The hydrogeological characteristics of roto-translational slides in flysch are complex, due to the inherent anisotropy and heterogeneity of rock masses and related deposits. The paper deals with the hydrogeological characterization of a reactivated roto-translational slide affecting Cretaceous flysch rocks, located in the northern Apennines of Italy. Continuous monitoring of groundwater levels, in-situ permeability and pumping tests, hydrochemical and physical analyses and Uranine tracers were the adopted prospecting methods. In this research hydrological monitoring and investigation are summarized in order to define a hydrogeological conceptual model of the landslide source area. Results showed that two overlaying hydrogeological units exist at the slope scale: the first is unconfined, but highly compartmentalized, and hosted in the fractured and dismembered rock slide body. The second is confined and lays in the undisturbed flysch below the sliding surface. The groundwater level in the confined hydrogeological unit is twenty meters higher than the groundwater level in the uppermost one. Moreover, the groundwater chemistry characterization revealed a rising of deep fluids in the landslide area.

The interest on low‐temperature geothermal resources is progressively increasing since their renewability and widespread availability. Despite their frequency, these resources and their development have been only partially investigated. This paper unravels the major physical processes driving a low‐temperature geothermal resource in NE Italy (Euganean Geothermal System) through conceptual and numerical modeling. Dense fracturing associated to regional fault zones and a relay ramp enhances regional to local flow of thermal waters. Their rapid upwelling in the Euganean Geothermal Field is favored by open extensional fractures deforming the relay ramp. The water (65–86 °C) is intensively exploited for balneotherapy, rendering it a profitable resource. Three‐dimensional coupled flow and heat transport numerical simulations based on this conceptual model are performed. Despite the presence of a uniform basal heat flow, a thermal anomaly corresponding to field observations develops in the modeling domain reproducing the relay ramp. Intensive fracturing extending across a wide area and a slightly anomalous heat flow favors a local increase in convection that drives the upwelling of deep‐seated hot waters. The simulations corroborate and refine the conceptual model, revealing that water of up to 115 °C is likely to be found in the unexplored part of the thermal field. This study furthers knowledge on fault‐controlled low‐temperature geothermal resources where the geological setting could enhance local convection without anomalous heat flows, creating temperatures favorable for energy production. Conceptual and numerical modeling based on solid geological and hydrogeological reconstructions can offer a support tool for further detailed explorations of these prominent resources.

The point dilution test is a single-well technique for estimating horizontal flow velocity in the aquifer surrounding a well. The test is conducted by introducing a tracer into a well section and monitoring its decreasing concentration over time. When using a salt tracer, the method is easy and inexpensive. Traditionally, the horizontal Darcy velocity is calculated as a function of the rate of dilution and is based on the simple assumption that the decreasing tracer concentration is proportional both to the apparent velocity into the test section and to the Darcy velocity in the aquifer. In this article, an alternative approach to analyse the results of point dilution tests is proposed and verified using data acquired at a test site in the middle Venetian plain, northeast Italy. In this approach, the one-dimensional equilibrium advection–dispersion equation is inverted using the CXTFIT model to estimate the apparent velocity inside the test section. Analysis of the field data obtained by the two approaches shows good agreement between the methods and suggests that it is possible to use the equilibrium advection–dispersion equation to estimate apparent velocity over a wide range of velocities.

Knowledge of the hydraulic and geological properties of karst systems is particularly valuable to hydrogeologists because these systems represent an important source of potable water in many countries. However, the high heterogeneity that characterizes karst systems complicates the definition of karst hydrogeological properties, and their estimation involves complex and expensive techniques. In this study, a workflow for karst spring characterization was used to analyze two springs, Nanto spring and Mossano spring, located in the Berici Mountains (NE Italy). Based on the data derived from 4 years of continuous hourly monitoring of discharge, water temperature and specific electrical conductivity, a hydrogeological conceptual model for the monitored springs was proposed. Flow rate measurements, which combined recession curve, flow duration curve and autocorrelation function techniques, were used to evaluate the spring discharge variability. Changes in spring discharge can be related both to the degree of karstification/permeability and to the size of the karst aquifer. Moreover, combining monitored parameters and rainfall—analyzed by the cross-correlation function and VESPA (Vulnerability Estimator for Spring Protection Areas) index approach—permitted assessment of the spring response to recharge and the behavior of the drainage system. Although the responses to the recharge events were quite similar, the two springs showed some differences in terms of the degree of karstification. In fact, Mossano spring showed a more developed karst system than Nanto spring. Three systems (two karsts and one matrix/fractured) are outlined for Mossano spring, while two systems (one karst and one matrix/fractured) are outlined for Nanto spring. La connaissance des propriétés hydrauliques et géologiques des systèmes karstiques est. particulièrement utile pour les hydrogéologues, car ces systèmes constituent des ressources en eau importantes dans de nombreux pays. Cependant, la grande hétérogénéité qui caractérise les systèmes karstiques rend difficile la définition des propriétés hydrogéologiques, et leur estimation implique la mise en œuvre de techniques complexes et onéreuses. Dans cette étude, une méthode de travail pour la caractérisation des sources karstiques a été utilisée pour l’analyse de deux sources (sources Nanto et Mossano), localisées dans les Monts Berici (Nord-Est de l’Italie). Sur la base des données issues de quatre ans de suivi horaire des débits, de la température et de la conductivité électrique de l’eau, un modèle hydrogéologique conceptuel des sources suivies a été proposé. Les mesures de débits, qui combinent les courbes de récession, les courbes de durée d’écoulement et les techniques de fonction d’autocorrélation, ont été utilisées pour évaluer la variabilité du débit des sources. Les changements du débit des sources peuvent être corrélés à la fois au degré de karstification/perméabilité et à la taille du système karstique. De plus, la combinaison des paramètres de suivi avec les données de pluie (analysée avec la fonction de corrélation croisée et l’approche indicielle VESPA - Estimateur de Vulnérabilité pour les Aires de Protection des Sources) a permis d’évaluer la réponse des sources à la recharge et le comportement du système de drainage. Bien que les réponses aux événements de recharge soient quasi similaires, les deux sources présentent certaines différences en termes de degré de karstification. En fait, la source Mossano montre un système karstique plus développé que la source Nanto. Trois systèmes (deux karstiques et un matriciel/fracturé) sont mis en évidence pour la source Mossano, alors que deux systèmes (un karstique et un matriciel/fracturé) caractérisent la source Nanto. El conocimiento de las propiedades hidráulicas y geológicas de los sistemas kársticos es especialmente valioso para los hidrogeólogos, ya que estos sistemas representan una importante fuente de agua potable en muchos países. Sin embargo, la gran heterogeneidad que caracteriza a los sistemas kársticos complica la definición de sus propiedades hidrogeológicas, y su estimación implica técnicas complejas y costosas. En este estudio, se utilizó un flujo de trabajo para la caracterización de manantiales kársticos para analizar dos de ellos, el manantial de Nanto y el manantial de Mossano, situados en las montañas Berici (NE de Italia). Basado en los datos derivados de cuatro años de monitoreo horario continuo de la descarga, temperatura del agua y conductividad eléctrica específica, se propuso un modelo conceptual hidrogeológico para los manantiales monitoreados. Se utilizaron medidas de caudal, que combinaron la curva de recesión, la curva de duración del caudal y técnicas de función de autocorrelación, para evaluar la variabilidad de la descarga de los manantiales. Los cambios en la descarga de los manantiales pueden estar relacionados tanto con el grado de karstificación/permeabilidad como con el tamaño del acuífero kárstico. Además, la combinación de los parámetros monitoreados y la lluvia—analizados por la función de autocorrelación y el enfoque del índice VESPA (Vulnerability Estimator for Spring Protection Areas)—permitió la evaluación de la respuesta del manantial en la recarga y del comportamiento del sistema de drenaje. Aunque las respuestas a los eventos de recarga fueron bastante similares, los dos manantiales mostraron algunas diferencias en términos del grado de karstificación. De hecho, el manantial de Mossano mostró un sistema kárstico más desarrollado que el de Nanto. Tres sistemas (dos kársticos y uno de matriz/fracturado) se perfilan para el manantial Mossano, mientras que dos sistemas (uno kárstico y otro de matriz/fracturado) son descriptos para el manantial Nanto....