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The growth of the geothermal industry demands the constant search of techniques with the aim of reducing exploration efforts whilst minimizing subsurface uncertainty. The exploration of geothermal resources is fundamental from the exploitation point of view, especially in those regions where this energy is not as widespread as the rest of renewable sources. This research shows how geoelectrical methods can contribute to the investigation and characterization of medium–low enthalpy geothermal resources until about 800 m of depth. A 2000 m long electrical-resistivity tomography profile was performed in a region of Southern Spain with previous evidence of moderate geothermal potential. Results of this geophysical campaign (together with a preliminary geological characterization) allowed for the obtainment of a 2D profile and a pseudo-3D model with extensive information about the subsoil in terms of geological composition and formations. The interpretation of geophysical results denotes the existence of a potential formation constituted by carbonate materials with thickness greater than 300 m, crossing different fractures. Once the ideal location for the geothermal exploitation is defined, the research evaluates the contribution of the possible energy source, deducing that the energy extraction in the potential fracturing area would be double that of the one in the vicinity of the site.

In the contemporary era, the exploitation of aquifers in the agricultural sector has become increasingly important. In response, researchers have directed their efforts towards the formulation of effective methodologies, with geophysical prospecting emerging as a fundamental tool in locating the best underground deposits. The magnetic prospecting technique can discriminate between different categories of rocks, which facilitates the localisation of geological contacts—an essential factor in determining the strategic location of boreholes, while electromagnetic time-domain prospecting helps in the definition of sedimentary strata. In particular, this process reveals the important influence of tertiary and metamorphic formations on the regional hydrogeological framework of the studied area. The variable yields recorded in the wells in the area that have yielded good results are a clear indication of the presence of aquifers. However, it is important to note that numerous wells have been drilled in this region that have yielded negligible or even zero flow rates. Prudent selection of the location and depth of boreholes is essential to ensure proper management of this resource. The use of drones equipped with magnetometers is essential to speed up the spatial mapping process. Empirical results corroborate the accurate classification of lithological units, thus facilitating the selection of sites for groundwater abstraction. These studies serve to validate initial hypotheses and profoundly enrich our understanding of the hydrogeological dynamics of the site, thus providing avenues for optimal and sustainable exploitation and future academic research.

The objective of this study was to obtain the deep subsurface structure of a saline-evaporitic formation affected by an anticlinal structure, defining the position and thickness for its future exploitation (potassium salts). To improve this knowledge, geophysical methods can be applied to establish detailed information on geological structures at depth. This work analyzes the results of a deep time domain electromagnetic (TDEM) survey acquired over the southern flank of the Barbastro-Balaguer Anticline present in the Ebro Basin in the vicinity of Graus (Huesca, Spain), that controls the geometry of the Barbastro saline-evaporitic formation, of interest from the mining point of view. A deep time domain electromagnetic system (TDEM) is used, providing a penetration capability down to 3.0 km depth. A parametric constrained inversion over a lithological known borehole (Monzón-1) is used to obtain a resistivity model and then applied to the rest of the survey points. The applied methodology contributes to improving the geological knowledge, revealing a new detailed geological structure of the Barbastro saline-evaporitic formation affected by the Barbastro-Balaguer Anticline. The survey shows that the Barbastro saline-evaporitic formation presents a structure with a ramp hanging wall and close to flat footwall, generally dipping to the SW, with a decreasing thickness from 1103 m to 601 m, in concordance with the previous accepted geological structural model. The new geophysical study provides essential data, allowing design and drilling optimization in future mining exploitations.

The current energy context demands the use of environmentally friendly solutions that contribute to the displacement of traditional fossil fuels. In this regard, heat pumps have become an important tool in the decarbonization of the heating and cooling energy system. With the aim of providing new information in the field, this research is conducted to analyze the suitability of a Ground Source Heat Pump (GSHP) and an Air Source Heat Pump (ASHP) in two different scenarios. Systems are designed to cover the heating needs of a building placed in a cold climate area, characterized by being in a thermally and geologically favorable formation (Case 1), and in a mild climate location where the geology is not so appropriate for the thermal exchange with the ground (Case 2). Results highlight the need to perform an exhaustive study of the subsoil and the external conditions of the area for a reliable selection. In Case 1, the ASHP option is discarded due to the demanding outdoor air requirements that rocket the operating costs of the system. In Case 2, both solutions are viable, with the geothermal alternative preferred if the initial investment can be assumed, providing economic advantages from the 17th year of the system operation.

The need to use groundwater resources for agricultural and livestock farms is a constantly growing issue, as these resources condition the socio-economic development of many areas with limited climatic regimes and surface water resources. Decisions on the location and characteristics of groundwater extraction works are based on hydrogeological studies, in which geophysical techniques are a very useful tool. In our study, the Time-Domain Electromagnetics technique (TDEM) was used, which significantly improves the precision and safety when planning to drill for water extraction in Mesozoic formations thanks to the significant resistivity contrast among its different hydrogeological units. The performance of a research campaign using TDEM allows for obtaining 2D geoelectrical profiles which define the hydrogeological structure of the study area and the materials of which it is composed, enabling the selection of a site where drilling can be carried out with the best prospects of success. This article shows the usefulness of this study methodology, applied to Mesozoic formations in a specific area located in the municipality of Liceras (Soria, Spain).

The use of drones in mining and geological exploration is under rapid development, especially in the field of magnetic field prospection. In part, this is related to the advantages presented for over ground surveys, allowing for high-density data acquisition with low loss of resolution, while being particularly useful in scenarios where vegetation, topography, and access are limiting factors. This work analyzes results of a drone magnetic survey acquired across the old mines of Don Jacobo, where Copper-Cobalt-Nickel stratabound mineralizations were exploited in the Estancias mountain range of the Betic Cordillera, Spain. The survey carried out used a vapor magnetometer installed on a Matrice 600 Pro Hexacopter. Twenty-four parallel survey lines were flown with a speed of 5 m/s, orthogonal to the regional strike of the geological structure, and mineralization with 50 m line separation and 20 m flight height over the ground was studied. The interpretation of the magnetic data allows us to reveal and model two high magnetic susceptibility bodies with residual magnetization, close to the old mines and surface mineral shows. These bodies could be related to potential unexploited mineralized areas whose formation may be related to a normal fault placed to the south of the survey area. Our geophysical survey provides essential data to improve the geological and mining potential of the area, allowing to design future research activities.

The geothermal resources in Spain have been a source of deep research in recent years and are, in general, well-defined. However, there are some areas where the records from the National Institute for Geology and Mining show thermal activity from different sources despite no geothermal resources being registered there. This is the case of the area in the south of the Duero basin where this research was carried out. Seizing the opportunity of a deep borehole being drilled in the location, some geophysical resources were used to gather information about the geothermal properties of the area. The employed geophysical methods were time-domain electromagnetics (TDEM) and borehole logging; the first provided information about the depth of the bedrock and the general geological structure, whereas the second one gave more detail on the geological composition of the different layers and a temperature record across the whole sounding. The results allowed us to establish the geothermal gradient of the area and to discern the depth of the bedrock. Using the first 200 m of the borehole logging, the thermal conductivity of the ground for shallow geothermal systems was estimated.

For an automated camera focus, a fast and reliable algorithm is key to its success. It should work in a precisely defined way for as many cases as possible. However, there are many parameters which have to be fine-tuned for it to work exactly as intended. Most literature only focuses on the algorithm itself and tests it with simulations or renderings, but not in real settings. Trying to gather this data by manually placing objects in front of the camera is not feasible, as no human can perform one movement repeatedly in the same way, which makes an objective comparison impossible. We therefore used a small industrial robot with a set of over 250 combinations of movement, pattern, and zoom-states to conduct these tests. The benefit of this method was the objectivity of the data and the monitoring of the important thresholds. Our interest laid in the optimization of an existing algorithm, by showing its performance in as many benchmarks as possible. This included standard use cases and worst-case scenarios. To validate our method, we gathered data from a first run, adapted the algorithm, and conducted the tests again. The second run showed improved performance.