandre Gomes Costa , Italo Sampaio Rodrigues , José Carlos de Araújo
Transpiration, particularly in dryland forests, plays a major role in the water cycle. The one-million km2 Caatinga Biome is a data-scarce region in the Brazilian Semiarid, where rainy and dry season are clearly distinct. This work aims to measure the natural Caatinga vegetation transpiration using sap flow monitoring (between Feb 2016 and Dec 2017) and to validate the hydrological Distributed Catchment Scale Model (DiCaSM). Measured transpiration in situ was on overall average 0.58 mm.day−1 for rainy and transition seasons. There is evidence that sap flow does not provide a good representation of transpiration in dry seasons: sap flow is high, whereas, according to the Literature, actual evapotranspiration is negligible (<0.01 mm.day−1) due to a very low soil water content, and, thus, transpiration should also be negligible. Transpiration estimated by DiCaSM presented a well-defined seasonal variability, with values close to zero during the driest months, in agreement to previous literature. Overall, the findings contribute to better expertise regarding the transpiration rates in a dryland environment and may be used in water resources management contexts, as the transpiration process gives insight into local water use and availability.
{"title":"Forest transpiration in Brazilian drylands: measurement and validation of a hydrological model","authors":"Nazaré Suziane Soares , José Vidal de Figueiredo , Carlos Alexandre Gomes Costa , Italo Sampaio Rodrigues , José Carlos de Araújo","doi":"10.1016/j.jsames.2025.105896","DOIUrl":"10.1016/j.jsames.2025.105896","url":null,"abstract":"<div><div>Transpiration, particularly in dryland forests, plays a major role in the water cycle. The one-million km<sup>2</sup> Caatinga Biome is a data-scarce region in the Brazilian Semiarid, where rainy and dry season are clearly distinct. This work aims to measure the natural Caatinga vegetation transpiration using sap flow monitoring (between Feb 2016 and Dec 2017) and to validate the hydrological Distributed Catchment Scale Model (DiCaSM). Measured transpiration <em>in situ</em> was on overall average 0.58 mm.day<sup>−1</sup> for rainy and transition seasons. There is evidence that sap flow does not provide a good representation of transpiration in dry seasons: sap flow is high, whereas, according to the Literature, actual evapotranspiration is negligible (<0.01 mm.day<sup>−1</sup>) due to a very low soil water content, and, thus, transpiration should also be negligible. Transpiration estimated by DiCaSM presented a well-defined seasonal variability, with values close to zero during the driest months, in agreement to previous literature. Overall, the findings contribute to better expertise regarding the transpiration rates in a dryland environment and may be used in water resources management contexts, as the transpiration process gives insight into local water use and availability.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105896"},"PeriodicalIF":1.5,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694604","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}
Pub Date : 2025-12-02DOI: 10.1016/j.jsames.2025.105894
Olga Bohórquez-Orozco , Jhon Restrepo-Berrío , Héctor Mora-Páez
This study characterizes the present-day stress field of northwestern SouthAmerica using 337 focal mechanism solutions compiled from the Colombian Seismological Network, USGS, GEOFON, and GCMT catalogues. Based on seismicity depth, geographic proximity, and tectonic context, 30 stress regions were delineated, and their corresponding stress tensors were determined. The results reveal that compressional regimes dominate north of 5° N, where the maximum horizontal stress (SHmax) trends NW–SE, controlled by the convergence between the Panama–Choco Block and the North Andean Block. Southward, the regime transitions to strike-slip faulting with E–W-oriented SHmax, associated with right-lateral and conjugate fault systems. Along the Nazca Plate subduction front, pre-trench extensional regimes evolve into post-trench compressional settings within the accretionary prism. Intermediate-depth tensors in the Cauca and Bucaramanga sectors reveal an in-slab extensional axis for the former and NW–SE compression for the latter, where seismicity patterns support the presence of a detached Paleo-Caribbean slab. The stress tensor distribution confirms that the Panama–Choco–North Andean boundary is structurally complex, while the Eastern and Central Cordilleras display second-order transpressive regimes consistent with major crustal-scale faults.
Este estudio caracteriza el campo de esfuerzos actual de la esquina noroccidental de Suramérica, utilizando 337 soluciones de mecanismos focales compiladas de los catálogos de la Red Sismológica Nacional de Colombia, USGS, GEOFON y GCMT. Con base en la profundidad de la sismicidad, la proximidad geográfica y el contexto tectónico, se delimitaron 30 regiones de esfuerzo y se determinaron sus respectivos tensores. Los resultados revelan que los regímenes compresivos dominan al norte de los 5° N, donde el esfuerzo horizontal máximo (SHmax) tiene una orientación NW–SE, controlada por la convergencia entre el Bloque Panamá–Chocó y el Bloque Norandino. Hacia el sur, el régimen transiciona a fallamiento de tipo transcurrente con SHmax orientado E–O, asociado a sistemas de fallas dextrales y conjugadas. A lo largo del frente de subducción de la Placa de Nazca, los regímenes extensionales pre-fosa evolucionan hacia configuraciones compresivas pos-fosa dentro del prisma de acreción. Los tensores de profundidad intermedia en los sectores de Cauca y Bucaramanga revelan un eje extensional dentro de la losa para el primero y compresión NW–SE para el segundo, donde los patrones de sismicidad respaldan la presencia de una paleolosa Caribe desprendida. La distribución de los tensores de esfuerzo confirma que el límite entre los bloques Panamá–Chocó y Norandino es estructuralmente complejo, mientras que las cordilleras Oriental y Central exhiben regímenes transpresivos de segundo orden coherentes con fallas corticales de gran escala.
本研究利用哥伦比亚地震网、USGS、GEOFON和GCMT目录汇编的337个震源机制解，描述了南美洲西北部当前的应力场。根据地震活动深度、地理邻近度和构造背景，圈定了30个应力区，并确定了相应的应力张量。结果表明，在5°N以北以挤压体制为主，最大水平应力（SHmax）倾向于NW-SE，受巴拿马-乔科地块与北安第斯地块的辐合控制。向南转变为走滑断裂，东西向的大震区，并伴有右旋和共轭断裂系统。在纳斯卡板块俯冲前缘，增生三棱镜内的前海沟伸展构造演化为后海沟挤压构造。考卡和布卡拉曼加板块的中深度张量显示，前者为板块内伸展轴，后者为北西-东南挤压轴，地震活动模式支持古加勒比板块分离的存在。应力张量分布证实了巴拿马-乔科-北安第斯边界构造复杂，而科迪勒拉斯东部和中部表现出与大地壳尺度断裂相一致的二级逆压机制。哥伦比亚国家地质勘探局、哥伦比亚地质勘探局、哥伦比亚国家地质勘探局、哥伦比亚国家地质勘探局、哥伦比亚国家地质勘探局、哥伦比亚国家地质勘探局、哥伦比亚国家地质勘探局、哥伦比亚国家地质勘探局。Con base en la profunddad de la sismicidad, la proximidad geográfica y el contexto tectónico，通过确定各自的张量，对30个区域进行了划分。洛杉矶resultados revelan,洛杉矶方案compresivos dominan al norte de Los 5°N在el esfuerzo水平maximo (SHmax)这种orientacion -, controlada关于convergencia之间el Bloque Panama-Choco y el Bloque Norandino。在此基础上，我们提出了一种新的解决方案，即解决方案、解决方案、解决方案、解决方案和解决方案。A lo largo del frente de subducción de la Placa de Nazca, los regímenes extensionales pre-fosa evolsion and haacia configuracones compaciones postfosa dentro del prisma de acreción。在考卡省和布卡拉曼加省的两省建立了深厚的媒介关系，并在西北-东南两省建立了广泛的媒介关系，在加勒比地区建立了深厚的媒介关系，在加勒比地区建立了深厚的媒介关系。La distribución de los tensores de esfuerzo confirma que el límite centre los bloques Panamá-Chocó由Norandino es strucalmente complex， mientras que las cordilleras Oriental y Central exhien regímenes透明的de secgundo orden coherentes confallas corticales de gran escala。
{"title":"Stress regime of Colombia from seismological tensor inversion","authors":"Olga Bohórquez-Orozco , Jhon Restrepo-Berrío , Héctor Mora-Páez","doi":"10.1016/j.jsames.2025.105894","DOIUrl":"10.1016/j.jsames.2025.105894","url":null,"abstract":"<div><div>This study characterizes the present-day stress field of northwestern SouthAmerica using 337 focal mechanism solutions compiled from the Colombian Seismological Network, USGS, GEOFON, and GCMT catalogues. Based on seismicity depth, geographic proximity, and tectonic context, 30 stress regions were delineated, and their corresponding stress tensors were determined. The results reveal that compressional regimes dominate north of 5° N, where the maximum horizontal stress (SHmax) trends NW–SE, controlled by the convergence between the Panama–Choco Block and the North Andean Block. Southward, the regime transitions to strike-slip faulting with E–W-oriented SHmax, associated with right-lateral and conjugate fault systems. Along the Nazca Plate subduction front, pre-trench extensional regimes evolve into post-trench compressional settings within the accretionary prism. Intermediate-depth tensors in the Cauca and Bucaramanga sectors reveal an in-slab extensional axis for the former and NW–SE compression for the latter, where seismicity patterns support the presence of a detached Paleo-Caribbean slab. The stress tensor distribution confirms that the Panama–Choco–North Andean boundary is structurally complex, while the Eastern and Central Cordilleras display second-order transpressive regimes consistent with major crustal-scale faults.</div></div><div><div>Este estudio caracteriza el campo de esfuerzos actual de la esquina noroccidental de Suramérica, utilizando 337 soluciones de mecanismos focales compiladas de los catálogos de la Red Sismológica Nacional de Colombia, USGS, GEOFON y GCMT. Con base en la profundidad de la sismicidad, la proximidad geográfica y el contexto tectónico, se delimitaron 30 regiones de esfuerzo y se determinaron sus respectivos tensores. Los resultados revelan que los regímenes compresivos dominan al norte de los 5° N, donde el esfuerzo horizontal máximo (SHmax) tiene una orientación NW–SE, controlada por la convergencia entre el Bloque Panamá–Chocó y el Bloque Norandino. Hacia el sur, el régimen transiciona a fallamiento de tipo transcurrente con SHmax orientado E–O, asociado a sistemas de fallas dextrales y conjugadas. A lo largo del frente de subducción de la Placa de Nazca, los regímenes extensionales pre-fosa evolucionan hacia configuraciones compresivas pos-fosa dentro del prisma de acreción. Los tensores de profundidad intermedia en los sectores de Cauca y Bucaramanga revelan un eje extensional dentro de la losa para el primero y compresión NW–SE para el segundo, donde los patrones de sismicidad respaldan la presencia de una paleolosa Caribe desprendida. La distribución de los tensores de esfuerzo confirma que el límite entre los bloques Panamá–Chocó y Norandino es estructuralmente complejo, mientras que las cordilleras Oriental y Central exhiben regímenes transpresivos de segundo orden coherentes con fallas corticales de gran escala.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105894"},"PeriodicalIF":1.5,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694507","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}
Pub Date : 2025-12-02DOI: 10.1016/j.jsames.2025.105893
Maria Liceth Cabrera Ruiz, Alessandro Batezelli
<div><div>Understanding carbonate rocks and their geomechanical behavior is essential for optimizing hydrocarbon production. In carbonate reservoir, defining geomechanical facies offers an innovative approach to predict mechanical heterogeneity and supporting hydraulic fracturing design at the field scale. This study aims to classify the Barra Velha Formation into geomechanical facies by integrating mechanical analysis with rock characterization, in order to evaluate how mechanical strength, rock type, diagenetic processes influence the brittleness index and, consequently, reservoir integrity and development. This study utilized a comprehensive database from the Búzios Oil field, including conventional logs, image logs, leak-off tests, repeat formation tests, nuclear magnetic resonance data, mineral spectroscopy, X-ray diffraction, thin section and core photographs, and seismic data. The geomechanical models were developed using dynamic geomechanics and calibrated with well-test data. In addition, a Bayesian classification technique was used to define geomechanical facies. Carbonate rocks were classified according to Gomes et al. (2020). The in-situ stress distribution indicates that the current stress regime in the field is dual, ranging between normal and strike-slip, with a pore pressure gradient greater than the hydrostatic one. The maximum horizontal stress azimuth has two predominant orientations, approximately 80° and 270°. This orientation shows variations compared to the paleo-stress directions, which were aligned with the regional tectonic framework. Four geomechanical facies were defined, with mechanical strength ranging from intermediate to very low (Compacted, Brittle-Reservoir, Ductile-Sealing, and Semiductile-Reservoir), and an overall classification accuracy of 82 %. Compacted facies exhibit the highest mechanical strength and have a high content of quartz, feldspar, and mica due to grainstone texture with a high degree of cementation, very low porosity, and nearly zero permeability. In contrast, Semiductile-Reservoir facies, which displays the lowest mechanical strength, has the highest weight fraction of carbonate and is dominated by in-situ rocks, such as spherulitestones, these exhibit the best porosity and permeability properties, evidence of dissolution processes, and low cementation. Conversely, Ductile-Sealing facies present higher clay fraction values, microporosity, and stylolite development, which coincide with Mudstone lithologies. Regarding brittleness analysis, Compacted facies showed a higher propensity to develop drilling-induced tensile fractures and had the highest IB values. On the other hand, Ductile-Sealing facies were more prone to the development of breakouts, while Semiductile-Reservoir was prone to low amplitude fractures associated with the lowest IB values. In conclusion, this geomechanical study has provided valuable insights into the influence of diagenetic overprinting processes on carbonate rocks, wh
了解碳酸盐岩及其地质力学行为对于优化油气产量至关重要。在碳酸盐岩储层中，定义地质力学相提供了一种创新的方法来预测力学非均质性，并支持现场规模的水力压裂设计。本研究旨在将力学分析与岩石表征相结合，将Barra Velha组划分为地质力学相，以评价力学强度、岩石类型、成岩作用对脆性指数的影响，从而影响储层的完整性和发育程度。该研究利用了Búzios油田的综合数据库，包括常规测井、图像测井、泄漏测试、重复地层测试、核磁共振数据、矿物光谱、x射线衍射、薄片和岩心照片以及地震数据。利用动态地质力学建立地质力学模型，并根据试井数据进行校准。此外，采用贝叶斯分类技术定义地质力学相。碳酸盐岩分类依据Gomes et al.（2020）。地应力分布表明，当前现场应力场为正滑与走滑双重应力场，孔隙压力梯度大于静水压力梯度。最大水平应力方位有两个主要方向，约为80°和270°。与与区域构造格架一致的古应力方向相比，这一方向表现出变化。定义了四种地质力学相，其机械强度从中等到极低（压实相、脆性储层相、延性密封相和半延性储层相），总体分类精度为82%。压实相由于胶结程度高、孔隙度极低、渗透率接近于零的颗粒岩结构，机械强度最高，石英、长石、云母含量高。半枝储层相力学强度最低，碳酸盐岩质量分数最高，以球晶岩等原生岩为主，具有最佳的孔隙度和渗透率，具有溶蚀作用的证据，胶结作用较弱。相反，延性封闭相具有较高的粘土分数值、微孔隙度和柱面岩发育，与泥岩岩性一致。在脆性分析方面，致密相更倾向于形成钻井诱发的张性裂缝，其IB值最高。另一方面，延性—封闭性相更容易发育裂缝，而半延性—储层更容易发育低幅度裂缝，且IB值最低。综上所述，该地质力学研究为研究成岩叠印作用对碳酸盐岩的影响提供了有价值的见解，碳酸盐岩受沉积构造控制。这些因素共同决定了岩石的力学行为。四种地质力学相的地震反演预可行性分析强调了在油田规模上应用这种分类的潜力，从而能够更准确地描述储层特征。这些发现不仅适用于巴西盐下储层，也适用于全球其他具有类似沉积和成岩历史的碳酸盐岩储层。
{"title":"Integrated analysis of geomechanical facies and diagenetic controls on brittleness and reservoir quality in pre-salt carbonates","authors":"Maria Liceth Cabrera Ruiz, Alessandro Batezelli","doi":"10.1016/j.jsames.2025.105893","DOIUrl":"10.1016/j.jsames.2025.105893","url":null,"abstract":"<div><div>Understanding carbonate rocks and their geomechanical behavior is essential for optimizing hydrocarbon production. In carbonate reservoir, defining geomechanical facies offers an innovative approach to predict mechanical heterogeneity and supporting hydraulic fracturing design at the field scale. This study aims to classify the Barra Velha Formation into geomechanical facies by integrating mechanical analysis with rock characterization, in order to evaluate how mechanical strength, rock type, diagenetic processes influence the brittleness index and, consequently, reservoir integrity and development. This study utilized a comprehensive database from the Búzios Oil field, including conventional logs, image logs, leak-off tests, repeat formation tests, nuclear magnetic resonance data, mineral spectroscopy, X-ray diffraction, thin section and core photographs, and seismic data. The geomechanical models were developed using dynamic geomechanics and calibrated with well-test data. In addition, a Bayesian classification technique was used to define geomechanical facies. Carbonate rocks were classified according to Gomes et al. (2020). The in-situ stress distribution indicates that the current stress regime in the field is dual, ranging between normal and strike-slip, with a pore pressure gradient greater than the hydrostatic one. The maximum horizontal stress azimuth has two predominant orientations, approximately 80° and 270°. This orientation shows variations compared to the paleo-stress directions, which were aligned with the regional tectonic framework. Four geomechanical facies were defined, with mechanical strength ranging from intermediate to very low (Compacted, Brittle-Reservoir, Ductile-Sealing, and Semiductile-Reservoir), and an overall classification accuracy of 82 %. Compacted facies exhibit the highest mechanical strength and have a high content of quartz, feldspar, and mica due to grainstone texture with a high degree of cementation, very low porosity, and nearly zero permeability. In contrast, Semiductile-Reservoir facies, which displays the lowest mechanical strength, has the highest weight fraction of carbonate and is dominated by in-situ rocks, such as spherulitestones, these exhibit the best porosity and permeability properties, evidence of dissolution processes, and low cementation. Conversely, Ductile-Sealing facies present higher clay fraction values, microporosity, and stylolite development, which coincide with Mudstone lithologies. Regarding brittleness analysis, Compacted facies showed a higher propensity to develop drilling-induced tensile fractures and had the highest IB values. On the other hand, Ductile-Sealing facies were more prone to the development of breakouts, while Semiductile-Reservoir was prone to low amplitude fractures associated with the lowest IB values. In conclusion, this geomechanical study has provided valuable insights into the influence of diagenetic overprinting processes on carbonate rocks, wh","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105893"},"PeriodicalIF":1.5,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694505","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}
Pub Date : 2025-12-02DOI: 10.1016/j.jsames.2025.105897
Pedro Victor F. de S. Alves , Nilson F. Botelho , Valmir da S. Souza , Lys M. Cunha
The Rosa de Maio deposit is a magmatic-hydrothermal gold deposit located in the northwestern Tapajós Mineral Province, within the south-central Amazonian Craton, northern Brazil. It is genetically linked to the Rosa de Maio Granite (ca. 1890 Ma), a high-K calc-alkaline and relatively oxidized intrusion associated with the late-to post-collisional continental arc magmatism of the Parauari Suite (1.89–1.87 Ga). Although the magmatic evolution of the deposit has recently been addressed, its hydrothermal evolution has not yet been investigated in detail. This study proposes that the Rosa de Maio deposit comprises two genetically related hydrothermal systems: a deeper system characterized by sodic, potassic, propylitic, and sericitic alteration, and a shallower, near-surface system marked by sericitic alteration and the development of a quartz stockwork system. Gold mineralization occurs in both systems, hosted within sericitic alteration zones and sulfide-rich quartz veins. In all cases, gold shows a consistent spatial association with sulfides, particularly pyrite. Muscovite from a quartz vein in the shallower system yielded a40Ar/39Ar plateau age of 1808.3 ± 7.1 Ma, interpreted either as the result of isotopic resetting during a younger thermal event or as evidence of a younger mineralizing magmatism not yet identified in the area. Sulfur isotope analyses of pyrite from both systems yielded δ34S values between +0.5 and + 1.3 ‰, consistent with a dominantly magmatic sulfur source. Overall, the deeper system of the Rosa de Maio deposit shares several similarities with Au-rich porphyry-style deposits, whereas the shallower system likely represents a superimposed epithermal mineralization, now largely eroded.
Rosa de Maio金矿床是位于巴西北部亚马逊河克拉通中南部Tapajós矿产省西北部的岩浆热液型金矿床。它与Rosa de Maio花岗岩（约1890 Ma）有关，这是一种高钾钙碱性和相对氧化的岩体，与Parauari套件（1.89-1.87 Ga）碰撞后晚期的大陆弧岩浆活动有关。虽然该矿床的岩浆演化已在近期得到解决，但其热液演化尚未得到详细的研究。研究认为，Rosa de Maio矿床包括两个成因相关的热液系统：深层热液系统以钠质、钾质、丙质和绢云母蚀变为特征；浅层近地表热液系统以绢云母蚀变和石英网系统发育为特征。两个体系均有金矿成矿，赋存于绢云母蚀变带和富含硫化物的石英脉中。在所有情况下，金与硫化物，特别是黄铁矿表现出一致的空间联系。来自浅层石英脉的白云母的40ar /39Ar平台年龄为1808.3±7.1 Ma，这可能是较年轻热事件期间同位素重置的结果，也可能是该地区尚未发现的较年轻矿化岩浆活动的证据。两个体系黄铁矿的硫同位素分析结果显示，其δ34S值在+0.5 ~ + 1.3‰之间，与岩浆硫源一致。总的来说，Rosa de Maio矿床的深层系统与富金斑岩型矿床有几个相似之处，而浅层系统可能代表叠加的浅成热液矿化，现在大部分被侵蚀。
{"title":"Genesis of the Rosa de Maio gold deposit, Tapajós Mineral Province, northern Brazil: Hydrothermal evolution and mineralization from geochemistry, mineral chemistry, 40Ar/39Ar geochronology, and sulfur isotopes","authors":"Pedro Victor F. de S. Alves , Nilson F. Botelho , Valmir da S. Souza , Lys M. Cunha","doi":"10.1016/j.jsames.2025.105897","DOIUrl":"10.1016/j.jsames.2025.105897","url":null,"abstract":"<div><div>The Rosa de Maio deposit is a magmatic-hydrothermal gold deposit located in the northwestern Tapajós Mineral Province, within the south-central Amazonian Craton, northern Brazil. It is genetically linked to the Rosa de Maio Granite (<em>ca.</em> 1890 Ma), a high-K calc-alkaline and relatively oxidized intrusion associated with the late-to post-collisional continental arc magmatism of the Parauari Suite (1.89–1.87 Ga). Although the magmatic evolution of the deposit has recently been addressed, its hydrothermal evolution has not yet been investigated in detail. This study proposes that the Rosa de Maio deposit comprises two genetically related hydrothermal systems: a deeper system characterized by sodic, potassic, propylitic, and sericitic alteration, and a shallower, near-surface system marked by sericitic alteration and the development of a quartz stockwork system. Gold mineralization occurs in both systems, hosted within sericitic alteration zones and sulfide-rich quartz veins. In all cases, gold shows a consistent spatial association with sulfides, particularly pyrite. Muscovite from a quartz vein in the shallower system yielded a<sup>40</sup>Ar/<sup>39</sup>Ar plateau age of 1808.3 ± 7.1 Ma, interpreted either as the result of isotopic resetting during a younger thermal event or as evidence of a younger mineralizing magmatism not yet identified in the area. Sulfur isotope analyses of pyrite from both systems yielded δ<sup>34</sup>S values between +0.5 and + 1.3 ‰, consistent with a dominantly magmatic sulfur source. Overall, the deeper system of the Rosa de Maio deposit shares several similarities with Au-rich porphyry-style deposits, whereas the shallower system likely represents a superimposed epithermal mineralization, now largely eroded.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105897"},"PeriodicalIF":1.5,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694508","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}
Pub Date : 2025-12-01DOI: 10.1016/j.jsames.2025.105892
Augusto F. Morosini , Noelia B. Vilchez , Silvana L. Spagnotto , Andrés D. Richard , Marina K. Escobares , Melina A. Quiroga
The southwestern end of the Sierra de San Luis, located within the Argentinian Pampean flat-slab segment, presents a complex tectonic architecture associated with intraplate deformation in a broken foreland setting. In this study, we use vertical electrical soundings (VES) to investigate the subsurface features in a particular sector of this region, aiming to characterize the geometry and depth of sedimentary basins and the underlying crystalline basement. Twenty-six VES were acquired using a Wenner configuration, reaching up to 316 m in depth. The geoelectrical models reveal three main resistivity domains: a high-resistivity crystalline basement (>500 Ωm), a low-resistivity clastic unit (LRCU; <29 Ωm), and a high-resistivity clastic unit (HRCU; 80–300 Ωm). These resistivity patterns, supported by surface geology and stratigraphic data, allow for the delineation of major tectonic blocks and depocenters. The results highlight a markedly heterogeneous basement topography controlled by N-S reverse and NW-SE oblique extensional faults. Lateral variations in sediment thickness and fault geometries indicate significant control from inherited basement eopalezoic anisotropies, including ductile shear zones and magmatic fabrics. This study provides new geophysical evidence for the segmentation of the foreland in the Sierra de San Luis and underscores the importance of integrating electrical methods in regions affected by thick-skinned tectonics. The findings have implications for neotectonic activity, structural evolution, and groundwater dynamics in intraplate settings.
{"title":"Geoelectric study in the southwestern end of the Sierra de San Luis: Insights into the broken foreland in the Pampean flat-slab segment","authors":"Augusto F. Morosini , Noelia B. Vilchez , Silvana L. Spagnotto , Andrés D. Richard , Marina K. Escobares , Melina A. Quiroga","doi":"10.1016/j.jsames.2025.105892","DOIUrl":"10.1016/j.jsames.2025.105892","url":null,"abstract":"<div><div>The southwestern end of the Sierra de San Luis, located within the Argentinian Pampean flat-slab segment, presents a complex tectonic architecture associated with intraplate deformation in a broken foreland setting. In this study, we use vertical electrical soundings (VES) to investigate the subsurface features in a particular sector of this region, aiming to characterize the geometry and depth of sedimentary basins and the underlying crystalline basement. Twenty-six VES were acquired using a Wenner configuration, reaching up to 316 m in depth. The geoelectrical models reveal three main resistivity domains: a high-resistivity crystalline basement (>500 Ωm), a low-resistivity clastic unit (LRCU; <29 Ωm), and a high-resistivity clastic unit (HRCU; 80–300 Ωm). These resistivity patterns, supported by surface geology and stratigraphic data, allow for the delineation of major tectonic blocks and depocenters. The results highlight a markedly heterogeneous basement topography controlled by N-S reverse and NW-SE oblique extensional faults. Lateral variations in sediment thickness and fault geometries indicate significant control from inherited basement eopalezoic anisotropies, including ductile shear zones and magmatic fabrics. This study provides new geophysical evidence for the segmentation of the foreland in the Sierra de San Luis and underscores the importance of integrating electrical methods in regions affected by thick-skinned tectonics. The findings have implications for neotectonic activity, structural evolution, and groundwater dynamics in intraplate settings.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105892"},"PeriodicalIF":1.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694510","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}
Pub Date : 2025-11-29DOI: 10.1016/j.jsames.2025.105895
D. Legrand , M. Perton , M.G. Gómez-Vasconcelos , P. Larrea
Volcanoes can be described as falling somewhere a large spectrum ranging from polygenetic systems, which are constructed through multiple, long-lived eruptive phases, to monogenetic systems, which usually form during a single eruptive event. Within this context, several decades of observations on Earth have shown that close and strong tectonic earthquakes can precede large eruptions of polygenetic volcanoes. In contrast, only a few close and large earthquakes have been reported before the birth of new monogenetic volcanoes, since the latter are rare. Here, we describe the unusually high number of large tectonic earthquakes that preceded the birth of the Paricutin monogenetic volcano in Mexico in 1943. Thirteen large tectonic earthquakes occurred in the near field during the 20-year period spanning the decade before the birth of Paricutin to the end of its eruption, whereas only one earthquake occurred within ten years after the eruption ended. This clustering of large tectonic earthquakes in space and time before and during the eruption of Paricutin is unusual for this region of Mexico. The significant difference in the number of tectonic earthquakes before, during, and after the eruption strongly suggests that Paricutin's birth and growth are related to these earthquakes. They may have changed the stress tensor near Paricutin's location, facilitating magma to migrate towards the surface and sustaining Paricutin's eruption for nine years - an unusually long period for a monogenetic volcano. We propose that changes in static and quasi-static stress fields, resulting from local faults, local tectonics, and static displacement fields generated by near-field earthquakes, may have triggered and boosted the Paricutin's eruption. In addition, we suggest that the dynamic stress field generated by the waves emitted by earthquakes may have altered magma pathways towards the surface prior to and during the Paricutin's eruption.
{"title":"Unusual number of large tectonic earthquakes before and during the birth of the Paricutin monogenetic volcano. Did they trigger, maintain, and boost the volcanic long-lasting activity from 1943 to 1952?","authors":"D. Legrand , M. Perton , M.G. Gómez-Vasconcelos , P. Larrea","doi":"10.1016/j.jsames.2025.105895","DOIUrl":"10.1016/j.jsames.2025.105895","url":null,"abstract":"<div><div>Volcanoes can be described as falling somewhere a large spectrum ranging from polygenetic systems, which are constructed through multiple, long-lived eruptive phases, to monogenetic systems, which usually form during a single eruptive event. Within this context, several decades of observations on Earth have shown that close and strong tectonic earthquakes can precede large eruptions of polygenetic volcanoes. In contrast, only a few close and large earthquakes have been reported before the birth of new monogenetic volcanoes, since the latter are rare. Here, we describe the unusually high number of large tectonic earthquakes that preceded the birth of the Paricutin monogenetic volcano in Mexico in 1943. Thirteen large tectonic earthquakes occurred in the near field during the 20-year period spanning the decade before the birth of Paricutin to the end of its eruption, whereas only one earthquake occurred within ten years after the eruption ended. This clustering of large tectonic earthquakes in space and time before and during the eruption of Paricutin is unusual for this region of Mexico. The significant difference in the number of tectonic earthquakes before, during, and after the eruption strongly suggests that Paricutin's birth and growth are related to these earthquakes. They may have changed the stress tensor near Paricutin's location, facilitating magma to migrate towards the surface and sustaining Paricutin's eruption for nine years - an unusually long period for a monogenetic volcano. We propose that changes in static and quasi-static stress fields, resulting from local faults, local tectonics, and static displacement fields generated by near-field earthquakes, may have triggered and boosted the Paricutin's eruption. In addition, we suggest that the dynamic stress field generated by the waves emitted by earthquakes may have altered magma pathways towards the surface prior to and during the Paricutin's eruption.</div></div>","PeriodicalId":50047,"journal":{"name":"Journal of South American Earth Sciences","volume":"170 ","pages":"Article 105895"},"PeriodicalIF":1.5,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694506","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}
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