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The problem of this research stems from the fact that in Bihor County there are 75 localities that have one or more thermal water wells, of which only 8 locations can provide balneological treatment. The purpose of the research is to evaluate whether the geothermal potential of the region would be sustainable for the development of balneology in other localities as well. In order to meet the above-mentioned requirement, an interdisciplinary methodology was necessary, starting from geophysics and geology, including hydrogeology, chemistry, physics and ending with elements of tourism and balneological potential. The research methods refer to field work, the inventory of all locations that have geothermal resources, the creation of a database, the analysis of the stability and continuity over time of the source of thermalism, the analysis of the stability and time continuity of those physical-chemical properties that are suitable for balneology. In conclusion, out of the 67 locations that still cannot provide balneological treatment, only 20 could fulfil the sustainability criteria and are able to diversify the exploitation of thermal waters. There are 47 other locations that have unexploited boreholes, but despite this, we have come to the conclusion that balneology and tourism based on geothermal waters in Bihor County has a sustainable future in dozens of localities.

The assessment of geothermal potential has gained prominence among scholars, with a focus on establishing a reliable prediction model to reduce development risks. However, little attention has been given to predicting and evaluating the geothermal potential in Dali's Eryuan area. This study introduces a novel hierarchical model integrating remote sensing, a Geographic Information System (GIS), and geophysics for the first-ever effective prediction of geothermal potential in Eryuan. The dataset includes lithology, seismic epicenter data, fault distribution, Bouguer gravity anomalies, SRTM-DEM images, and Landsat 8 remote sensing images. These datasets are converted into evidence maps and normalized to generate distinct evidence factor layers. Using the Analytic Hierarchy Process (AHP), a hierarchical model establishes weights for each evidence factor, resulting in a comprehensive prediction map. The results reveal the overall favorable geothermal potential in Eryuan, except the central area. Key hotspots include the Niujie–Sanying–Gromwell Lake and Liantie–Qiaohou, followed by the Youshou, Dengchuan, and Xixiang towns. Validation against known hot springs confirms the model's accuracy and reliability. [ABSTRACT FROM AUTHOR]

The geothermal field of the platform cover within the Grodno region is considered. The cover rests on a crystalline basement of Precambrian rocks. Temperature distribution maps for depths of 100; 200 and 300 m below ground level were compiled based on thermograms recorded in boreholes and were supplemented by the heat flow map. These reveal geothermal anomalies both of temperature and heat flow density distribution within the region. The temperature in the region monotonously increases with depth, while preserving the general features of the thermal field. The anomalies identified on the 100 m map persist for depths of 200 and 300 m. The main role in the formation of temperature anomalies is played by near-surface factors, such as groundwater circulation, and the influence of paleoclimatic changes on the Earth’s surface in the past. A low heat flow (< 30 mW/m2) in the eastern part of the region gradually increases up to 50 mW/m2 in the vicinity of Grodno. Its areal variation relates to the distribution of granitoid and blastomylonite rocks in the crystalline basement. Increased heat flow is typical of silicic rock massifs with elevated concentrations of long-living radioactive isotopes of uranium, thorium and potassium. Their decay creates an additional radiogenic component of heat flow.

This study intends to determine geothermal anomalies area using remote sensing data in the form of Landsat 8 and ASTER satellite imagery data which have Thermal Infrared Sensor (TIRS). Through pre-processing like georeferencing, radiometric calibration, and atmospheric correction, the Landsat 8 TIRS and ASTER data were wont to invert the land surface temperature of the study area during the daytime and night time using the inversion of planck function and emissivity separation algorithm. Result shows the land surface temperatures during daytime and night time of four natural land cover —water, vegetation, built up area, and bare soil—were classified and analyzed. According to the results, vegetation and bare soil show relatively thermal anomalies during the day and comparatively cold anomalies during the night. Otherwise water shows relatively cold anomalies during the day and relatively thermal anomalies during the night. Meanwhile built up area shows relatively thermal anomalies during the day and cold anomalies during the night. Superimposed and calculating mean of the night and day surface temperature can adequately eliminate the relatively cold/thermal anomalies of land cover caused by solar radiation, thus effectively highlighting geothermal anomalies. Thus, Nine geothermal anomalies areas were successfully extracted.

In this study, we set out to find unusual patterns in specific areas using data from Landsat 8 and ASTER satellites, including Thermal Infrared Sensor (TIRS) data. We used various techniques like georeferencing, radiometric calibration, and atmospheric correction to examine land surface temperatures (LST) during the day and night. We focused on four types of natural land cover: water bodies, vegetation, built-up areas, and barren land. Interestingly, we noticed that water bodies had cooler temperatures during the day but got warmer at night, while vegetation was cooler at night and warmer during the day. To accurately spot areas with higher temperature anomalies, while filtering out colder spots due to sunlight, we overlaid daytime and nighttime LST data based on land cover types. Additionally, we used thematic maps from satellite images to pinpoint village areas. To doublecheck the anomalies we observed, we compared our findings with geological maps. Through this approach, we successfully identified nine distinct regions where temperatures were 3 to 6 degrees Kelvin higher than the normal background temperature. [ABSTRACT FROM AUTHOR]

The problem of this research stems from the fact that in Bihor County there are 75 localities that have one or more thermal water wells, of which only 8 locations can provide balneological treatment. The purpose of the research is to evaluate whether the geothermal potential of the region would be sustainable for the development of balneology in other localities as well. In order to meet the above-mentioned requirement, an interdisciplinary methodology was necessary, starting from geophysics and geology, including hydrogeology, chemistry, physics and ending with elements of tourism and balneological potential. The research methods refer to field work, the inventory of all locations that have geothermal resources, the creation of a database, the analysis of the stability and continuity over time of the source of thermalism, the analysis of the stability and time continuity of those physical-chemical properties that are suitable for balneology. In conclusion, out of the 67 locations that still cannot provide balneological treatment, only 20 could fulfil the sustainability criteria and are able to diversify the exploitation of thermal waters. There are 47 other locations that have unexploited boreholes, but despite this, we have come to the conclusion that balneology and tourism based on geothermal waters in Bihor County has a sustainable future in dozens of localities. [ABSTRACT FROM AUTHOR]

Link for citation: Krutenko D.S., Isaev V.I., Isaev S.G. Density of hydrocarbons and deep heat flow of the territory (southeast of Western Siberia). Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 7, рр. 148-163. In Rus. The relevance. According to the ruling theory for organic origin of petroleum, geothermal regime is considered to be the main factor, which is responsible for realization of potential for oil generation. Therefore, it is not irrelevant to develop geothermics as a method of exploration geophysics for forecasting and evaluating oil and gas potential. Forecast tasks are reduced to detection local geothermal anomalies and establishing its relation to hydrocarbon deposits. This method may make a good showing while supplementary exploration in the territories with well-developed infrastructure and a large amount of wells as it is based on modelling and analysing of available data and does not propose additional field works. The main aim: establishing qualitative and quantitative relations between deep heat flow and oil and gas potential, also between gradient zones of heat flow and localization of hydrocarbon fields in the west of Tomsk Region. Objects: thermal field and oil and gas potential in the west of Tomsk Region. Subjects. The thermal field is described with such parameters as deep heat flow density and horizontal gradient of heat flow. Hydrocarbon fields are divided depending on fluid type into oil, oil-gas-condensate and gas-condensate. Methods. The deep heat flow was determined through paleotemperature modelling. The grid with cells of 20×20 km was set on study territory in increments of 10 km. Heat flow values were determined in the centers of each cell using Kriging interpolation method. The absolute horizontal gradient of heat flow was calculated on the same grid using five spot formula. Quantitative parameter of oil and gas potential – hydrocarbon density – was determined on the same grid. Quantitative relations were investigated by correlation and regression analysis. Relationships of heat flow density and horizontal gradient of heat flow with localization of hydrocarbon fields of different fluid type were detected by one-way ANOVA test. Results. The main results of this study are established distribution patterns for deposits of different fluid type in thermal field. Correlation analysis showed highly significant correlation coefficients. The conclusion. Oil and oil-gas-condensate fields tend to the average heat flow values (52 mW/m2), while gas-condensate are associated with high heat flow values (57 mW/m2). The value of the absolute horizontal gradient of heat flow increases in row oil fields – oil-gas-condensate fields – gas-condensate fields. The difference between average values of gradient for all of field types is statistically significant. Therefore, we indicate appearance of geothermal quantitative criterion for forecasting fluid type of deposits in areas of high potential for hydrocarbons. Quantitative relation of high significance (r=0,53) between heat flow density and hydrocarbon density is established for high heat flow values (>56 mW/m2). Weak correlation (r=0,3) was indicated between horizontal gradient of heat flow and hydrocarbon density.

The assessment of geothermal potential has gained prominence among scholars, with a focus on establishing a reliable prediction model to reduce development risks. However, little attention has been given to predicting and evaluating the geothermal potential in Dali’s Eryuan area. This study introduces a novel hierarchical model integrating remote sensing, a Geographic Information System (GIS), and geophysics for the first-ever effective prediction of geothermal potential in Eryuan. The dataset includes lithology, seismic epicenter data, fault distribution, Bouguer gravity anomalies, SRTM-DEM images, and Landsat 8 remote sensing images. These datasets are converted into evidence maps and normalized to generate distinct evidence factor layers. Using the Analytic Hierarchy Process (AHP), a hierarchical model establishes weights for each evidence factor, resulting in a comprehensive prediction map. The results reveal the overall favorable geothermal potential in Eryuan, except the central area. Key hotspots include the Niujie–Sanying–Gromwell Lake and Liantie–Qiaohou, followed by the Youshou, Dengchuan, and Xixiang towns. Validation against known hot springs confirms the model’s accuracy and reliability.

Here, the geological factors controlling deep geothermal anomalies in mines were studied based on the geotemperature, lithologic thermal conductivity, and related geological data collected from the Qianjiaying Mine, China. A simulation of the change in magma waste heat, conducted using the ANSYS Workbench, revealed the distribution characteristics of geothermal anomalies in this mine and the corresponding geological control factors. The results revealed the following points. (1) First-degree heat hazard level (temperature = 31–37 ℃) occurred in the central and southwestern parts of the mine at an ~600-m depth, while second-degree heat hazard level (temperature ≥ 37 ℃) occurred at an ~800-m depth. The geotemperature and geothermal gradient in the southwestern part of the mine were anomalously high. (2) The geotemperatures measured in the mine generally reflected a standard increase with depth, while the geothermal gradient remained unchanged with depth. The geothermal gradient and its average value in the study area were 0.70–4.23 and 2.12 °C·hm−1, respectively. (3) A combination of stratum characteristics, geological structure, and groundwater characteristics led to geothermal anomalies in mines; additionally, the waste heat from magma had no significant effect on the geothermal field.

A mathematical model of the temperature field was constructed and the temperature values for hypsometric levels of 1000, 2000 and 3000 m were calculated. for these hypsometric levels, as well as a map of the isothermal surface +50 ºC. Working with this program involves the construction of digital models of the surface, ancillary operations with them and visualization of surfaces. The digital model of the surface has the form of values in the nodes of a rectangular regular grid, the dimension of which depends on the specific problem to be solved. The efficiency of the program of interpolation of two-dimensional functions is determined by the following aspects: a set of various interpolation methods; the ability of the researcher to control the various parameters of these methods; availability of means of an estimation of accuracy and reliability of the constructed surface; the opportunity to clarify the result based on the personal experience of the expert in view of various additional factors that could not be depicted as source data. It is confirmed that the patterns of distribution of the natural thermal field in the upper part of the earth’s crust are due to a number of reasons, the main of which are the lithological composition of rocks, features of tectonic structure and the nature of groundwater movement. As a result of the analysis of graphic constructions, a sharp decrease in the subsoil warming towards the Carpathian folded structure was witnessed. It has been scientifically proven that the subsoil warming within the Mukachevo basin is much higher than within the Solotvyno basin. The confinement of geothermal anomalies to zones of intensive development of deep faults has been confirmed mathematically and experimentally. Based on this feature, it can be argued that the presence of positive geothermal anomalies is a criterion of gas bearing capacity for predicting deposits within local defiection objects.

[Display omitted] • The position of the magma heat source was firstly reported in the city of Ruili. • Geothermal anomalies are distributed along NE–SW oriented faults. • The geothermal anomalies on the NE side exhibited greater significance. • Day-Night LST integration improves geothermal anomaly detection. Thermal infrared remote sensing (TIRS) technology is intriguing for geothermal anomaly detection due to its time efficiency and cost-effectiveness. Land surface temperature (LST) derived from TIRS indicates potential geothermal anomalies. However, LST on different natural features, exhibiting relatively cold/hot anomalies in daytime and nighttime, affected the identification of abnormal areas. The aim of this study was to highlight geothermal anomalous areas by integrating multi-view daytime and nighttime LST data. Specifically, the winter LST time series of drillings on 2013–2023 was processed based on Landsat-8 TIRS in diurnal scenarios. An information aggregation classification method about Dempster-Shafer evidence theory was presented to target recognition at nighttime by the ASTER LST product. This day-night information fusion analysis effectively highlighted potential areas with geothermal anomalies. The results demonstrated that the geothermal anomalies were mainly distributed along the Ruili-Longling Fault and Wanding Fault in a Northeast (NE) – Southwest (SW) direction, and the NE side was more significant than the SW side. These findings suggested that the east side was closer to the magma heat source, and the presumed magma heat source location aligned closely with the detected geothermal anomalies. Geological data were employed for geological interpretation of the LST anomaly area, eliminating non-geothermal influences. Along with drilling data verification, this method was successfully used to identify geothermal anomaly areas in Ruili City, Yunnan Province. Overall, this study provided valuable insights into the detection of geothermal anomalies through TIRS, contributing to the successful development of geothermal resources. [ABSTRACT FROM AUTHOR]

Many islands of the Aegean Sea show strong geothermal activity due to volcanism in the area. In this paper, Robust Satellite Techniques (RST) are used to isolate, from other known possible sources, those thermal anomalies possibly related to geothermal activity in the Miocene volcanic field of Lesvos Island (Northern Aegean). For this purpose, 12 years (2003–2014) of daily Night-time Land Surface Temperature (LST) products, from Moderate Resolution Imaging Spectroradiometer (MODIS) acquisitions were analyzed. The final dataset contained 770 thermal anomalies whose spatial correlation with geological and structural data of Lesvos - such as caldera rims, ring faults, major tectonic lineaments and hydrothermal alterations mapped by processing SENTINEL-2 MSI satellite images – has been particularly investigated. In the approximately 20 ma geothermal field of Lesvos, geothermal activity seems to be also associated with the extensional regime of the broader area that leads to lithosphere thinning and consequent heat transfer in the multi-fractured terrain of Lesvos through volcanic and tectonic faults. Achieved results seem to confirm the possibility to use RST-based thermal anomalies to identify temporal variations in the geothermal activity probably due to the uplifting and circulation of the hydrothermal waters.