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Copyright of Romanian Journal of Civil Engineering / Revista Română de Inginerie Civilă is the property of Matrix Rom and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The development of geothermal energy has received extensive attention because of global energy scarcity and environmental pollution. The Tangquan area is in the north of the Yangtze fold belt, and the lack of magmatic rock development has resulted in a low-temperature type of geothermal reservoir. There are sporadic hot springs and cold springs exposed in the study area, but the uncertain deep geological structure, unknown geothermal reservoir formation mechanism, and lack of detailed exploration data seriously restrict the exploration and development of geothermal resources in the area. Filling underground faults with water can significantly reduce electrical resistivity, while traps filled with warm water can cause a decrease in S-wave velocity. Thus, a new integrated geophysical method, including the controlled source audio-frequency magnetotelluric (CSAMT) and microtremor methods, is applied for geothermal exploration in the region. The combination of CSAMT and microtremor methods can determine thermal-controlled and water-conducting structures more effectively and locate geothermal storage more accurately. The source, channel, storage, and cover of regional geothermal reservoir formation are analyzed using geophysical and geological data. That is, the regional NE- and NW-trending faults are explained as thermal-controlled and water-conducted structures, respectively. The deep Sinian Dengying Formation supplies a heatand water-bearing space. The tectonic intersection area, especially the tensional fault zone, is found to be closely related to the existence of geothermal reservoirs, which is well verified by later drilling results. Finally, a geothermal reservoir model is established to comprehensively understand the distribution of geothermal energy in the region. [ABSTRACT FROM AUTHOR]

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Hainan Island is located in the northwestern South China Sea at the boundary of two tectonic plates. Surface features and actual drilling have confirmed that there are rich geothermal resources in the area, with predicted resources of 480 million GWh. On the basis of the 1:200,000 gravity and 1:10 aeromagnetic data and constrained by the well-explored Fushan Depression and Baocheng Rock Mass, we conducted a systematic study of hot dry rocks and evaluated the development potential of the geothermal resources of the medium-depth and deep hot dry rocks in Hainan Island for the first time. The island is structurally active, with extensive granites, strong volcanic and earthquake activities, and many hot springs, indicating that the geothermal geological conditions are favorable. There are two types of hot dry rocks, sedimentary basin type and uplifted mountain type, on the island. The sedimentary basin-type hot dry rocks are mainly found in the north of the island and have an area of 2657 km2, an average depth of 2480 m, and an average heat reservoir temperature of 230 °C at 6000 m depth. Uplifted mountain-type hot dry rocks with a total area of 13,000 km2 mainly occur in Danzhou in the north of the island and Baocheng in the south. The heat reservoirs of these rocks are Yanshanian intrusive plutons and the average temperature is 236 °C at 6000 m depth. Nine favorable hot dry rock targets are identified, of which five are sedimentary basin types and four are uplifted mountain types. The Fushan and Eman depressions in north Hainan Island and the Baocheng Rock Mass in the south of the island are the preferred exploration targets.

As an important component of the exploration and evaluation of geothermal resources, the formation model has unique formation and distribution rule in different regions. Reliable geological models need to be established to help in temperature prediction, favorable area selection, and drilling design studies prior to the development of geothermal resources. This paper provides an integrated approach for analyzing the formation models of geothermal resources by combining geological studies and the wide-field electromagnetic method. The resistivity profile is converted into a geologic profile by analyzing the fault distribution, stratigraphic lithology, magmatic rock development, and signal changes of the profile. Comprehensively analyzing the geological elements including the heat sources, water sources, thermal reservoirs, transport conditions, cap rock, and preservation conditions, we investigate the matching relationship of the geological elements on the geologic profile and establish a formation model of the geothermal resources. This approach avoids the respective limitations of geological and geophysical methods, and the formation model established by this approach is comprehensive, intuitive, and accurate and can provide support for the development of geothermal resources.

Among the various technologies for hydrogen production, the renewable energy driven water electrolysis has emerged as a favorable method. In this respect, the present research proposes and analyses a novel and efficient medium-temperature driven geothermal system for green hydrogen production. An alkaline electrolyzer is deployed for hydrogen production which is powered by a double flash steam geothermal power cycle. To boost the power generation (and hence the hydrogen production amount) the double flash cycle is equipped with a self-superheating process, which superheats the saturated vapor at turbine inlet without using another external heat source. Thermodynamic evaluations, based on exergy concept, along with economic analysis are carried out to assess the hydrogen production amount, plant exergy efficiency and total cost rate, and the unit hydrogen price. In order to represent a comprehensive investigation of the plant performance, parametric analyses along with single- and multi-criteria optimizations were conducted. The results revealed that, for 1 kg / s of geothermal brine, the capacity of hydrogen production of the proposed plant is ∼ 1.5 − 3 kg / h under various operating conditions. It is found that, under multi-objective optimum operating conditions, the plant yields 12.63% exergy efficiency and its total cost rate is calculated to be 10.42 $/h. However, if the plant is to be optimized for maximum exergy efficiency, the value of 14.25 % is achievable which will result in increment of total cost rate to 11.97 $/h. [ABSTRACT FROM AUTHOR]

The permeability of reservoirs is a key factor affecting the exploitation and utilization of geothermal resources. This test used a core flow meter and other advanced experimental devices to investigate the evolution of the permeability characteristics of loose sandstone samples (with a diameter of 25 mm and a length of 50 mm) in the Zijiao Town area under various temperatures, confining pressures, injection rates, and cyclic loading and unloading conditions. The results show that (1) as the temperature increases, the overall trend of rock permeability decreases, which is mainly related to the thermal expansion of rock particles. In addition, the higher the temperature, the greater the gravel outflow. (2) The critical pressure for pore closure in the unconsolidated sandstone in the region is approximately 15 MPa. (3) The permeability change of loose sandstone under low injection rate conditions is relatively small and can be neglected. However, there is reason to believe that under high-flow injection conditions, the permeability of this type of rock mass will undergo significant changes. (4) Under the condition of loading and unloading, the permeability ratio curve of the unloading stage at three temperatures is almost a straight line. The higher the temperature, the smaller the slope, and the permeability at 20 °C with the highest recovery degree is only about 50% of the initial one. [ABSTRACT FROM AUTHOR]

Accurately determining the favorable areas of geothermal resources and selecting the target positions of exploration wells are extremely important for exploration and efficient development. This study used the Pearson correlation coefficient and Gini gain to analyze five influencing factors related to the presence of economically viable geothermal potential. The evaluation model of the favorable areas was constructed by using different Machine Learning (ML) methods: Bayesian classifier (Bayes), Support Vector Machine, Bootstrap Aggregating (Bagging), BP neural network, Decision Tree and Logistic Regression classification. The quality of each model was verified by statistical evaluation indicators: Accuracy (ACC), F1 score (F1) and Receiver Operating Characteristic curve (ROC curve). The methodology was applied to the case study of Xinjiang Uygur Autonomous Region, China. Due to the results obtained, all ML models showed strong prediction and classification performance on the target area selection of geothermal exploration, as evidenced by each model’s metrics: the ACC was above 80%, the F1 was above 0.8, and the Area Under the ROC Curve (AUC) was greater than 0.85. The metrics obtained by the Bagging method were the highest. Finally, the results of the six ML models were combined to classify the study area’s geothermal potential, which was consistent with the available information. This study provides a specific basis and technical support for applying the method in further surveys and campaigns. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainability of geothermal energy is related with the type of geothermal resources (natural springs, well), usage situations (thermal, residential-greenhouse heating, energy, etc.), amount of use (optimal flow, appropriate pressure-temperature changes), conservation of resources, and is mostly achieved by reinjection of the geothermal fluid returning from usage. It is important to take measures to prevent adverse changes in temperature and pressure conditions in the reservoir to properly remove the fluid returning from use in geothermal areas from the environment and recharge the reservoir. Reinjection should be carried out under appropriate conditions for the protection of resources. In the operation of geothermal resources, reinjection/discharge conditions and obligations are also specified in the provisions of the Law No. 5686 and the implementing regulation. Various studies within the scope of exploration activities in geothermal fields, determining the production-reinjection areas and determination the location of the reinjection wells in conditions that will not adversely affect the production

With the rapid economic development in North China, the demand for geothermal energy is increasing. It is urgent to find favorable deep geothermal resource targets in North China. Although geothermal resources in the North China Plain are widely distributed, in order to develop deep geothermal resources in North China safely, stably and efficiently, it is essential to carry out the target selection and evaluation of geothermal resource zoning. This article takes the typical geothermal fields in the central Hebei region as the research object, and through the comprehensive collation of regional geothermal geological data, constructs an optimization evaluation indicator system for geothermal resource target areas from three aspects: resource conditions, mining potential, and heating demand. On this basis, it establishes a linear relationship between the attribute values and scores of each indicator, and uses the analytic hierarchy process to assign weights to each indicator and calculate the comprehensive weight. Then, the comprehensive evaluation value is obtained by weighted calculation of the scores and comprehensive weights of each block in the grid segmentation of the evaluation area. Finally, through the spatial analysis function of GIS, the comprehensive evaluation values of all blocks in the evaluation area were analyzed using kriging difference analysis, and a comprehensive evaluation map, the geothermal resource prospective target area map, was finally obtained. Using quantitative zoning evaluation methods, the target areas for exploration and development of deep geothermal resources in central Hebei Province have been delineated within a large region. The evaluation results indicate that the Cambrian-Ordovician reservoir target area is relatively large, and there are many favorable target areas with good reservoir conditions in the Middle-Upper Proterozoic. The excellent prospective target area of the Mesoproterozoic geothermal reservoir accounts for 56%, mainly located in the Xingji uplift and Gaoyang low uplift. Xiong’an New Area, Cangzhou, and the eastern part of Hengshui are excellent prospective target areas for the evaluation of the Mesoproterozoic geothermal reservoir in a single area. This evaluation method can provide a reference for the optimization of resource exploration and development target areas in key regions.

The lithospheric thermal structure has a profound indicative significance for the potential evaluation and exploration of geothermal resources. The Linyi geothermal field, located in the southern section of the Yishu fault in Shandong Province, boasts abundant geothermal resources. However, its origin is still unclear. This study analyzed the characteristics of terrestrial heat flow using the temperature logging of geothermal wells and measurements of thermal conductivity and heat production. Combined with the geophysical information of the Xiangshui (Jiangsu Province)-Mandula (Nei Mongol) geoscience transect and the lithology revealed by the geothermal wells, this study built a conceptual model of the lithospheric thermal structure using the one-dimensional steady-state heat conduction equation. Based on this model, the heat flow is 64.9 mW/m2, indicating a high geothermal setting in the study area. Furthermore, the ratio of crustal to mantle heat flow is < 1 (0.67), implying that surface heat flow originates predominantly from the mantle. The Yishu fault probably acts as a pathway for heat transfer from the mantle. The temperature of the Moho boundary in the study area was estimated to be 614.8 °C. The Curie depth was calculated to be 29.5 km (585 °C), which is consistent with the depth estimated using the aeromagnetic data. In sum, the Linyi geothermal field has a high geothermal setting, which contributes to the formation of geothermal resources. [ABSTRACT FROM AUTHOR]

The Maichen Sag in the south-central part of the Beibuwan Basin is abundant in geothermal resources that have not been widely exploited and utilized due to inadequate research on it. This study evaluated the geothermal resources in the Maichen Sag based on the regional geological setting and geothermal conditions. Grid units for assessment and a geological model for areas with geothermal resources were established using spatial analysis techniques. The spatial distribution models of the physical and thermophysical properties of the geothermal reservoirs were also built using the Kriging interpolation method. Based on the terrestrial heat flow distribution in the target areas, the spatial distribution of the geo-temperature field through the inversion under the constraints of the temperature data from boreholes were predicted. Factors such as deep geo-temperature, thermophysical properties of rocks, and terrestrial heat flow values, were integrated into this quantitative evaluation of geothermal resources through the geological modeling-based volume method and the geothermal reservoir engineering-based numerical simulation method. The results show that the Maichen Sag has favorable heat source conditions with intersected, deep-rooted faults and widely developed Upper Paleozoic fissured granite geothermal reservoirs. The northern outer slope zone at a burial depth of 3-5 km on the tectonic plane of the basement in the sag is suggested to be a potential target area, where, as calculated using the volume method, is likely to be the home to the total geothermal resources of 80.4x109GJ (i.e., 2.75x109tonnes of coal equivalent (tce)) in the bedrock geothermal reservoirs at a burial depth of 3-6 km. The geotemperature of 172-201°C at a formation depth of 5 km in the sag also indicates that the deep geothermal resources are of high value for exploitation. [ABSTRACT FROM AUTHOR]

The Ganzi geothermal field is located in the Songpan-Ganzi orogenic belt in Sichuan Province. Many hot springs are exposed along the Yalahe valley in Ganzi geothermal field, which is a favorable area for hightemperature geothermal resource exploration. However, the geological model of heat exchange, the regional structure controlling hydrothermal convection and the development model of geothermal reservoirs are still unclear. Therefore, further studies are necessary to meet the geothermal exploration requirements in the middle and deep strata of this geothermal field. In this study, a geological model of the geothermal system of Ganzi geothermal field is proposed. We are convinced that there exists a hydrothermal convection system in the Ganzi geothermal field, the heat transfer of which is accomplished through deep-rooted major faults. Therefore, the identification of deep-rooted major faults and the description of geothermal reservoirs are the research objects of the integrated geophysical methods. The main factors controlling the geothermal reservoirs in the deep-rooted Xianshuihe major fault and Yalahe fault zones are analyzed by using gravity, aeromagnetic, and electromagnetic methods and techniques. The analysis results of regional gravity and aeromagnetic anomalies show that the Xianshuihe major fault has produced obvious gravity and aeromagnetic anomalies on the surface, and thus the position and strike of this fault can be accurately predicted by inversion of the aeromagnetic anomalies. Geothermal reservoirs show low-resistivity anomalies in the electromagnetic profile. The inversion results of the controlled source audio-frequency magnetotelluric (CSAMT) data show that geothermal reservoirs are mainly developed along the Yalahe valley, and the west side of the valley is more favorable for geothermal exploration. This study is of guiding significance to the efficient exploitation and utilization of the Ganzi geothermal field. [ABSTRACT FROM AUTHOR]

Geothermal energy is an eco-friendly, renewable source of underground thermal energy that exists in the interior of the earth. By tapping into these formations, fluids can be channeled to heat the rock formations above, resulting in a significantly higher land surface temperature (LST). However, LST readings are influenced by various factors such as sun radiation, cyclical variations, and precipitation, which can mask the temperature anomalies caused by geothermal heat. To address these issues and highlight the LST anomalies caused by geothermal heat, this paper proposes a methodology to efficiently and quickly calculate the multi-temporal LST leveraging of the Google Earth Engine (GEE) in the Damxung–Yangbajain basin, Qinghai–Tibet Plateau. This method incorporates terrain correction, altitude correction, and multi-temporal series comparison to extract thermal anomaly signals. The existing geothermal manifestations are used as a benchmark to further refine the methodology. The results indicate that the annual mean winter LST is a sensitive indicator of geothermal anomaly signals. The annual mean winter LST between 2015 and 2020 varied from −14.7 °C to 26.7 °C, with an average of 8.6 °C in the study area. After altitude correction and water body removal, the annual mean winter LST varied from −22.1 °C to 23.3 °C, with an average of 6.2 °C. When combining the distribution of faults with the results of the annual mean winter LST, this study delineated the geothermal potential areas that are located predominantly around the fault zone at the southern foot of the Nyainqentanglha Mountains. Geothermal potential areas exhibited a higher LST, ranging from 12.6 °C to 23.3 °C. These potential areas extend to the northeast, and the thermal anomaly range reaches as high as 19.6%. The geothermal potential area makes up 8.2% of the entire study area. The results demonstrate that the approach successfully identified parts of known geothermal fields and indicates sweet spots for future research. This study highlights that utilizing the multi-temporal winter LST is an efficient and cost-effective method for prospecting geothermal resources in plateau environments. [ABSTRACT FROM AUTHOR]

The Sichuan Basin located in the intersection of the Tethys−Himalaya and Pacific domains is a multicycle sedimentary basin surrounded by orogenic belts. The geothermal resources are good, but with complex geological structures. Geothermal conditions and heat generation models are different in different tectonic zones in the basin, which seriously restrict the geothermal exploration, development and utilization of geothermal resources. In this paper, the distribution of geothermal resources, characteristics of geothermal fluids, heat flow and geothermal gradients in the Sichuan Basin are comprehensively analyzed by collecting the existing geothermal and petroleum exploration and development data. The geothermal reservoirs and caprocks, the burial depth and the resource conditions of different types of the basin-mountain structure areas in the Sichuan Basin are analyzed. The suggested exploration target for exploration and development are proposed in different tectonic units of the Sichuan Basin. The results show (1) the terrestrial heat flow values in the Sichuan Basin and its surrounding areas are from medium to low, and the geothermal gradient varies between 16 °C/km and 30 °C/km. The terrestrial heat source is obviously controlled by active faults and basement structure, and the hydrothermal systems are conductive and belong to the low-moderate temperature geothermal resources in the Sichuan Basin. (2) The distribution of geothermal resources in the Sichuan Basin is mainly controlled by basin structure, stratigraphic distribution and hydrologic conditions. (4) There are at least 4 karst-type geothermal reservoirs in the marine strata, and 1 − 2 glutenite-type geothermal reservoirs in clastic strata. Geothermal water is of SO4—Ca type and is brackish. The Middle-Lower Triassic and Middle Permian carbonate rocks are considered as the best marine reservoirs, especially in the eastern and western basin. Secondly, other marine karst-type geothermal reservoirs are selected for exploration. The continental clastic rocks should be cautious because their caprocks, groundwater recharge and heat source are worse than the geothermal conditions of the marine carbonate rocks. This study may provide important guidance for further promoting geothermal exploration, exploitation and utilization in the Sichuan Basin.

The Gonghe Basin, situated on the northeastern margin of the Qinghai–Tibet Plateau, is a strike-slip pull-apart basin that has garnered considerable attention for its abundant high-temperature geothermal resources. However, as it is located far from the Himalayan geothermal belt, research on the geothermal resources in the Gonghe Basin has mainly focused on the heat source mechanism, with less attention given to the distribution and resource potential of hot dry rock. In this project, a comprehensive approach combining geological surveys, geophysical exploration, geochemical investigations, and deep drilling was employed to analyze the stratigraphic structure and lithological composition of the Gonghe Basin, establish a basin-scale three-dimensional geological model, and identify the lithological composition and geological structures within the basin. The model revealed that the target reservoirs of hot dry rock in the Gonghe Basin exhibit a half-graben undulation pattern, with burial depths decreasing from west to east and reaching a maximum depth of around 7000 m. Furthermore, the distribution of the temperature field in the area was determined, and the influence of temperature on rock density and specific heat was investigated to infer the thermal properties of the deep reservoirs. The Qiabuqia region, situated in the central-eastern part of the basin, was identified as a highly favorable target area for hot dry rock exploration and development. The volume method was used to evaluate the potential of hot dry rock resources in the Gonghe Basin, which was estimated to be approximately 4.90 × 1022 J, equivalent to 1.67 × 1012 t of standard coal, at depths of up to 10 km. [ABSTRACT FROM AUTHOR]

The Xiongxian geothermal field is among the areas with most favorable geological settings for medium-temperature geothermal resources in north China, and has a long exploitation history. As heat-mining intensity increases, the research on the genetic mechanism of the geothermal field has become crucial for evaluating its remaining resource reserve and designing future exploitation schemes. On the basis of previous research results, the source and reservoir residence time of the geothermal fluids of the Xiongxian geothermal field were studied by applying environmental isotopes. The connectivity and runoff relationships among the thermal reservoirs were preliminarily analyzed in terms of the hydrochemical characteristics of geothermal fluids. The results indicate that the geothermal fluids in Xiongxian are primarily of paleo-precipitation origins, with an age of 31~36 ka, and the groundwater is heated up by the geothermal warming during the long-term runoff process. Under natural conditions, the hydraulic connection between the Neoproterozoic geothermal fluids and the upper aquifer, as well as geothermal fluids from other aquifers are weak. By analyzing the tectonic background, thermal reservoir characteristics and geothermal formation mechanism in the Xiongxian geothermal exploitation area, a three-dimensional geological model and a mathematical numerical model of the thermal reservoir were established. A hydrothermal coupling simulation of the hydrothermal production-reinjection scheme in the region was carried out. The calculation results fit well with the thermal reservoir temperature measurement data and pumping test data. Based on the validated model, the geothermal resource reserves in the study area were evaluated, and the design of well-spacing and flow rate were optimized for the study area. When the extraction flow rate is 120 m³ / h and the well spacing is 450 m, the annual extractable heat is 12. 9 × 10 15 J/ a and the extractable water is 56. 6 × 106 m³ / a, which is equivalent to 442 000 t of standard coal. Scenario simulation shows that the water temperature of the extraction well would decrease less than 2 ℃ within 100 years. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainability of geothermal energy is related with the type of geothermal resources (natural springs, well), usage situations (thermal, residential-greenhouse heating, energy, etc.), amount of use (optimal flow, appropriate pressure-temperature changes), conservation of resources, and is mostly achieved by reinjection of the geothermal fluid returning from usage. It is important to take measures to prevent adverse changes in temperature and pressure conditions in the reservoir to properly remove the fluid returning from use in geothermal areas from the environment and recharge the reservoir. Reinjection should be carried out under appropriate conditions for the protection of resources. In the operation of geothermal resources, reinjection/discharge conditions and obligations are also specified in the provisions of the Law No. 5686 and the implementing regulation. Various studies within the scope of exploration activities in geothermal fields, determining the productionreinjection areas and determination the location of the reinjection wells in conditions that will not adversely affect the production pressure-temperature conditions are of great importance for the sustainability of the geothermal reservoir. [ABSTRACT FROM AUTHOR]

The geothermal resource is a kind of clean, low-carbon and recyclable renewable energy. Under the background of “dual carbon” target policy, developing geothermal energy has realistic and strategic significance in adjusting energy structure and upgrading and ecological civilization construction. The exploration of geothermal resource is the premise and basis of geothermal energy development and utilization's depth and breadth. On the basis of elaborating the geothermal resource distribution situation China's shallow layer type, hydrothermal type and dry hot rock type, the mechanism, research progress, advantages and disadvantages of remote sensing, geophysics and geochemistry technologies commonly used in geothermal resource exploration were described. All single exploration technologies have certain limitation and applicability. In the future, key research should be carried out in integrated application of geothermal exploration technology, new exploration technology development and high precision device development, sequentially promote the extent and precision of geothermal resource exploration and evaluation, provide technical reference for China's future geothermal resource exploration, development and utilization. [ABSTRACT FROM AUTHOR]

The Songliao Basin is a key geothermal resource area for medium and low temperature geothermal energy in China. Using the latest seismic imaging data, combined with the gravity, geomagnetism and geothermal observation data and the relationship between basin tectonic evolution and mantle heat flow, the heat distribution ratio of deep and shallow strata, the depth of Moho surface and Curie surface, and the heat generation rate structure in Songliao Basin were calculated. The results show that ① the geothermal field of the shallow crust in Songliao Basin is dominated by conductive heat transfer; ② although the Moho surface in the center of the basin is uplifted, the heat flow of the upper mantle is in a state of decay and decline, and the heating of the upper mantle is insufficient, resulting in a relatively low temperature of the Moho surface; ③ the Curie surface in the center of the basin is deeper, which is related to the thermal relaxation of the upper mantle; above the Curie surface, the geothermal gradient is high due to the higher radioactive heat generation rate of granite; under the Curie surface, the geothermal gradient decreases due to the attenuation and fall of the mantle heat flow. It is considered that the upper mantle in the central depression is in the thermal relaxation stage of heat flow attenuation, and its contribution to the surface heat flow is less than that of the radioactive heat generation in the upper crust. The origin of surface thermal anomaly in the central Songliao Basin is mainly the radioactive heat generation of granite in the upper crust. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Asociación Geológica Argentina is the property of Asociacion Geologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The permeability of reservoirs is a key factor affecting the exploitation and utilization of geothermal resources. This test used a core flow meter and other advanced experimental devices to investigate the evolution of the permeability characteristics of loose sandstone samples (with a diameter of 25 mm and a length of 50 mm) in the Zijiao Town area under various temperatures, confining pressures, injection rates, and cyclic loading and unloading conditions. The results show that (1) as the temperature increases, the overall trend of rock permeability decreases, which is mainly related to the thermal expansion of rock particles. In addition, the higher the temperature, the greater the gravel outflow. (2) The critical pressure for pore closure in the unconsolidated sandstone in the region is approximately 15 MPa. (3) The permeability change of loose sandstone under low injection rate conditions is relatively small and can be neglected. However, there is reason to believe that under high-flow injection conditions, the permeability of this type of rock mass will undergo significant changes. (4) Under the condition of loading and unloading, the permeability ratio curve of the unloading stage at three temperatures is almost a straight line. The higher the temperature, the smaller the slope, and the permeability at 20 °C with the highest recovery degree is only about 50% of the initial one.

Among so many fault basins around Ordos presenting good geothermal background, Yinchuan Plain is the key development and protection area of the Ecological and Economic Belt along the Yellow River in Ningxia and Yinchuan Metropolitan Area. The study of geothermal resources in this region is of great significance to the sustainable economic development of Yinchuan Plain. Most scholars suggested that Yinchuan Plain geothermal resources are low-to-medium temperature geothermal resources and have high value in terms of development and utilization due to their large reserves, good water quality conditions, and wide distribution. However, there is much controversy over the geothermal mechanism of this region. As an effective means to study geothermal mechanism, geophysical methods can be used to study regional basement uplift and structural distribution characteristics. Based on the discussion of regional geothermal geology background, this paper studies the distribution rules of Moho and Curie depths in the region by applying different geophysical data. The results show that the western margin of Yinchuan Plain is obviously uplifted. As inferred from the epicentral distribution of Yinchuan Plain section, there is a significant difference of the seismic bottom interface on the east and west sides of the Yellow River fault in Yinchuan Plain. The three-dimensional gravity inversion confirms basement uplift in this region. By referring to results obtained by the inversion of gravity and magnetic data and deep seismic exploration, the paper presents a comprehensive analysis of the regional geothermal geology conditions and proposes a geothermal conceptual model of Yinchuan Plain. The heat source comes from the earth heat flow and migrates to the thermal reservoir through the fault or fissure convection. The deep-large active faults provide a channel for deep heat flow to the shallow part, and the thermal fluid accumulates in the uplift area to form the high geothermal anomaly area. There should be two large-scale geological activities in the geotropics around Ordos. One is the basement uplift of the basins around Ordos platform, which provide the heat source. The other is the uplift of Ordos, which places the surrounding basin in an extensional environment and provides a channel for the heat source upwelling. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Mangkang geothermal field, distributed in the Mediterranean–Himalayas geothermal belt, hosts abundant hot springs whose geneses remain unclear. To determine the hydrochemical characteristics, reservoir temperature, circulation and recharge depths, and water–rock interactions of the geothermal water in the geothermal field, this study analyzed hydrochemical compositions and isotopes (2H, 3H, and 18O), conducted a PHREEQC simulation, and established a conceptual model to illustrate the genesis of geothermal resources in the Mangkang field. Based on the study of hot springs in Meipu, Qvzika, and Zulongpu villages and Rumei town, the following results are reported: The orifice temperatures of these hot springs vary between 18 °C and 67.5 °C. The hydrochemical composition analysis results indicate that the geothermal water in the hot springs is of hydrochemical type HCO3-Ca·Mg. Moreover, the geothermal water has high HBO2 and Na+ concentrations, suggesting protracted water runoff and strong water–rock interactions during its evolution. According to the mineral–water solubility equilibrium and silica geothermometers, it is estimated that the reservoir temperature of the Zulongpu hot spring is 47 °C and other hot springs have much higher reservoir temperatures of 116–130 °C. As indicated by geothermal gradients, annual temperatures, and reservoir temperatures, the geothermal water in Meipu and Qvzika villages has the greatest circulation depth, up to 3600–4300 m, followed by that in Rumei town (3700–4000 m) and Zulongpu village (~1500 m). The 2H-18O isotopic analysis of the geothermal surface water revealed that the geothermal water originates from meteoric water. The recharge elevation was inferred to be ~4700–4900 m. Moreover, the low 3H values (<1 Tu) suggest that the geothermal water is older than 40 years. The PHREEQC inverse simulation results indicated that the variation in the hydrochemical composition of the geothermal water results from the precipitation of chalcedony and dolomite, the absorption of NaX, and the loss of CaX2 during migration and storage. [ABSTRACT FROM AUTHOR]

Geothermal energy is an eco-friendly, renewable source of underground thermal energy that exists in the interior of the earth. By tapping into these formations, fluids can be channeled to heat the rock formations above, resulting in a significantly higher land surface temperature (LST). However, LST readings are influenced by various factors such as sun radiation, cyclical variations, and precipitation, which can mask the temperature anomalies caused by geothermal heat. To address these issues and highlight the LST anomalies caused by geothermal heat, this paper proposes a methodology to efficiently and quickly calculate the multi-temporal LST leveraging of the Google Earth Engine (GEE) in the Damxung–Yangbajain basin, Qinghai–Tibet Plateau. This method incorporates terrain correction, altitude correction, and multi-temporal series comparison to extract thermal anomaly signals. The existing geothermal manifestations are used as a benchmark to further refine the methodology. The results indicate that the annual mean winter LST is a sensitive indicator of geothermal anomaly signals. The annual mean winter LST between 2015 and 2020 varied from −14.7 °C to 26.7 °C, with an average of 8.6 °C in the study area. After altitude correction and water body removal, the annual mean winter LST varied from −22.1 °C to 23.3 °C, with an average of 6.2 °C. When combining the distribution of faults with the results of the annual mean winter LST, this study delineated the geothermal potential areas that are located predominantly around the fault zone at the southern foot of the Nyainqentanglha Mountains. Geothermal potential areas exhibited a higher LST, ranging from 12.6 °C to 23.3 °C. These potential areas extend to the northeast, and the thermal anomaly range reaches as high as 19.6%. The geothermal potential area makes up 8.2% of the entire study area. The results demonstrate that the approach successfully identified parts of known geothermal fields and indicates sweet spots for future research. This study highlights that utilizing the multi-temporal winter LST is an efficient and cost-effective method for prospecting geothermal resources in plateau environments.

Geothermal resources are one of the most valuable renewable energy sources because of their stability, reliability, cleanliness, safety and abundant reserves. Efficient and economical remote sensing and GIS (Geographic Information System) technology has high practical value in geothermal resources exploration. However, different study areas have different geothermal formation mechanisms. In the process of establishing the model, which factors are used for modeling and how to quantify the factors reasonably are still problems to be analyzed and studied. Taking Hangjiahu Plain of Zhejiang Province as an example, based on geothermal exploration and remote sensing interpretation data, the correlation between the existing geothermal hot spots and geothermal related factors was evaluated in this paper, such as lithology, fault zone distance, surface water system and its distance, seismic point distance, magmatic rock and volcanic rock distance, surface water, farmland, woodland temperature and so on. The relationship between geothermal potential and distribution characteristics of surface thermal environment, fault activity, surface water system and other factors was explored. AHP (Analytic Hierarchy Process) and BP (Back Propagation) neural network were used for establishing geothermal potential target evaluation models. The potential geothermal areas of Hangjiahu Plain were divided into five grades using geothermal exploration model, and most geothermal drilling sites were distributed in extremely high potential areas and high potential areas. The results show that it is feasible to analyze geothermal potential targets using remote sensing interpretation data and geographic information system analysis databased on analytic hierarchy process analytic hierarchy process and back propagation neural network, and the distribution characteristics of surface thermal environment, fault activity, surface water system and other related factors are also related to geothermal distribution. The prediction results of the model coincide with the existing geothermal drilling sites, which provides a new idea for geothermal exploration.

İzmir is a city that has rich thermal resources and thus has potential in terms of thermal tourism activities. To continue the sustainability of these resources, it is important to use them effectively in the service production and consumption process, to reduce and recycle the wastes In this context, this study aims to raise awareness about the recycling of the wastes produced in the service production process, especially geothermal resources in thermal accommodation enterprises, within the framework of the circular economy and to conduct a case analysis on the applications in the relevant field. By adopting the qualitative research design, face-to-face interviews were conducted with the managers of a thermal accommodation business operating in İzmir. The data obtained were analyzed with the Maxqda 2020 Pro program and interpreted with descriptive analysis. The most important finding in the research is that the enterprise dumps the wastewater from geothermal sources into the sea for various reasons and does not use the re-injection system. As a result, it is understood that the facility pays attention to sustainability activities even though it cannot fully fulfill the circular economy practices. [ABSTRACT FROM AUTHOR]

Geothermal resources occurring in the Changbaishan volcanic field are directly or indirectly controlled by volcanic activity and exhibit a close correlation with deep-seated faults. Energy and thermal transfer are generally controlled by groundwater circulation and hot gas emission. This article considers the detectability of hot water and gas by geophysical methods. The controlled source acoustic magnetotelluric (CSAMT) and radon (222Rn) gas methods give straightforward information on electrical resistivity and natural radon emissions, respectively, to assess the geothermal condition. The CSAMT method detected five-banded low-apparent resistivity bodies (decreasing from 3,000 to 300 Ωm), indicating that there exists a high degree of water-bearing capacities in the subsurface. The radon (222Rn) gas concentrations were monitored in two rapid growth zones: one zone showing values ranging from 3,000 to 23,000 Bq/m3, and the other with values from 4,000 to 24,000 Bq/m3. These changes demonstrate that the heat energies available in these areas were very high and that there is potential for geothermal resources in those zones. Combining with previously published data from geothermometry and geothermal drilling, we argue that there is great potential in Erdaobaihe for geothermal exploitation and that the geothermal resource type should be classified into uplift mountain geothermal system no magma type.

The Gonghe Basin, situated on the northeastern margin of the Qinghai–Tibet Plateau, is a strike-slip pull-apart basin that has garnered considerable attention for its abundant high-temperature geothermal resources. However, as it is located far from the Himalayan geothermal belt, research on the geothermal resources in the Gonghe Basin has mainly focused on the heat source mechanism, with less attention given to the distribution and resource potential of hot dry rock. In this project, a comprehensive approach combining geological surveys, geophysical exploration, geochemical investigations, and deep drilling was employed to analyze the stratigraphic structure and lithological composition of the Gonghe Basin, establish a basin-scale three-dimensional geological model, and identify the lithological composition and geological structures within the basin. The model revealed that the target reservoirs of hot dry rock in the Gonghe Basin exhibit a half-graben undulation pattern, with burial depths decreasing from west to east and reaching a maximum depth of around 7000 m. Furthermore, the distribution of the temperature field in the area was determined, and the influence of temperature on rock density and specific heat was investigated to infer the thermal properties of the deep reservoirs. The Qiabuqia region, situated in the central-eastern part of the basin, was identified as a highly favorable target area for hot dry rock exploration and development. The volume method was used to evaluate the potential of hot dry rock resources in the Gonghe Basin, which was estimated to be approximately 4.90 × 1022 J, equivalent to 1.67 × 1012 t of standard coal, at depths of up to 10 km.

This project updates the geothermal resources beneath our oil and gas fields, as part of the research for the Texas GEO project for the counties of Crockett, Jackson and Webb. Through additional bottom-hole temperatures from oil and gas wells drilled in the late 1990s to 2019, the number of sites increased from 532 to 5,410. The project improved the methodology to calculate formation temperatures from 3.5 km to 10 km, included thermal conductivity values more closely related to the actual county geological formations, and incorporated radiogenic heat production of formations and the related mapped depth to basement. The project results show deep temperatures as hotter than previously calculated, with temperatures of 150 °C possible for Webb County between depths of 2.6 – 5.1 kms, average 3.3 km; Jackson County between depths 3.0 – 5.4 kms, average 3.7 km; and Crockett County between depths of 2.7 – 8.0 kms, average 4.0 km. Based on the 150 °C temperature desired for electrical production, 677 wells or 11.6 % of them have at least this temperature or higher. The oil and gas industry can be a significant resource for unlocking our ability as a nation to extract the geothermal heat resource.

The prediction of the geothermal field is an important prerequisite for the evaluation of geothermal resources. Much attention has been paid to the research on coupled temperature field of percolation-heat transfer in deep fractured rock mass. The Zhuolu Basin is a graben-type faulted basin of the Cenozoic era. There are many hot springs on the surface and rich geothermal resources. In this paper, a three-dimensional non-parallel multi-fractured geological model of the Zhuolu Basin for large scale was established based on the actual geological survey results and the geological structure section interpreted by 3 geophysical survey lines. Parameters have been assigned or adjusted, a mathematical model of permeate-heat transfer in multi-fractured rock mass considering groundwater flow was obtained. After the model was verified, the internal temperature field of the basin was calculated and indicated. The geothermal anomaly area is concentrated in the center of the Jixian group (around 70℃) and the north- eastern part of the Changcheng group (90~98℃), the internal temperature field of basin have been analyzed at different hydraulic reaolients. The study results provide a certain basis for the exploration, evaluation, development and utilization of geothermal resources in Zhuolu Basin or similar areas.

The Southern Methodist University Geothermal Laboratory updated their quantification of the geothermal resources within and beneath the Texas oil and gas fields in Crockett, Jackson, and Webb counties as part of the research for the University of Texas Geothermal Entrepreneurship Organization research project DE-EE0008791. Through additional well sites drilled since 2000, the number of bottom-hole temperatures increased from 532 to 5,410. The research improved the methodology to calculate formation temperatures from 3.5 to 10 kilometers (11,480 to 32,800 feet) by using thermal conductivity values more closely related to the county geological formations, incorporating radiogenic heat production of geological formations, and updating the depth to the basement rocks. The results show deep temperatures as hotter than previously calculated, with temperatures of 150 °C (300 °F) possible for Webb, Jackson, and Crockett Counties on average at depths of 3.3, 3.7, and 4.0 kilometers (10,800, 12,100, and 13,100 feet), respectively. A target temperature of 150 °C is considered the minimum for efficient power generation, although cooler temperatures can be useful in other low-temperature applications. Therefore, geothermal resources are a new way to diversify the local electric grid with a baseload renewable energy option. It has the potential of making a significant energy contribution in the future. [ABSTRACT FROM AUTHOR]

The Roosevelt Hot Springs Known Geothermal Resource Area (KGRA) is a Basin and Range‐type geothermal resource, which is located in southwestern Utah. The integrated multicomponent geothermometry (IMG) approach is used to estimate the reservoir temperature at the Roosevelt Hot Springs KGRA. Geothermometric modeling results indicate the deep reservoir temperature is approximately 284.6°C. A conceptual model of the Roosevelt Hot Spring KGRA is provided through integrating the various pieces of exploration information, including the geological data, geothermometric results, temperature well log and field evidence. A two‐dimensional cross‐sectional model was thus built to quantitatively investigate the coupled thermal‐hydraulic processes in the Roosevelt geothermal field. By matching the preproduction temperature log data of deep wells, parameters controlling flow and heat transport are identified. The method and model presented here may be useful for other geothermal fields with similar conditions. [ABSTRACT FROM AUTHOR]

Geothermal energy plays an important role in urban construction of the Xiong'an New Area. Geothermal reservoir fracture distribution of the Mesoproterozoic Jixianian Wumishan Formation (Fm.) carbonate reservoir in the Rongcheng geothermal field are evaluated based on FMI log from Wells D19 and D21. The results show carbonate reservoir fracture density of Well D19 is 15.2/100 m, greater than that of Well D21 with a value of 9.2/100 m. Reservoir porosity and permeability of Well D19 are better than that of Well D21, and the water saturation is bimodally distributed. The movable fluid volume ratio (BVM) of Well D19 is 2% to 8% with some zones exceeding 20%, while the value of Well D21 is less than 4%. Therefore, reservoir fractures in Well D19 are more conducive to fluid flow. Reservoir fractures have a similar occurrence to normal faults, indicating that the tensile stress field controlled the formation of such fractures. Developed reservoir fractures provide a good channel for groundwater convection. The circulation of regional groundwater and the heat exchange between water and rock and the multiple heat accumulation patterns form a stable and high potential heat reservoir in the Rongcheng geothermal field. [ABSTRACT FROM AUTHOR]

Assessment of available geothermal resources in the deep oil field is important to the synergy exploitation of oil and geothermal resources. A revised volumetric approach is proposed in this work for evaluating deep geothermal potential in an active oil field by integrating a 3D geological model into a hydrothermal (HT)-coupled numerical model. Based on the analysis of the geological data and geothermal conditions, a 3D geological model is established with respect to the study area, which is discretized into grids or elements represented in the geological model. An HT-coupled numerical model was applied based on the static geological model to approximate the natural-state model of the geothermal reservoir, where the thermal distribution information can be extracted. Then the geothermal resource in each small grid element is calculated using a volumetric method, and the overall geothermal resource of the reservoirs can be obtained by making an integration over each element of the geological model. A further parametric study is carried out to investigate the influence of oil and gas saturations on the overall heat resources. The 3D geological model can provide detailed information on the reservoir volume, while the HT natural-state numerical model addressed the temperature distribution in the reservoir by taking into account complex geological structures and contrast heterogeneity. Therefore, integrating the 3D geological modeling and HT numerical model into the geothermal resource assessment improved its accuracy and helped to identify the distribution map of the available geothermal resources, which indicate optimal locations for further development and utilization of the geothermal resources. The Caofeidian new town Jidong oil field serves as an example to depict the calculation workflow. The simulation results demonstrate in the Caofeidian new town geothermal reservoir that the total amount of geothermal resources, using the proposed calculation method, is found to be 1.23e+18 J, and the total geothermal fluid volume is 8.97e+8 m3. Moreover, this approach clearly identifies the regions with the highest potential for geothermal resources. We believe this approach provides an alternative method for geothermal potential assessment in oil fields, which can be also applied globally.

Among so many fault basins around Ordos presenting good geothermal background, Yinchuan Plain is the key development and protection area of the Ecological and Economic Belt along the Yellow River in Ningxia and Yinchuan Metropolitan Area. The study of geothermal resources in this region is of great significance to the sustainable economic development of Yinchuan Plain. Most scholars suggested that Yinchuan Plain geothermal resources are low-to-medium temperature geothermal resources and have high value in terms of development and utilization due to their large reserves, good water quality conditions, and wide distribution. However, there is much controversy over the geothermal mechanism of this region. As an effective means to study geothermal mechanism, geophysical methods can be used to study regional basement uplift and structural distribution characteristics. Based on the discussion of regional geothermal geology background, this paper studies the distribution rules of Moho and Curie depths in the region by applying different geophysical data. The results show that the western margin of Yinchuan Plain is obviously uplifted. As inferred from the epicentral distribution of Yinchuan Plain section, there is a significant difference of the seismic bottom interface on the east and west sides of the Yellow River fault in Yinchuan Plain. The three-dimensional gravity inversion confirms basement uplift in this region. By referring to results obtained by the inversion of gravity and magnetic data and deep seismic exploration, the paper presents a comprehensive analysis of the regional geothermal geology conditions and proposes a geothermal conceptual model of Yinchuan Plain. The heat source comes from the earth heat flow and migrates to the thermal reservoir through the fault or fissure convection. The deep-large active faults provide a channel for deep heat flow to the shallow part, and the thermal fluid accumulates in the uplift area to form the high geothermal anomaly area. There should be two large-scale geological activities in the geotropics around Ordos. One is the basement uplift of the basins around Ordos platform, which provide the heat source. The other is the uplift of Ordos, which places the surrounding basin in an extensional environment and provides a channel for the heat source upwelling.

The Mangkang geothermal field, distributed in the Mediterranean–Himalayas geothermal belt, hosts abundant hot springs whose geneses remain unclear. To determine the hydrochemical characteristics, reservoir temperature, circulation and recharge depths, and water–rock interactions of the geothermal water in the geothermal field, this study analyzed hydrochemical compositions and isotopes (2H, 3H, and 18O), conducted a PHREEQC simulation, and established a conceptual model to illustrate the genesis of geothermal resources in the Mangkang field. Based on the study of hot springs in Meipu, Qvzika, and Zulongpu villages and Rumei town, the following results are reported: The orifice temperatures of these hot springs vary between 18 °C and 67.5 °C. The hydrochemical composition analysis results indicate that the geothermal water in the hot springs is of hydrochemical type HCO3-Ca·Mg. Moreover, the geothermal water has high HBO2 and Na+ concentrations, suggesting protracted water runoff and strong water–rock interactions during its evolution. According to the mineral–water solubility equilibrium and silica geothermometers, it is estimated that the reservoir temperature of the Zulongpu hot spring is 47 °C and other hot springs have much higher reservoir temperatures of 116–130 °C. As indicated by geothermal gradients, annual temperatures, and reservoir temperatures, the geothermal water in Meipu and Qvzika villages has the greatest circulation depth, up to 3600–4300 m, followed by that in Rumei town (3700–4000 m) and Zulongpu village (~1500 m). The 2H-18O isotopic analysis of the geothermal surface water revealed that the geothermal water originates from meteoric water. The recharge elevation was inferred to be ~4700–4900 m. Moreover, the low 3H values (2 during migration and storage.

The insurance funds belong to efficient measures mitigating risks in geothermal projects, including resource risk. They already exist in some European countries, e.g., France, the Netherlands, Turkey. Recently, the proposals of establishing such funds were elaborated for three countries: Greece, Hungary, and Poland within the framework of the EU-funded project "Developing geothermal and renewable energy projects by mitigating their risks", GEORISK (www.georisk-project.eu). A 10 year operational and financial simulation of the proposed public insurance funds was conducted to prove their sustainability in each of three listed states. It started with the determination of the country-specific premises. The numbers of projects in the next 10 years possible to be covered by funds were assumed by the authors on the bases of realistic estimations. The initial capital, the fixed costs, the costs of the project evaluation, the premium fees paid by the investors, the payment for the unsuccessful projects altogether were taken into account. The first draft simulation was done with the exact Hungarian assumptions and inputs of fixed costs and also with average project data, thus making it appropriate to perform sensitivity analyses on: insurance premiums, success rates and the risk coverages. Then, complete simulations were made for three listed countries. The results of the simulation show that a resource risk insurance fund can be a sustainable and an effective measure to support geothermal energy sector development. During the planning of a new fund, it is important to make use of long experiences both of the former and existing funds. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present research explores the Bañitos-Gollete geothermal field located in the Frontal Andes Cordillera over the Pampean flat-slab. We carried out an audiomagnetotelluric survey in order to define the underground geoelectrical structure and to understand the link between the geothermal fluid path and the main geological structures. 2-D audiomagnetotelluric models suggest that the deep-rooted N-S fault system control the geothermal flow path. We propose a conductive heat-driven system, taking into consideration the geologic setting and the supposed low geothermal gradient of this tectonic environment. The mature Na-Cl waters from Gollete and an estimated reservoir temperature of ~140ºC are consistent with this conceptual model. Further investigations are required to assess the geothermal potential of the study area, and the present work likely represents only the first but necessary step in the exploration process.

Abstract The Liaodong area which lies in the Liaoji Belt of northeastern China is rich in geothermal resources, but locating the resources is challenging. Here non-seismic geophysical data, existing geological data and the physical properties of rocks are examined to locate and characterise potential geothermal resources. High-precision gravity, aeromagnetic and magnetotelluric data are analysed to determine the characteristics of the hidden faults in the region and map the spatial distribution of the subsurface rock mass and its properties. The distribution of hidden faults and the basic characteristics of the rock mass were determined via Euler deconvolution of the gravity and aeromagnetic data. The subsurface extension of concealed faults, the spatial distribution of intrusive rocks, and the specific locations of underground thermal storage structures were determined from magnetotelluric data analysis, thereby enabling geothermal energy targets to be identified. The results highlight four potential sites of geothermal energy development in the study area, which indicate that non-seismic geophysical data can provide reliable clues to the geothermal energy potential in a given region.