Hydrochemical Characteristics of Geothermal Water

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Hydrogeology".

Deadline for manuscript submissions: closed (20 March 2023) | Viewed by 16692

Special Issue Editor


E-Mail Website
Guest Editor
Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Beijing, China
Interests: geothermal resources exploration and utilization
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Whether it is natural hot springs, geothermal wells, or jets in nature, etc., the chemical composition and isotopic composition of the fluids or gases they exude contain information about the material and energy inside the earth, indicating the geothermal geological conditions of the geothermal system, and are also closely related to engineering problems and environmental problems in the process of geothermal energy exploitation, such as fouling, corrosion, and greenhouse gas emissions, etc. Therefore, summarizing the geochemical technology developed for geothermal fluids in geothermics and geothermal fluid geochemistry is crucial to accelerate the promotion of clean geothermal energy development and utilization and promote energy conservation, emission reduction, and energy structure adjustment. To this end, a Special Issue of Water focusing on the "Hydrochemical Characteristics of Geothermal Water" will publish high-quality research on the application of fluid geochemical techniques in geothermal applications.

We have been invited by Water to be the Guest Editor, responsible for organizing and reviewing manuscripts for this Special Issue, and we welcome all colleagues to publish original research articles in this Special Issue.

Areas of research for this Special Issue include (but are not limited to) the following:

  • Application of isotope technology in geothermal exploration;
  • Water–rock interaction process and mechanism;
  • Application of hydrogeochemistry in geothermal exploration;
  • Application of gas geochemistry in geothermal exploration;
  • Application of rock geochemistry in geothermal exploration;
  • Geothermometer for geothermal reservoir temperatures estimation;
  • Geochemical characteristics of regional geothermal fluids
  • Sustainable Geothermal Development and Management.

Prof. Dr. Guiling Wang
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Water is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • geothermal isotope technology
  • water-rock interaction
  • hydrogeochemistry
  • gas geochemistry
  • gas geochemistry
  • geothermometer

Published Papers (15 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

16 pages, 9586 KiB  
Article
Simulation Study on Seepage Patterns of Geothermal Reinjection in Carbonate Thermal Reservoir and Geothermal Doublet Well Patterns in Xiong’an New Area
by Yong Qiao, Man Li, Li Du and Shaohua Li
Water 2023, 15(15), 2683; https://doi.org/10.3390/w15152683 - 25 Jul 2023
Cited by 1 | Viewed by 890
Abstract
The karst fissures of the carbonate thermal reservoir in Xiong’an New Area have developed, and they have the advantages of a concentrated distribution, shallow burial, large water volume, and easy recharge, which are conducive to the development and utilization of geothermal resources. This [...] Read more.
The karst fissures of the carbonate thermal reservoir in Xiong’an New Area have developed, and they have the advantages of a concentrated distribution, shallow burial, large water volume, and easy recharge, which are conducive to the development and utilization of geothermal resources. This paper took the carbonate thermal reservoir in Xiong’an New Area as the research object and studied the characteristics of the seepage patterns and temperature distribution in thermal storage with different well arrangements and recharge methods by laser etching the micromodel of the carbonate thermal reservoir and simulating the recharge methods. The paper established a numerical model of the resettlement area of Xiong’an New Area based on the production data and the current recharge well pattern, and it proposed a plan for a geothermal doublet well arrangement. The results showed that the injection speed and angle significantly influenced the seepage of injected water in the fractured reservoir. The injection speed correlated with the breakthrough time and swept area. The breakthrough time plummeted as the injection speed increased, and the swept area crept up as the injection-fracture dip increased. The well arrangements also impacted the seepage patterns. The well pattern of two injectors and three producers was relatively suitable for geothermal reinjection, and it was more appropriate to choose the maximum injection-fracture dip because of the largest swept area. Factors that affected the sustainable development and utilization of geothermal fields included the well pattern arrangement, well spacing, injection and production volumes, and the temperature of the injected water. Based on the modeling, it is recommended that the well spacing be greater than 500 m, and the injection and production volumes less than 110 m3/h in the resettlement area of Xiong’an New Area. Moreover, a vertical fracture well is recommended to reduce thermal breakthroughs. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

20 pages, 10829 KiB  
Article
Hydrochemistry of the Geothermal in Gonghe Basin, Northeastern Tibetan Plateau: Implications for Hydro-Circulation and the Geothermal System
by Shasha Liu, Xianchun Tang, Xiaomeng Han, Dailei Zhang and Guiling Wang
Water 2023, 15(11), 1971; https://doi.org/10.3390/w15111971 - 23 May 2023
Cited by 2 | Viewed by 1057
Abstract
The existence of high-temperature geothermal anomalies in the Gonghe Basin on the northeastern margin of the Tibetan Plateau has highlighted a new perspective on the geothermal system of the Himalayan-Tibetan Plateau orogen. In this study, we collected 32 groups of liquid and gas [...] Read more.
The existence of high-temperature geothermal anomalies in the Gonghe Basin on the northeastern margin of the Tibetan Plateau has highlighted a new perspective on the geothermal system of the Himalayan-Tibetan Plateau orogen. In this study, we collected 32 groups of liquid and gas samples from geothermal water, rivers, and boreholes in the Gonghe basin to analyze hydrochemistry, stable isotopes, and geochronology, which allow us to further reveal the geothermal fluid circulations of geothermal reservoirs. The ion contents of liquids identify two distinguished types of water, namely the Na-SO4-Cl type primarily from geothermal water and the Na-SO4-HCO3 and Na-Ca-CO3-SO4 types primarily from cold water. The compositions of the hydrogen and oxygen isotopes of the samples indicate geothermal waters were recharged by atmospheric precipitation and 3000–4600 m high snow mountain meltwater, which may have experienced circulation of 16,300–17,300 years and mixtures of submodern and recent recharge water sources evidenced by isotopes of 3H, 13C, and 14C data. The 3He/4He ratios of these geothermal waters varying from 0.03 to 0.84 Ra further highlighted a crustal-dominated heat source in the region. The deep thermal reservoir temperature in the Gonghe Basin at 160 ± 10 °C and the depth of circulation of geothermal water is 2200–2500 m. Based on this evidence, we have established a geothermal fluid circulation model and refined the exchange processes of fluids and geothermal heat, further enriching the details of the geothermal system in Gonghe Basin. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

15 pages, 4167 KiB  
Article
Improvement in Operation Efficiency of Shallow Geothermal Energy System—A Case Study in Shandong Province, China
by Qinghua Wu, Yue Fan and Xiao Wang
Water 2023, 15(7), 1409; https://doi.org/10.3390/w15071409 - 05 Apr 2023
Cited by 1 | Viewed by 1493
Abstract
Shallow geothermal energy (SGE) is a renewable energy source that has the advantage of being low-cost, clean, and locally sourced compared to fossil fuels, and is thus significant for China to achieve its future goals of carbon peaking and carbon neutrality. However, determining [...] Read more.
Shallow geothermal energy (SGE) is a renewable energy source that has the advantage of being low-cost, clean, and locally sourced compared to fossil fuels, and is thus significant for China to achieve its future goals of carbon peaking and carbon neutrality. However, determining how to improve the operational efficiency of SGE systems is a key factor in the sustainable development and utilization of geothermal energy. This study examined the long-term operational efficiency of SGE systems and applied numerical simulation methods of hydro-thermal coupling to a SGE utilization project in Shandong Province, China. The effect of the distribution of pumping and injection wells on the operation efficiency of the SGE system was analyzed, and the parameter of operation efficiency, defined by the ratio of the practical minable shallow geothermal energy to the theoretical shallow geothermal energy, was applied to quantify the operation efficiency of the SGE system. The simulated results show that the phenomenon of heat transfixion is significant in the current operation scheme, where one of three pumping wells is located downstream of the study area, which indicates that the local groundwater flow field mainly controls the operation efficiency of the SGE system. In the optimized operation scheme, the distribution of pumping and injection wells can be adjusted according to the feature of groundwater flow and temperature fields. The degree of heat transfixion significantly declines and the operation efficiency increases by 71.5%. In addition, further improvements in the operational efficiency of the SGE system can be considered through the running time. The findings of this paper will be useful for the construction and management of SGE systems. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

21 pages, 3953 KiB  
Article
Determination of Reservoir Temperatures of Low-Enthalpy Geothermal Systems in the Sudetes (SW Poland) Using Multicomponent Geothermometers
by Barbara Kiełczawa
Water 2023, 15(3), 422; https://doi.org/10.3390/w15030422 - 20 Jan 2023
Viewed by 1524
Abstract
Thermal waters from deep circulation systems are mixed with cold shallow system components during their ascent to drainage zones. In the current research, classic chemical geothermometers and geothermometric modeling using the GeoT app were employed to determine the temperatures of geothermal reservoirs in [...] Read more.
Thermal waters from deep circulation systems are mixed with cold shallow system components during their ascent to drainage zones. In the current research, classic chemical geothermometers and geothermometric modeling using the GeoT app were employed to determine the temperatures of geothermal reservoirs in the Sudetic region. Moreover, models of primary deep components mixed with cold shallow circulation system components were used to determine their proportions, particularly water deposits. In the studied geothermal systems, the proportion of the cold component ranged from c. 46% to c. 75%. Classic cation thermometers (Na-K, Na-K-Ca) indicated a very wide temperature range and they proved rather unreliable. The reservoir temperatures estimated with silica thermometers ranged from 52 °C to 141 °C and they can be deemed more reliable. The temperatures obtained from modeling (54.5 ± 3–120 ± 4) were adopted as temperatures of waters pre-cooled conductively and then mixed with cold components. The temperatures of primary deep waters (74–225 °C) were adopted as geothermal system temperatures. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

23 pages, 5110 KiB  
Article
Analysis of the Formation Mechanism of Medium and Low-Temperature Geothermal Water in Wuhan Based on Hydrochemical Characteristics
by Zhibin Yin, Xuan Li, Changsheng Huang, Wei Chen, Baoquan Hou, Xiaozhe Li, Wenjing Han, Pingping Hou, Jihong Han, Chonghe Ren, Jin Zou, Shan Hua, Liansan Xu and Ziliang Zhao
Water 2023, 15(2), 227; https://doi.org/10.3390/w15020227 - 05 Jan 2023
Cited by 2 | Viewed by 1376
Abstract
Wuhan and its surrounding areas have obvious geothermal spring outcrops, which are unexplored potential geothermal resources. The degree of geothermal resource development in Wuhan is low, and there is a lack of systematic research on their hydrochemical characteristics and formation mechanism. The Wuhan [...] Read more.
Wuhan and its surrounding areas have obvious geothermal spring outcrops, which are unexplored potential geothermal resources. The degree of geothermal resource development in Wuhan is low, and there is a lack of systematic research on their hydrochemical characteristics and formation mechanism. The Wuhan area is bounded by the Xiang-Guang fault, the South Qinling-Dabie orogenic belt in the north, and the Yangtze landmass in the south, with Silurian and Quaternary outcrops and little bedrock outcrops. The Silurian is the main water barrier in the region, which separates the upper Triassic and Paleogene as shallow aquifers and the lower Cambrian and Ordovician as deep aquifers. Different strata are connected by a series of fault structures, which constitute Wuhan’s unique groundwater water-bearing system. Eleven geothermal water (23~52 °C) and six surface water samples (around 22 °C) were collected from the study area. The geothermal water in the study area is weakly alkaline, with a pH of 7.04~8.24. The chemical type of geothermal water is mainly deep SO42− with a higher TDS and shallow HCO3 type water with a lower TDS. Isotopic analysis indicates that atmospheric precipitation and water-rock interaction are the main ionic sources of geothermal water. The chemical composition of geothermal water is dominated by ion-exchange interactions and the dissolution of carbonates and silicates. The characteristic coefficients, correlation analysis, water chemistry type, recharge elevation, geothermal water age, reservoir temperature, and cycle depth were also analyzed. The performance was similar in the same geothermal reservoir, which could be judged as an obviously deep and shallow geothermal fluid reservoir, and the genetic conceptual model of Wuhan geothermal was preliminarily deduced. DXR-8 and DXR-9 had the best reservoir conditions, hydrodynamic conditions, rapid alternation of water bodies, and large circulation depth, which is a favorable location for geothermal resource development and will bring considerable economic and social benefits. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

21 pages, 3786 KiB  
Article
Genesis of Significance of Carbonated Thermal Water Springs in Xining Basin, China
by Yude Lei, Zhen Zhao, Baojian Zhang, Xianchun Tang, Yinfei Luo, Guiling Wang, Jun Gao and Dailei Zhang
Water 2022, 14(24), 4058; https://doi.org/10.3390/w14244058 - 12 Dec 2022
Cited by 3 | Viewed by 1545
Abstract
There are 30 carbonate hot springs in Yaoshuitan geothermal field, Xining Basin, China, with a temperature of 18~41.5 °C; and there are 10 carbonate hot springs in Qijiachuan geothermal field, with a temperature of 10~19.5 °C. Both geothermal fields are carbonate hot springs [...] Read more.
There are 30 carbonate hot springs in Yaoshuitan geothermal field, Xining Basin, China, with a temperature of 18~41.5 °C; and there are 10 carbonate hot springs in Qijiachuan geothermal field, with a temperature of 10~19.5 °C. Both geothermal fields are carbonate hot springs containing large amounts of CO2 gas. In order to reveal the origin of the carbonated hot springs in Yaoshuitan and Qijiachuan of Xining Basin, this paper offers a comprehensive study of the regional deep geology, tectonic setting, total analysis of carbonated hot springs, δ2H, δ18O, δ13C isotopes, main gas composition, and geochemical characteristics of travertine dating, travertine δ13C, and rare earth elements. The geological process of carbonated hot spring formation and the evolution of H+ content from deep to shallow is revealed, and the genetic mechanism of the carbonated hot spring in Xining Basin is systematically summarized. The results show that: (1) The characteristics of δ2H and δ18O isotopes indicate that the recharge source of carbonated thermal water springs in Xining Basin is mainly atmospheric precipitation. The age of carbonated thermal water springs at 14C is more than 20 ka, indicating that some of them may come from deep fluid (gas) sources. The R/Ra in carbonated thermal water springs is mostly less than 1, indicating that the helium in geothermal water is mainly crustal source helium, and there is no deep mantle source material. (2) The Piper three-plot indicates that the direction of groundwater evolution from the recharge area at the edge of Xining Basin to Yaoshuitan and Qijiachuan carbonated thermal water spring area near the edge of the basin is opposite to the normal path of groundwater evolution in the basin, which is due to the large amount of CO2 gas mixed in the deep fault along the northern margin of Laji Mountain. The ratio of (Ca2+ + Mg2+) and (HCO3 + SO42−) in the Potan and Qijiachuan carbonated thermal water springs is close to 1, and the ratio of (Na+ + K+)/HCO3 is less than 1. It indicates that the chemical composition of the Yaoshuitan carbonated thermal water spring and the Qijiachuan carbonated thermal water spring in Xining Basin is dominated by the dissolution of calcite, dolomite, and gypsum in deep carbonate reservoirs, supplemented by the dissolution of silicate minerals. The relationship between the volume fraction of CO2 and the δ13C value of carbon isotope of CO2 indicates that the source of CO2 is inorganic, which is mainly formed by metamorphism and decomposition of deep carbonate and marble. The δEu < 1 and δCe > 1 of the rare earth elements in the calcium center of the carbonated thermal water springs indicate that the groundwater supplying the travertine material has been in the acidic environment receiving CO2 from the deep crust for a long time. (3) A series of tectonic activities, such as late collision and post-collision between the Indian and Eurasian plates, has led to the uplift, asthenosphere upwelling, and thermal invasion of the northern Tibetan Plateau and other deep dynamic processes. The deep faults in the northern margin of the Laji Mountain and other deep faults with obvious neotectonic activity have provided channels for the up-invasion of deep thermal materials, and local geothermal anomalies were formed near the deep faults. The hidden carbonate rocks and silicate rocks with large thickness undergo thermal metamorphism under high temperature and high pressure in the deep geothermal anomaly area and form a large amount of CO2, which is dissolved in water and enhances the acidity of water. At the same time, the dissolution reaction of acidic water to carbonate rocks consumes H+, which keeps the carbonated thermal water spring weakly acidic. (4) The composition of travertine in carbonated thermal water springs is dominated by calcite, indicating that travertine may be formed in a deep geological environment with a temperature of 150~200 °C, indicating that there are abnormal heat sources in shallow carbonate strata with a burial depth of 3000~4000 m. The abnormal heat source may be caused by the deep fault in the northern margin of Laji Mountain, as well as other deep and large faults channeled in the deep crust and mantle heat source, indicating that the deep fault in the northern margin of Laji Mountain has an obvious heat-controlling effect, and there is a good prospect of geothermal resources exploration near the fault. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

22 pages, 8160 KiB  
Article
Genesis Mechanisms of Geothermal Resources in Mangkang Geothermal Field, Tibet, China: Evidence from Hydrochemical Characteristics of Geothermal Water
by Yuzhong Liao, Yanguang Liu, Guiling Wang, Tingxin Li, Feng Liu, Shuaichao Wei, Xiaoxue Yan, Haonan Gan and Wei Zhang
Water 2022, 14(24), 4041; https://doi.org/10.3390/w14244041 - 11 Dec 2022
Cited by 3 | Viewed by 1453
Abstract
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

20 pages, 8854 KiB  
Article
A Joint Method Based on Geochemistry and Magnetotelluric Sounding for Exploring Geothermal Resources in Sedimentary Basins and Its Application
by Yanguang Liu, Guiling Wang, Xuezhong Guo, Jing Hu, Jianguo Wang, Xiaojun Wang and Gui Zhao
Water 2022, 14(20), 3299; https://doi.org/10.3390/w14203299 - 19 Oct 2022
Cited by 1 | Viewed by 1625
Abstract
The precise exploration of the characteristics of geothermal fields in sedimentary basins, such as the temperature and burial depth of their deep geothermal reservoirs, is of great significance for improving the probability of penetration and reducing exploration risks and development costs. This study [...] Read more.
The precise exploration of the characteristics of geothermal fields in sedimentary basins, such as the temperature and burial depth of their deep geothermal reservoirs, is of great significance for improving the probability of penetration and reducing exploration risks and development costs. This study proposed a joint exploration method combining magnetotelluric (MT) sounding and geothermometers. Using this method, this study estimated the geothermal reservoirs’ temperature and the circulation depth of geothermal water in the Xianxian geothermal field, a typical geothermal field in a large sedimentary basin in northern China, and prepared the temperature and depth maps of the geothermal reservoirs. The main results are as follows. First, the bedrock’s geothermal reservoirs with karst fissures in the Xianxian geothermal field have great potential for development. Among them, geothermal reservoirs in the Jixianian Wumishan formation have a top depth of 1100–1500 m and a thickness of 700–1700 m, and the geothermal reservoirs in the Jixianian Gaoyuzhuang formation have a top depth of 3700–4000 m and a maximum drilled thickness of 400 m. The geothermal reservoirs of the Xianxian geothermal field mainly have medium and low temperatures of 138–160 °C and the circulation depth of the geothermal water is 5873 m. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

17 pages, 4797 KiB  
Article
Temperature Estimation of a Deep Geothermal Reservoir Based on Multiple Methods: A Case Study in Southeastern China
by Wenjing Lin and Xiaoxiao Yin
Water 2022, 14(20), 3205; https://doi.org/10.3390/w14203205 - 12 Oct 2022
Cited by 6 | Viewed by 1818
Abstract
Estimating deep geothermal reservoir temperatures is an essential mission of geothermal exploration and development. The thermal reservoir temperature estimated directly using geothermometry without comparative analysis is often far from the actual temperature. In this paper, taking the typical geothermal systems in the Xiamen [...] Read more.
Estimating deep geothermal reservoir temperatures is an essential mission of geothermal exploration and development. The thermal reservoir temperature estimated directly using geothermometry without comparative analysis is often far from the actual temperature. In this paper, taking the typical geothermal systems in the Xiamen Island–Zhangzhou area of southeastern China as an example, different methods such as a water–rock equilibrium analysis, SiO2 geothermometer, multi-mineral equilibrium diagram, and silica-enthalpy mixing model are used to make a quantitative and qualitative analysis of the chemical equilibrium of minerals and fluids in the geothermal system. Finally, the applicability of different methods was compared and analyzed, and the geothermal reservoir temperature was estimated using the appropriate method. The results show that the calculated results of the Si-enthalpy mixing model of a typical geothermal system in southeastern China are significantly high. At the same time, the SiO2 geothermometer (without vapor loss), which is closest to the results of the multi-mineral equilibrium diagram, was chosen as the geothermal reservoir temperature of the geothermal system in the study area. This study can provide a reference for the future selection of methods of deep geothermal reservoir temperature estimation in similar areas. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

18 pages, 6992 KiB  
Article
Geochemical Characteristics of Geothermal Fluids of a Deep Ancient Buried Hill in the Xiong’an New Area of China
by Mingxiao Yu, Guiling Wang, Feng Ma, Wei Zhang, Wenjing Lin, Xi Zhu and Hanxiong Zhang
Water 2022, 14(19), 3182; https://doi.org/10.3390/w14193182 - 10 Oct 2022
Cited by 2 | Viewed by 1607
Abstract
The Xiong’an New Area is one of the areas with the richest geothermal resources in the east-central part of China. However, the genesis of the geothermal water in Jixianian carbonate reservoirs in this area is still unclear. This study conducted systematical geochemical and [...] Read more.
The Xiong’an New Area is one of the areas with the richest geothermal resources in the east-central part of China. However, the genesis of the geothermal water in Jixianian carbonate reservoirs in this area is still unclear. This study conducted systematical geochemical and isotopic analyses of the geothermal water in the Jixianian carbonate reservoirs in the Rongcheng geothermal field and summed up the genetic mechanisms of geothermal fluids in deep geothermal reservoirs. The results are as follows: the geothermal water in the study area has a hydrochemical type of Cl·HCO3-Na and originates from meteoric water in the Taihang Mountains. The age of the geothermal water increases from 22 ka in the west to 45 ka in the east, and its transport rate is approximately 1.02 m/a. The Sr concentration and 87Sr/86Sr ratio of the geothermal fluids increase along their runoff direction and are related to the dissolution and filtration of minerals such as dolomite and gypsum and the decay of 87Rb in the Earth’s crust. The geothermal water is involved in deep circulation and occurs in a closed system. These results are consistent with those obtained using the PHREEQC inverse model. The reverse hydrogeochemical simulation results exhibited the precipitation of gypsum and halite, the dissolution of anorthite and quartz, and desulfurization. The geothermal reservoir temperatures were estimated to be 92–113 °C using a SiO2 geothermometer, and the thermal groundwater may have undergone deep circulation, with a prolonged retention time. Moreover, the groundwater occurs in a closed environment, strong water-rock interactions occur between the groundwater and related minerals, and the groundwater absorbs the heat from the deep heat source, thus forming geothermal water. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

19 pages, 8061 KiB  
Article
Mineral Reaction Kinetics during Aciding of the Gaoyuzhuang Carbonate Geothermal Reservoir in the Xiong’an New Area, Northern China
by Gaofan Yue, Xi Zhu, Guiling Wang and Feng Ma
Water 2022, 14(19), 3160; https://doi.org/10.3390/w14193160 - 07 Oct 2022
Viewed by 1222
Abstract
There are abundant geothermal resources in the Xiong’an New Area, China. Drilling has revealed a greater potential in the deep Gaoyuzhuang geothermal reservoir. However, the reservoir required acidification to increase its water production. In this study, three types of core samples with different [...] Read more.
There are abundant geothermal resources in the Xiong’an New Area, China. Drilling has revealed a greater potential in the deep Gaoyuzhuang geothermal reservoir. However, the reservoir required acidification to increase its water production. In this study, three types of core samples with different mineral compositions from different depths in the target boreholes were selected for acid rock reaction experiments at the temperature of 40 °C, 60 °C, 80 °C and 100 °C, and pressure of 30 MPa. The kinetics of the acid rock reaction of the major minerals were modeled based on the transitional state theory. The kinetic parameters were obtained by comparing the modelling and experimental results. The results show that the lithology of the Gaoyuzhuang reservoir is primarily dolomite. The dissolution ratio for 15 wt.% HCl reached 84.1% on average for the rock fragments. Temperature has a significant effect on the dissolution rate of the minerals. In the presence of HCl (acidic mechanism), the reaction rate constants of the dolomite, calcite and illite reached 2.4 × 10−4 mol/m2/s, 5.3 × 10−1 mol/m2/s and 9.5 × 10−2 mol/m2/s, respectively. The results of this study provide the basic parameters for the design and evaluation of field acidizing. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

19 pages, 4720 KiB  
Article
Geochemical Composition, Source and Geothermometry of Thermal Water in the Bugok Area, South Korea
by Chanho Jeong, Yujin Lee, Yongcheon Lee, Sangwon Ahn and Keisuke Nagao
Water 2022, 14(19), 3008; https://doi.org/10.3390/w14193008 - 24 Sep 2022
Cited by 1 | Viewed by 1566
Abstract
Thermal water from the hot springs around Bugok, South Korea, has the highest discharge temperature (78 °C), and the source of that heat is of primary interest. The key 3He/4He ratio runs along a single air-mixing line between the mantle [...] Read more.
Thermal water from the hot springs around Bugok, South Korea, has the highest discharge temperature (78 °C), and the source of that heat is of primary interest. The key 3He/4He ratio runs along a single air-mixing line between the mantle and the crust, with the latter accounting for 97.0–97.3%. This suggests that the thermal source is radioactive decay in granodiorite, rock that intruded beneath the Cetaceous era sedimentary rock. Thermal water containing Na–HCO3 (SO4) evolved geochemically from stream water and groundwater containing Ca–HCO3. With respect to δ34S, there are two types of thermal water: low temperature with low δ34S (−3.00~+1.00‰), and high temperature with high δ34S (+4.60~+15.0‰), which is enriched by the kinetic fractionation of H2S. The thermal water samples, except for a few, reached partial chemical equilibrium. The thermal reservoir temperatures were estimated as in the range of 90–126 °C by the K–Mg geothermometer of Giggenbach and the thermodynamic equilibrium of quartz and muscovite. This study suggests a conceptual model for the formation of geothermal water, including the thermal reservoir in the Bugok area. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

17 pages, 4885 KiB  
Article
Effect of Temperature and Acidification on Reinjection of Geothermal Water into Sandstone Geothermal Reservoirs: Laboratory Study
by Haonan Gan, Zhiming Liu, Xiao Wang, Yu Zhang, Yuzhong Liao, Gui Zhao, Jichu Zhao and Zhitao Liu
Water 2022, 14(19), 2955; https://doi.org/10.3390/w14192955 - 21 Sep 2022
Cited by 4 | Viewed by 1433
Abstract
Geothermal reinjection is a new method of geothermal development which can maintain regional geothermal reservoir pressure, and it is conducive to the sustainable development and utilization of geothermal heat. However, geothermal reinjection blockage has always been a problem that restricts geothermal development and [...] Read more.
Geothermal reinjection is a new method of geothermal development which can maintain regional geothermal reservoir pressure, and it is conducive to the sustainable development and utilization of geothermal heat. However, geothermal reinjection blockage has always been a problem that restricts geothermal development and utilization, causing geothermal reservoirs, especially the attenuation of sandstone geothermal reservoirs. Considering an example of a typical sandstone geothermal reservoir in Binzhou, in this study, in situ geothermal fluids and borehole cores were collected to conduct automatic rotary reactor experiments under different temperature and acidification conditions in laboratory studies. The chemical compositions of geothermal fluids and core samples before and after the experiment were compared. The results show that both temperature and acid have significant effects on the water–rock interaction. The effect of temperature is mainly shown on mineral solubility, while the effect of acidification is shown in the increased dissolution of calcite and feldspar minerals. Compared with high temperature (65 °C) reinjection conditions, the calcite precipitation at a low temperature (45 °C) is largely reduced, but with larger total mineral volume changes, mainly due to the formation of montmorillonite. Therefore, from the laboratory studies, it is recommended to preform reinjection using a low-temperature fluid, without adding acids. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

17 pages, 2422 KiB  
Article
The Estimation of Geothermal Reservoir Temperature Based on Integrated Multicomponent Geothermometry: A Case Study in the Jizhong Depression, North China Plain
by Junzu Deng, Wenjing Lin, Linxiao Xing and Li Chen
Water 2022, 14(16), 2489; https://doi.org/10.3390/w14162489 - 12 Aug 2022
Cited by 13 | Viewed by 1989
Abstract
The coal-dominated energy structure in the Beijing–Tianjin–Hebei region has caused serious air pollution and contradicts the construction of a clean, low-carbon, safe and efficient energy system. Substituting geothermal energy for fossil energy such as coal can effectively alleviate this problem. Located in the [...] Read more.
The coal-dominated energy structure in the Beijing–Tianjin–Hebei region has caused serious air pollution and contradicts the construction of a clean, low-carbon, safe and efficient energy system. Substituting geothermal energy for fossil energy such as coal can effectively alleviate this problem. Located in the hinterland of the Beijing-Tianjin-Hebei region, the Jizhong Depression is rich in geothermal resources and has great development potential, though the degree of current development and utilization is not high. Vigorously developing geothermal energy can not only effectively alleviate the air pollution problem in the Beijing–Tianjin–Hebei region, but also optimize the regional energy structure. Geothermal reservoir temperature determines the development and utilization value of geothermal resources, and accurate evaluation of the geothermal reservoir temperature of geothermal resources can provide a reliable basis for the subsequent development of geothermal resources in the Jizhong Depression. Aiming at the commonly used sandstone geothermal reservoir and carbonate geothermal reservoir in the Jizhong Depression, this paper collected 24 sandstone geothermal reservoir geothermal fluids and 14 carbonate geothermal reservoir geothermal fluids in the central-southern area of the Jizhong Depression and a water chemistry test was carried out. According to the test results of water chemistry, the temperature of the geothermal reservoir is estimated by using the cation geothermometer, the SiO2 geothermometer and the multi-mineral equilibrium method, and it is compared with the actual temperature measurement results of the boreholes. The results show that the direct use of a geothermal geothermometer for calculation will cause large errors. Through water–rock balance analysis, the use of a Na-K-Mg balance diagram, SiO2 and 1000/T relationship diagram and Na/K and 1000/T relationship diagram can determine whether the geothermal fluid is suitable for the geothermometer, which can effectively reduce the error. The chalcedony geothermometer in the central and southern part of the Jizhong Depression is the most suitable. The multi-mineral balance method, the Na-K geothermometer and the K-Mg geothermometer have also achieved good results, while the quartz and Na-K-Ca geothermometers are not suitable for the south-central Jizhong Depression area. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

24 pages, 8172 KiB  
Article
Characteristics of the Rongcheng Bulge Geothermal Field and the Evolution of Geothermal Fluids, Xiong’an New Area, China
by Hanxiong Zhang, Guiling Wang, Wei Zhang, Feng Ma, Xi Zhu, Gaofan Yue and Mingxiao Yu
Water 2022, 14(16), 2468; https://doi.org/10.3390/w14162468 - 10 Aug 2022
Cited by 2 | Viewed by 1562
Abstract
The study of geothermal field characteristics and the mechanisms involved in the hydrogeochemical evolution of geothermal fluids is an effective means to understand the formation, reservoir conditions and circulation mechanics of geothermal resources. Documenting these parameters within the Rongcheng Bulge of Xiong’an New [...] Read more.
The study of geothermal field characteristics and the mechanisms involved in the hydrogeochemical evolution of geothermal fluids is an effective means to understand the formation, reservoir conditions and circulation mechanics of geothermal resources. Documenting these parameters within the Rongcheng Bulge of Xiong’an New Area, China, is of great significance to its future development and utilization as a geothermal resource. In this paper, we investigate the hydrochemical characteristics of geothermal fluids and the rock thermal properties of the Rongcheng Bulge Reservoir and the surrounding rocks to identify the mechanisms of geothermal fluid genesis within the geothermal field. The results show that the geothermal water in the Rongcheng Bulge is mainly recharged by atmospheric rainfall. The thermal storage temperature at which the deep geothermal fluid is located ranges between 63 and 105 °C, whereas the depth of geothermal water circulation is between 1500 and 2700 m. Fluid exchange is weak during deep circulation, but as the geothermal fluid rises, the proportion of cold water mixed with the geothermal waters is 75–95%. The overall geothermal gradient of the carbonate thermal reservoir is significantly lower than that within the overburden and basement rocks, probably due to convection during the upward transport of groundwater in the reservoir. The geothermal fluid in the area of the Rongcheng Bulge is recharged by the Taihang Mountains and atmospheric precipitation. Following recharge and deep circulation, the fluids rise along fractures and by interlayer convection and are mixed with cold water to form the current, accessible geothermal water. Full article
(This article belongs to the Special Issue Hydrochemical Characteristics of Geothermal Water)
Show Figures

Figure 1

Back to TopTop