Browsing by Author "Daniele, Linda"

Now showing 1 - 6 of 6
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    Changes in the conceptual model of the Pampa del Tamarugal Aquifer : Implications for Central Depression water resources
    (2019) Viguier, Benoit; Daniele, Linda; Jourde, H.; Léonardi, Véronique; Yáñez Carrizo, Gonzalo Alejandro
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    Deciphering groundwater flow-paths in fault-controlled semiarid mountain front zones (Central Chile)
    (2021) Figueroa González, Ronny Javier; Viguier, Benoît; Taucare, Matías; Yañéz Carrizo, Gonzalo Alejandro; Arancibia Hernández, Gloria Cecilia; Sanhueza Soto, Jorge Luis; Daniele, Linda
    The Mountain-Block Recharge (MBR), also referred to as the hidden recharge, consists of groundwater inflows from the mountain block into adjacent alluvial aquifers. This is a significant recharge process in arid environments, but frequently discarded since it is imperceptible from the ground surface. In fault-controlled Mountain Front Zones (MFZs), the hydrogeological limit between the mountain-block and adjacent alluvial basins is complex and, consequently, the groundwater flow-paths reflect that setting. To cope with the typical low density of boreholes in MFZs hindering a proper assessment of MBR, a combined geoelectrical-gravity approach was proposed to decipher groundwater flow-paths in fault-controlled MFZs. The study took place in the semiarid Western Andean Front separating the Central Depression from the Principal Cordillera at the Aconcagua Basin (Central Chile). Our results, corroborated by field observations and compared with worldwide literature, indicate that: (i) The limit between the two domains consists of N-S-oriented faults with clay-rich core (several tens of meters width low electrical-resistivity subvertical bands) that impede the diffuse MBR. The "hidden recharge' along the Western Andean Front occurs through (ii) focused MBR processes by (ii.a) open and discrete basement faults (mass defect and springs) oblique to the MFZ that cross-cut the N-S-oriented faults, and (ii.b) high-hydraulic transmissivity alluvial corridors in canyons. Alluvial corridors host narrow unconfined mountain aquifers, which are recharged by indirect infiltration along ephemeral streams and focused inflows from oblique basement faults. This study also revealed seepage from irrigation canals highlighting their key role M the recharge of alluvial aquifers in the Central Depression. The proposed combined geophysical approach successfully incorporated (hydro)geological features and geophysical forward/inverse modelling into a robust hydrogeological conceptual model to decipher groundwater flow-paths in fault-controlled MFZs, even in the absence of direct observation points. (C) 2021 Elsevier B.V. All rights reserved.
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    Desalinización: oportunidades y desafíos para abordar la inseguridad hídrica en chile
    (Ministerio de Ciencia, Tecnología, Conocimiento e Innovación, 2022) Vicuña, Sebastián; Daniele, Linda; Farías, Laura; González, Humberto; Marquet, Pablo A.; Palma Behnke, Rodrigo; Stehr, Alejandra; Urquiza, Anahí; Wagemann, Elizabeth; Arenas Herrera, María J.; Bórquez, Rodrigo; Cornejo Ponce, Lorena; Delgado, Verónica; Etcheberry, Gabriel; Fragkou, María Christina; Fuster, Rodrigo; Gelcich, Stefan; Melo, Óscar; Monsalve, Tamara; Olivares, Marcelo; Ramajo, Laura; Ramírez Pascualli, Carlos; Rojas, Carolina; Rojas, Christian; Vilca Salinas, Patricia; Winckler, Patricio; Winckler, Patricio; Lambert, Fabrice
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    Effects of hydrogeochemistry on the microbial ecology of terrestrial hot springs
    (2023) Barbosa, Carla; Tamayo Leiva, Javier Alejandro; Alcorta Loyola, Jaime Andrés; Salgado Salgado, Oscar Alexis; Daniele, Linda; Morata, Diego; Diez Moreno, Beatriz
    Temperature, pH, and hydrochemistry of terrestrial hot springs play a critical role in shaping thermal microbial communities. However, the interactions of biotic and abiotic factors at this terrestrial-aquatic interface are still not well understood on a global scale, and the question of how underground events influence microbial communities remains open. To answer this, 11 new samples obtained from the El Tatio geothermal field were analyzed by 16S rRNA amplicon sequencing (V4 region), along with 191 samples from previous publications obtained from the Taupo Volcanic Zone, the Yellowstone Plateau Volcanic Field, and the Eastern Tibetan Plateau, with their temperature, pH, and major ion concentration. Microbial alpha diversity was lower in acid-sulfate waters, and no significant correlations were found with temperature. However, moderate correlations were observed between chemical parameters such as pH (mostly constrained to temperatures below 70°C), SO4 2− and abundances of members of the phyla Armatimonadota, Deinococcota, Chloroflexota, Campilobacterota, and Thermoplasmatota. pH and SO4 2− gradients were explained by phase separation of sulfur-rich hydrothermal fluids and oxidation of reduced sulfur in the steam phase, which were identified as key processes shaping these communities. Ordination and permutational analysis of variance showed that temperature, pH, and major element hydrochemistry explain only 24% of the microbial community structure. Therefore, most of the variance remained unexplained, suggesting that other environmental or biotic factors are also involved and highlighting the environmental complexity of the ecosystem and its great potential to test niche theory ecological associated questions.
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    Groundwater resources and recharge processes in the Western Andean Front of Central Chile
    (ELSEVIER, 2020) Taucare, Matias; Daniele, Linda; Viguier, Benoit; Vallejos, Angela; Arancibia, Gloria
    In Central Chile, the increment of withdrawals together with drought conditions has exposed the poor understanding of the regional hydrogeological system. In this study, we addressed theWestern Andean Front hydrogeology by hydrogeochemical and water stable isotope analyses of 23 springs, 10 boreholes, 5 rain-collectors and 5 leaching-rocks samples at Aconcagua Basin. From the upstream to the downstream parts of the Western Andean Front, most groundwater is HCO3-Ca and results from the dissolution of anorthite, labradorite and other silicate minerals. The Hierarchical Cluster Analysis groups the samples according to its position along the Western Andean Front and supports a clear correlation between the increasing groundwater mineralization (31-1188 mu S/cm) and residence time. Through Factorial Analysis, we point that Cl, NO3, Sr and Ba concentrations are related to agriculture practices in the Central Depression. After defining the regional meteoric water line at 33 degrees S in Chile, water isotopes demonstrate the role of rain and snowmelt above similar to 2000 m asl in the recharge of groundwater. Finally, we propose an original conceptual model applicable to the entire Central Chile. During dry periods, water releases fromhigh-elevation areas infiltrate in mid-mountain gullies feeding groundwater circulation in the fractured rocks of Western Andean Front. To the downstream, mountain-block and -front processes recharge the alluvial aquifers. Irrigation canals, conducting water from Principal Cordillera, play a significant role in the recharge of Central Depression aquifers. While groundwater in the Western Andean Front has a high-quality according to different water uses, intensive agriculture practices in the Central Depression cause an increment of hazardous elements for human-health in groundwater. (C) 2020 Elsevier B.V. All rights reserved.
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    Selective reactivation of inherited fault zones driven by stress field changes: Insights from structural and paleostress analysis of the Pocuro Fault Zone, Southern Central Andes (32.8 degrees S)
    (PERGAMON-ELSEVIER SCIENCE LTD, 2022) Taucare, Matias; Roquer, Tomas; Heuser, Gert; Perez-Estay, Nicolas; Arancibia, Gloria; Yanez, Gonzalo; Viguier, Benoit; Figueroa, Ronny; Morataa, Diego; Daniele, Linda
    This study aims to explain the selective reactivation of normal faults during the Andean orogeny at the Southern Central Andes western flank. We conducted a structural mapping and paleostress field reconstruction in the regional-scale Pocuro Fault Zone (PFZ) at 32.8 degrees S. Results reveal that the architecture of the PFZ results from at least two deformation phases, each revealing an individual progressive and gradual evolution. The earliest deformation phase is recorded by two similar to NS-striking normal faults involving a 5 km wide damage zone characterized by quartz-laumontite and calcite veins that were developed under an extensional regime with a WNW-ESE-trending sigma 3-axis. The latest deformation phase is recorded by one NS-striking reverse-dextral fault with goethite-hematite syn-tectonic precipitation and two NW-striking reverse-sinistral faults. Reverse faults were developed under a compressional/transpressional regime characterised by an ENE-WSW-trending sigma 1-axis with a sigma 2-/sigma 3-axis permutation. From a geophysical data reassessment, we inferred that observed faults in the surface within the PFZ are regional-scale deep-seated structures. Considering previous geochronological data, we correlated the earliest and latest phases with the Abanico Basin extension (middle Eocene-early Miocene) and its subsequent inversion (Miocene). Given the neotectonic evidence (geomorphic markers and deformation of unconsolidated deposits), the latter phase likely remains active. Quartz-laumontite cementation of the fault core's cataclastic material promotes mechanical strengthening leading to negative feedback for the reactivation of inherited normal faults as reverse ones. Conversely, the concentration of fractures in the damage zone between the normal faults promotes mechanical weakening resulting in a preferential area for the propagation of reverse fault during the compressive/transpressional phase.