Air pollution exceedances are important air quality events for its associated effects on public health. Chemical transport models are frequently used for estimating pollution concentrations, especially in areas with limited monitoring capacity. Even though their performance may be improved by combining observations from different platforms through data assimilation, in Mexico these applications are limited, especially those aiming to assimilate chemical composition observations. In this study, surface observations of O3, CO and NO2 from the local monitoring network (RAMA) together with conventional global meteorological observations, were assimilated over the Mexico City Metropolitan Area (MCMA) using the WRFDA-Chem v4.5.2 assimilation system and the 3DVAR algorithm. The global observations were obtained in PREPBUFR format and consisted of upper-air and surface weather reports collected worldwide. The observations included pressure, temperature, dew point, wind speed and direction, from several platforms including surface, radiosondes, and aircraft reports. Two sets of experiments focusing on the impact of the chemical initial and boundary conditions were conducted. One experiment used default chemical initial and boundary conditions provided. In the experiment denoted by “default”, the WRF-Chem model was initialized through predetermined NALROM (NOAA Aeronomy Lab Regional Oxidant Model) ideal profiles that are included in the model. These profiles represent a northern-hemispheric, mid-latitude, relatively clean atmospheric composition and provide values for species such as O3, CO, NOx. (WRF-Chem user guide). The other experiment, denoted by “global”, the NALROM ideal profile was replaced with external chemical fields obtained from the global chemical transport model WACCM (Whole Atmosphere Community Climate Model). These fields provide spatially and temporally varying initial and boundary conditions that reflect realistic large-scale chemical distributions rather than a static climatology. Results showed that chemical data assimilation corrected pollutants concentrations. Regarding CO and NO2, differences between model results and observations were rather small, suggesting the need of tuning the background error covariance matrix parameters for these pollutants. However, for ozone, using global model outputs to initialize the model, tended to better represent regional maximum concentration, whilst using default conditions tended to better represent regional average concentration. However, both setups estimated similar daily ozone peaks. This suggests that using default chemical conditions cycled over a long period may optimize storage and computing resources.
En este estudio se llevó a cabo la investigación hidrogeofísica del acuífero de San Agustín Texcaltitlán, municipio de Tenancingo Estado de México, para determinar los parámetros intrínsecos como la porosidad (n) y la conductividad hidráulica vertical (Kv) por análisis granulométrico; se midió la variación del nivel del agua en norias y se determinó el espesor (h) de los estratos de la zona no saturada y saturada empleando el método del Sondeo Eléctrico Vertical (SEV) y el arreglo Schlumberger de resistividad eléctrica (ρ). El objetivo consistió en determinar y zonificar la vulnerabilidad intrínseca a la contaminación del agua subterránea por fuentes antropogénicas con el método AVI, que define la resistencia hidráulica (C) y la capacidad protectora del acuífero con el método ICE, a partir de la conductancia longitudinal unitaria (S), con el método geoeléctrico del SEV. Ambos métodos solo requieren de dos parámetros, la Kv y el espesor h de las capas que constituyen la zona no saturada (ZNS), respectivamente. Los datos de 20 SEV adquiridos se interpretaron con el programa de computadora iterativo Interpex IX1D. Los resultados obtenidos indican que la porosidad de la ZNS es de 0.36-0.40 y la conductividad hidráulica vertical de 6-15 m/d, obtenida con la fórmula empírica de Slitcher. De 20 SEV realizados, se detectaron de 5 a 7 capas para el sistema acuífero con valores de la resistividad de 10-3,600 ohm-m y espesores variables, que se utilizaron para calcular las variaciones de la resistencia hidráulica (C), dando valores de 0.4-6.0 (días) indicando baja a alta vulnerabilidad, la conductancia longitudinal (S) y la resistencia transversal (R), conocidos como parámetros de Dar Zarrouk, arrojaron valores de 0.2-6.0 (Ω-1), indicando baja a alta capacidad de protección, y de 1,000-26,000 (ohm-m2), indicando zonas de baja a alta capacidad de infiltración, respectivamente. Finalmente, se elaboró el modelo conceptual de funcionamiento hidrogeológico del sistema acuífero de Texcaltitlán.
The aim of this paper is to evaluate the vulnerability of groundwater to contamination by adapting aquifer vulnerability index (AVI) approach, based mainly on the hydraulic conductivity (K) of the aquifer and overburden layers' thickness (h). The technique of vertical electrical sounding (VES) with the configuration of Schlumberger was applied to model the Quaternary aquifer and its overburden layers in the Khanasseer Valley area in Northern Syria. According to AVI classification, 5.88% of the study area is hugely polluted, 67.00% highly polluted, 23.53% moderately polluted, and 2.94% lowly polluted. Several hydro-geoelectrical parameters which affect the Aquifer Vulnerability Index (AVI) (such as anisotropy (lambda) of the subsurface hydrogeological layers, thickness (hOverb), resistivity (rho Overb), hydraulic conductivity (K), and hydraulic resistance (C) of the protecting layers) are statistically analyzed. Different mutual empirical relationships between the above parameters are established through analyzing their statistical correlation matrix. The derived empirical relationships highlight the mutual hydrological processes and the lithological connectivity nature between the study Quaternary aquifer and its overlaying layers. The obtained results highlighted the importance of safeguarding groundwater resources, and outlined resource allocation to protect the aquifer zones, for decision-makers. This was the first time that AVI approach is applied in Syria, and can be consequently extended to other Syrian aquifers. AVI can be also applied worldwide to estimate the conditions dominating the aquifer's protectivity in semi-arid regions.
In order to investigate the particle size distribution pattern of atmospheric suspended particles in Tehran, simultaneous sampling was conducted at six stations located in the western (ST1 to ST3) and eastern (ST4 to ST6) halves of the city. Mass concentrations were measured across nine size fractions ranging from particles larger than 11 µm to those smaller than 0.4 µm. The results indicated that at the western stations, the highest mass concentrations were mainly observed in the coarser particle fractions (11-7 µm and ≥11 µm), with maximum values of 19.6 and 16.3 µg.m-3 recorded at ST2 and ST1, respectively. This pattern suggests the dominance of mechanical sources and road dust resuspension in the western part of the city. In contrast, the eastern half of Tehran exhibited an increasing trend in concentration within the finer fractions (less than 2.1 µm), with the highest value measured at ST6 in the <0.4 µm fraction (18.7 µg.m-3). Additionally, in the 0.7-0.4 µm and 2.1-1.1 µm ranges, eastern stations showed higher concentrations compared to the western stations. This shift in size distribution pattern-from coarse-particle dominance in the west to fine-particle dominance in the east-may be attributed to differences in land use, traffic density, combustion-related sources, as well as topographic conditions and prevailing wind patterns across Tehran. Overall, the findings indicate a greater contribution of combustion-related and secondary fine particles in the eastern half, whereas the western half appears to be more influenced by primary sources and coarse particle resuspension. These results highlight the importance of region-specific management strategies for effective control of particulate matter pollution in the megacity of Tehran.
The subsidence of the East Coast of Lake Maracaibo-COLM in Zulia state in Venezuela is a geological event of anthropic cause with almost a century of existence. We wanted to know the current state of this event with the use of the Interferometric Synthetic Aperture Radar-InSAR technique, for this, we emphasized the need to mitigate atmospheric delays in the data, for which the ERA5 climate model with PyAPS was applied. In order to obtain accurate subsidence measurements in three oil fields located in the COLM (Tia Juana, Lagunillas and Bachaquero), whose cumulative subsidence process is approximately 5 meters between 1926 and 1986. For this study, subsidence values were estimated, for the period from 2018 to 2020, using a dataset of 157 interferometric Sentinel-1 images (79 from ascending orbits and 78 from descending orbits), which allowed the calculation of the values of displacements along the line of sight-LOS for both orbits, the tropospheric delay contribution, and the east-west and vertical components values, extracted from representative pixels with high coherence and with spatial and temporal average, having random noise component reduced, obtaining displacement values for Tia Juana, Lagunillas and Bachaquero fields respectively of: -6.4 +/- 0.8 cm/y; -7.9 +/- 1.0 cm/y and; -7.1 +/- 0.8 cm/y, for ascending mode. From 1.2 +/- 0.5 cm/y; -4.1 +/- 0.5 cm/y and; -1.8 +/- 0.3 cm/y, for descending mode. Also, by selecting representative pixels, we estimated reliable values for contribution from tropospheric delay, obtaining: -0.2 cm/y and -0.6 cm/y; -0.3 cm/y and -0.5 cm/y and; -0.4 cm/y and -0.5 cm/y. And the east-west (dE) and vertical (dU) components for the three fields, with: -6.79 cm/y and -2.94 cm/y; -3.27 cm/y and -5.19 cm/y and; -5.92 cm/y and -6.29 cm/y respectively, minimizing the risk that geometric projection errors will amplify underlying noise.
Submarine channels are major components that transport and store sediments across the continental margins that act as confined pathways for turbidity currents, facilitating sediment transfer from the shallow to the deep ocean and forming important sand-rich deposits with high hydrocarbon reservoir potential. Sedimentary processes are crucial for sculpting submarine channel morphologies and the building blocks of their architectural elements. This could be understood by seismic geomorphology analysis, which reveals the geological and geomorphological features through seismic data. Understanding the submarine channels through their morphology and architecture will help to build detailed geometry and evolution for further application, such as reservoir prediction, hydrocarbon migration and geological carbon storage. This review evaluates the effectiveness of seismic attributes in characterizing submarine channel geomorphology. This study examines 20 peer-reviewed articles published between 2016 and 2023 that applied seismic attribute analyses for geological interpretation of submarine channels. Seismic attributes such as RMS (root-mean square), variance, instantaneous frequency, sweetness, dip, curvature, coherence, and envelope were commonly applied in the reviewed case studies. Physical attributes highlight amplitude-related variations that may reflect lithological contrasts, depending on data calibration and depositional context, while geometrical attributes delineate channel margins and planform geometries and are strongly dependent on seismic data quality. In cases where single attributes are insufficient to clearly reveal channel geomorphology, additional analyses such as co-rendering and spectral decomposition were employed to enhance interpretation. This study confirms that seismic attributes provide reliable insights into submarine channel deposits, including possible lithological contrasts, channel boundaries, channel-belt morphology, and the distribution of sediment accumulations within channel systems. However, the accuracy of interpretation depends on seismic data quality and the geological understanding of the study area. Inadequate knowledge or poor-quality seismic data can lead to misapplication of attribute parameters and potential misinterpretation.
Critical radius (Rc ) determination in porous media is essential for permeability estimation through analytical models. This study presents the first systematic comparison of the Euler-Poincaré Characteristic (EPC) method and queue-based Invasion Percolation (QBIP) algorithm using four synthetic porous structures (SPS) with controlled geometry and topology to determine Rc . QBIP demonstrated universal applicability, determining Rc = 0.09 – 0.15 μm across all SPS. EPC required negative initial connectivity for its application; positive values prevented zero-crossing identification, and while the derivative criterion detected pore size distribution (PSD) transitions, these do not correspond to percolation thresholds in disconnected structures. Deviations from design modal radii ranged from 0 – 70% for EPC and 6.7 – 50% for QBIP; no single criterion was uniformly superior. Despite morphological operations altering the initial PSD to accomplish the target porosity in SPS generation, both methods identified Rc within the same order of magnitude as the design modes (0.10 – 0.15 μm). These findings demonstrate that EPC and QBIP provide complementary insights: EPC reveals topological transitions while QBIP captures invasion physics, enabling geometric, topological, and capillary characterization of porous media. This dual-method approach provides quantitative criteria for the selection of the method based on sample connectivity and enables cross-validation to reduce uncertainty in Rc determination for use in analytical permeability models.
En este trabajo se presentan los resultados de un Play Fairway Analysis realizado en la zona geotérmica localizada dentro del Complejo Caldera de Acoculco. En este estudio, considerando la existencia probada de una anomalía geotérmica en el subsuelo (identificada con pozos de >1.5 km de profundidad), se han utilizado datos geocientíficos de estudios previos considerados como indicadores o proxies de permeabilidad para generar el modelo de favorabilidad geotérmica. Este Play Fairway Analysis tiene un enfoque de expertos (expert-driven), debido a que no existen pozos con recursos geotérmicos probados para realizar un Play Fairway Analysis basado en datos (data-driven). Los datos empleados en este análisis fueron la ubicación de las fallas, del flujo de CO2, de los manantiales, de la temperatura del suelo, de los depósitos de ópalo y de los cráteres de erupciones hidrotermales. Las capas de los datos (evidence layers) fueron manejadas e integradas usando el software QGIS®. Los resultados muestran dos zonas con mayor favorabilidad geotérmica, ubicadas a aproximadamente 200 m al noroeste del pozo exploratorio EAC-1 y en la zona conocida como Alcaparrosa. En este trabajo, gracias a la recopilación de datos, también se discute por qué la zona geotérmica de Acoculco podría ser un sistema geotérmico convectivo y cómo las zonas con mayor favorabilidad geotérmica resultantes son las que tienen mayor potencial para alojar fluidos geotérmicos.
This study presents an innovative weighted fuzzy soft set-based multi-criteria decision-making model (B-model) for evaluating groundwater quality and identifying contamination sources in urban settings, with a case study in Agartala, Tripura, North-East India. Rapid urbanization and anthropogenic pressures have significantly impacted groundwater quality, demanding advanced methodologies for effective assessment and management. The proposed model incorporates ten critical groundwater quality parameters (GWQP—pH, electrical conductivity, iron concentration, dissolved oxygen, total hardness, total alkalinity, total dissolved solids, calcium, magnesium, and turbidity), transformed into fuzzy soft sets for comprehensive analysis. Groundwater samples were systematically collected from ten strategic locations across Agartala Municipal Corporation during three distinct seasons: pre-monsoon (March–May), monsoon (June–September), and post-monsoon (October–November) of 2023–2024. The analysis revealed seasonal variations in groundwater quality, with notable degradation during the pre-monsoon season due to reduced aquifer recharge and increased evaporation, while monsoon improvements were limited, primarily influenced by rainfall dilution. Specific areas consistently exhibited high pollution levels, highlighting localized contamination sources and elevated health risks. The model’s weighted pollution scores enabled precise identification of pollution sources, facilitating targeted intervention strategies. This research underscores the potential of fuzzy soft set-based approaches for robust groundwater quality assessment and emphasizes their integration into sustainable water management practices and urban planning to mitigate contamination risks in rapidly urbanizing regions like Agartala. Comparative analyses with existing methods validate and underscore the advantages of our approach.
La definición de los parámetros de diseño sismorresistente de todo tipo de infraestructura resulta crucial para asegurar un buen desempeño en países ubicados en zonas con amenaza sísmica significativa. El objetivo principal de los códigos o normas que rigen el diseño sismorresistente es la protección de la vida; sin embargo, la definición del coeficiente de diseño (cs), que determina la resistencia a carga lateral de una estructura ante acciones sísmicas, tiene además un impacto económico y social, debido al costo de construcción y a las pérdidas futuras esperadas. La amenaza sísmica se centra en el estudio de la intensidad sísmica esperaba (PGA, PGV, entre otros), y su recurrencia, mientras que el riesgo sísmico se relaciona con el estudio de los impactos generados debido a las acciones sísmicas sobre un único elemento o un portafolio de elementos expuestos, usualmente expresado con diferentes métricas, como probabilidad de colapso, número de fatalidades y pérdidas económicas. En este contexto, la definición de cs, a menudo representada en espectros de diseño paramétrico, debería incluir un análisis tanto de amenaza como riesgo que permita integrar diferentes métricas como la probabilidad de excedencia, la probabilidad de colapso o las pérdidas futuras esperadas. En este trabajo se exploran las metodologías más aceptadas a nivel mundial para la definición de cs en normas sismorresistentes y se propone el uso de su envolvente, justificando que el beneficio en términos de seguridad de colapso es mucho mayor que el impacto en el costo total esperado a lo largo de la vida útil. Para ello, se tomó como caso de estudio a Colombia, un país que cuenta con diversos estudios de amenaza y riesgo sísmico, códigos de diseño e información disponible de manera abierta y libre.
The 1998-2017 unrest at Volc & aacute;n de Colima, M & eacute;xico showed a variety in destruction of andesitic lava domes that were formed during seven episodes of the lava-dome eruption. The destructions of the lava domes during six eruptive episodes (1 to 5 and 7) were realized with a sequence of Vulcanian explosions. Another type of destruction of the lava dome, because of a partial collapse of the southern sector of the crater, was recorded during episode 6. This study is based on the seismic signals and video images of destructive events, which were recorded by the networks of Colima University, and demonstrated regularity in the general process of this 20-year eruption. The explosive destruction of the lava domes was studied according to the two-phase conceptual model of explosive process proposed by Zobin et al. (2006a). There were estimated values of durations of the initial phase of the seismic signal, D = t2 - t1, proportional to the length of the way of the magma bubbles from the fragmentation level in the conduit to the surface, where the explosion occurring, and the energy of explosions, E. The temporal variations of these two parameters from episode to episode (in the case of episode 6 with collapse of the lava dome without large destructive Vulcanian explosion, E and D were taken equal to 0) allowed to recognize three destructive periods in development of the eruption. The change in the depth of the feeding magma reservoir was proposed as the decisive element in the change of process of the lava dome destruction. It allows to reconstruct the development of the 1998-2017 eruptive activity as a turbulence of magma deposit with its consumption with every episode of lava dome destruction.
This study presents an integrated analysis of ground subsidence and earthquake-induced settlements in Mexico City using Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques applied to Sentinel-1 satellite imagery. Subsidence in the Valley of Mexico-primarily caused by groundwater overexploitation-has historically led to significant structural damage across the urban landscape. While conventional monitoring methods such as benchmark leveling are effective, they are time- and resource-intensive. In this work, open-access Sentinel-1 data and the SNAP toolbox developed by the European Space Agency (ESA) were used to assess regional subsidence throughout 2016 and to identify sudden displacements linked to the September 2017 seismic events. Satellite-derived measurements were validated against historical benchmark data. The results demonstrate that DInSAR reliably captures both gradual subsidence patterns and abrupt, earthquake-related settlements, notably in the Historic Center and the vicinity of the Xico Volcano. Annual subsidence rates reached up to 0.45 m in some areas, while earthquake-induced deformations ranged from 0.01 to a 0.05 m. These findings highlight the effectiveness of satellite-based remote sensing as a cost-efficient and robust tool for ground subsidence monitoring in urban environments.
The study area is in the Central Tauride section of the Taurides, a tectonic unit in Turkey. This region encompasses the village of Akkaya (Feke-Adana) along with the surrounding areas of Adana province. The region has experienced polyphase deformation, resulting in faults and fractures that provide suitable locations for mineralization. Additionally, magmatism has contributed to the formation of various mineral deposits. Among these minerals is fluorite, which is extensively utilised in the metal, chemical, and glass industries. This study aims to investigate fluorite mineralization and the distribution of rare earth elements (REE) using the Inverse Distance Weighting (IDW) method, as well as assess the relationship between satellite-based tectonic lines and mineralization. The findings suggest that vein-type fluorite mineralization and the distribution of rare earth elements are generally aligned with the identified tectonic lineaments.
The present study reviews the subsurface distribution and geometry of clay-rich strata within the Oligo-Miocene & Ccedil;ukur & ccedil;e & scedil;me Formation in the & Scedil;ile area (Istanbul) using an integrated methodology combining Vertical Electrical Sounding (VES) and Ground Penetrating Radar (GPR). A total of 30 VES measurements were obtained and analyzed by 1D inversion, and the resultant models were assembled into 2D pseudosections to designate laterally continuous conductive layers. Low-resistivity zones seen across the profiles were interpreted as clay-dominant, aquiferous strata based on their distinctive electrical response and field observations. GPR data acquired with a 38-50 MHz antenna yielded high-resolution insights into the near-surface strata. Radargrams displayed continuous, moderately inclined reflectors indicative of the upper margins of clayey strata; however, signal attenuation restricted imaging at deeper levels. The integration of VES-derived resistivity structure with GPR reflections improved the interpretation of the clay layer's geometry and revealed thickness variations throughout the study area. The aggregated findings demonstrate that clay-rich strata often occur at depths of approximately 5 to 40 meters, with localized thickening influenced by structural and depositional factors. The concordance between VES and GPR interpretations enhances the credibility of the subsurface model generated in this work. This study demonstrates the efficacy of combining VES and GPR techniques to characterize diverse near-surface formations in regions where clay predominates, thereby influencing electrical and electromagnetic responses. The results establish a geophysical framework for subsurface characterization in analogous geological contexts and facilitate future research to enhance the stratigraphic and structural understanding of the & Ccedil;ukur & ccedil;e & scedil;me Formation.
We used geomagnetic and 2D induced polarization (IP) methods to identify potential gold mineralization zones in the Sangon-II Kolonprogo area, Yogyakarta. Historical geological data indicate that gold mineralization is associated with quartz veins. Magnetic field measurements at 200 points and 8 IP lines were taken in the study area. The results of the Reduction to Pole (RTP) analysis of magnetic data and IP inversion modeling show how the mineralized areas are distributed. Low magnetic anomaly values (<500 nT), medium (500-1000 nT), and high values (>1000 nT) are interpreted as high, medium, and low alteration zones, respectively. By combining resistivity and chargeability values, the IP inversion results show the zoning of mineralized areas in the Sangon-II area. Low resistivity (<50 Omega m) to medium (50-300 Omega m) and high chargeability (>30ms) are zones of saturated water layers, soil on the surface of the weathering of igneous rocks. Resistivity (50-300 Omega m) and medium chargeability (10-30 ms) are alteration zones of silica-clay, argillic, and propylitic. Medium resistivity (50-300) Omega m and high chargeability (>30 ms) are sulfide mineralization zones. High resistivity (> 300 Omega m) and low chargeability resistivity (> 300 Omega m) and high chargeability (> 30 ms) are zones of igneous rock with high metal content as veins. The results of magnetic and IP analysis indicate the presence of a fault with the direction of N350E. This fault controls the alteration process and sulfide mineralization in the Sangon-II area. The distribution of mineralization areas is in the east, extending to the south, around the fault. The results of 3D modeling show that this area is quite promising.
High-resolution airborne geophysical datasets from part of the southwestern Sokoto basin, northwestern Nigeria, were utilized to characterize lithological units and map their geometrical extent. The major lithological features interpreted from Landsat 8 Operational Land Imager (OLI) images and total magnetic intensity data facilitate the identification of variations in minerals and lithological units, including quartz, biotite gneiss, biotite granite, feldspathic sandstone, sandstone, ironstone, granite gneiss, and migmatite. The radiometric ternary map displayed geologic features quite similar to those on the Landsat 8, magnetic, and geological maps of the study area. 3D Euler deconvolution corroborated the SOURCE PARAMETER IMAGING (SPI) for estimated depth to concealed magnetic sources range within ≤ 200 m, 317.7 m to 500 m, and above 780 m, for shallow to intermediate and deeper depths, respectively. Euler solutions for the structural index (SI) of 0 and 1 revealed a perfect cluster along notable geologic features such as faults, shear zones, and lithological boundaries, mapped using the OLI multispectral band, lateral lithological boundaries, and the vertical geometry of the geologic formation within the southwestern part of the Sokoto basin. The research highlighted the advantages of utilizing airborne and multispectral datasets to achieve a more comprehensive characterization of the lithological units exposed at the surface.
The region of Zimapán, Hidalgo, situated within the Tolimán watershed, faces groundwater contamination issues due to high concentrations of arsenic (As) and, in certain sites, fluoride (F-). This pollution is associated with the presence of several mineral deposits enriched with metallic sulfides, such as pyrite and arsenopyrite, as well as other minerals such as scorodite, a mineral produced by an exothermic process that releases sulfate. The origin of this mineralization stems from two distinct mineralization events: the initial event, linked with intrusions, and the subsequent event, characterized as hydrothermal in nature. These post-tectonic events, together with the Laramide orogeny, have generated an abrupt geomorphology and deformation, mainly in the carbonate sequence, which is covered by volcanic sediments. This makes it difficult to characterize geological structures that are continuous at depth and that may influence the aquifer system and the contamination of the basin. This study aims to identify and analyze the geological formations potentially associated with the occurrence of arsenic in groundwater at specific locations that influence groundwater dynamics, as well as structural formations that act as sources and pathways for the transport of these solutes. In pursuit of this objective, various methods were employed to regionally characterize and infer subsurface structures. Magnetic anomaly and Bouguer anomaly data were utilized. Utilizing this information, indirect 3D three-dimensional models of the study area were constructed, which were linked to the geological formations prevalent in the area through a thorough analysis of gravimetric and aeromagnetic anomalies. Among the most relevant results obtained, we observed the presence of highly dense bodies associated with granitic intrusions. Additionally, certain lineaments were identified that align with NW-SE geological faults validated in previous works with other methodologies, which link the mineralization resulting from the granitic intrusions and enrich groundwater with highly toxic metals and metalloids, mainly with arsenic. Finally, hydrogeochemistry proved to be useful in evaluating the influence relationship between the main anomalous bodies and natural groundwater contamination.
Remote Sensing provides valuable information about objects or remote areas, either using active sensors (i.e. RADAR and LiDAR) or passive (i.e. multispectral or hyperspectral imagery) using satellite retrieved images. Quality of remote sensing satellite images is frequently degraded due to several reasons, in par-ticular earth atmosphere. Satellite imagery atmospheric correction (AC) is an active research area in the remote sensing community, the goal of this pre-processing method is to retrieve the surface reflectance (i.e. land or water) from the at-satellite radiance, usually obtained as raw binary numbers or digital numbers. Every image taken by satellite sensors is affected by atmospheric effects (i.e. scattering and absorption), so it is necessary to compensate or considering these effects to be able to remove them from the image before proceeding to extract useful characteristics from the image itself in a second feature extraction stage. This article provides a review of some of the most used Atmospheric Correction methods currently available from the simplest ones such as image-based methods to the state-of-the-art methods, based on complex Radiative Transfer Models, described in the literature to provide an entry point for engineers, practitioners and researchers interested on Remote Sensing from satellite imagery.
The Indus River Basin has undergone significant hydrological changes due to climate change, leading to increased flood frequency, posing a risk to agriculture-based food security. This study focused on rain-induced flood events from August to September 2022 across the provinces of Punjab, Sindh, and Baluchistan using Google Earth Engine, Sentinel-1A Synthetic Aperture Radar (SAR) data, and Landcover datasets. Flooding caused considerable damage to agricultural land and communities, affecting 49,602.92 km2 of land. In Sindh, the total land inundated is 2,042.1 km2 with 915.9 km2 of agricultural land and 609.8 km2 of built-up areas affected. Hence, district-level damage assessment includes Sukkur (497.1 km2), Sanghar (565.2 km2), and Khairpur (979.9 km2). In Baluchistan province, the flooded area was 10,733.4 km2. The agricultural land affected was 674.8 km2, and 47.8 km2 of built-up land. Heavy rain further intensified flooding affected 1002.2 km2 in Jhal Magsi, 7,266.5 km2 in Khuzdar, and 2,464.7 km2 in Lasbella. In Punjab, 4001.3 km2 of land flooded including 297.6 km2 of built-up areas, and 776.9 km2 affected agricultural land. At the District-level affected areas were D.G. Khan (1,871.3 km2), Muzaffargarh (620 km2), and Rajanpur (1,509.7 km2). integration of remote sensing and GEE provided crucial flood insights and climate risk reduction strategies, especially in data-scarce regions.
Geothermal energy, under a sustainability approach, constitutes a strategic alternative to replace the use of fossil fuels. However, its exploitation requires the application of rigorous environmental criteria to avoid generating negative ecological impacts that compromise its viability as a sustainable alternative. This study uses the Cerritos Colorados Geothermal Field (CGCC), located in the La Primavera Caldera, Jalisco, and developed in the 1980s, as a reference. The primary objective is to demonstrate the necessity of incorporating sustainability criteria at all stages of a geothermal power project's development, thereby preventing, reducing, and mitigating adverse environmental impacts and ensuring its sustainable, longterm use. To achieve this objective, a critical analysis methodology was used, analyzing and questioning the Environmental Impact Statement (EIS) used for the development of the geothermal field, while also assessing its relevance. The results of the Environmental Impact Assessment (EIA) analysis revealed significant inconsistencies in the application of national (and international) regulations, as well as the omission of numerous environmental impacts that were not reported during the field's development. The most important contribution of this work is the proposal of a sustainability framework for the CGCC (Central Geothermal Field) based on the concept and criteria of sustainable production. It is worth noting that this is a pioneering study in Mexico, aimed at promoting the sustainable use of geothermal energy in Protected Natural Areas, thereby contributing to extending the lifespan of geothermal fields within a sustainable framework.
