Hydrochemical characteristics and evolution of geothermal waters in the eastern Himalayan syntaxis geothermal field, southern Tibet

Geothermics ◽  
2021 ◽  
Vol 97 ◽  
pp. 102233
Author(s):  
Xiao Li ◽  
Jihong Qi ◽  
Lei Yi ◽  
Mo Xu ◽  
Xiaoyu Zhang ◽  
...  
Keyword(s):  
Geothermal Field ◽  
Hydrochemical Characteristics ◽  
Southern Tibet ◽  
Geothermal Waters ◽  
Eastern Himalayan Syntaxis

scholarly journals Hydrochemical Characteristics and Evolution of Geothermal Fluids in the Chabu High-Temperature Geothermal System, Southern Tibet

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
X. Wang ◽  
G. L. Wang ◽  
H. N. Gan ◽  
Z. Liu ◽  
D. W. Nan
Keyword(s):  
High Temperature ◽  
Research Area ◽  
Geothermal Field ◽  
Geothermal System ◽  
Hydrochemical Characteristics ◽  
Mixing Processes ◽  
Southern Tibet ◽  
Geothermal Waters ◽  
South Central ◽  
Geothermal Fluids

This study defines reasonable reservoir temperatures and cooling processes of subsurface geothermal fluids in the Chabu high-temperature geothermal system. This system lies in the south-central part of the Shenzha-Xietongmen hydrothermal active belt and develops an extensive sinter platform with various and intense hydrothermal manifestations. All the geothermal spring samples collected systematically from the sinter platform are divided into three groups by cluster analysis of major elements. Samples of group 1 and group 3 are distributed in the central part and northern periphery of the sinter platform, respectively, while samples of group 2 are scattered in the transitional zone between groups 1 and 3. The hydrochemical characteristics show that the geothermal waters of the research area have generally mixed with shallow cooler waters in reservoirs. The reasonable reservoir temperatures and the mixing processes of the subsurface geothermal fluids could be speculated by combining the hydrochemical characteristics of geothermal springs, calculated results of the chemical geothermometers, and silica-enthalpy mixing models. Contour maps are applied to measured emerging temperatures, mass flow rates, total dissolved solids of spring samples, and reasonable subsurface temperatures. They indicate that the major cooling processes of the subsurface geothermal fluids gradually transform from adiabatic boiling to conduction from the central part to the peripheral belt. The geothermal reservoir temperatures also show an increasing trend. The point with the highest reservoir temperature (256°C) appears in the east-central part of the research area, which might be the main up-flow zone. The cooling processes of the subsurface geothermal fluids in the research area can be shown on an enthalpy-chloride plot. The deep parent fluid for the Chabu geothermal field has a Cl− concentration of 290 mg/L and an enthalpy of 1550 J/g (with a water temperature of 369°C).

scholarly journals Hydrogeochemical Characteristics and Genesis of Geothermal Water from the Ganzi Geothermal Field, Eastern Tibetan Plateau

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1631
Author(s):  
Fan ◽  
Pang ◽  
Liao ◽  
Tian ◽  
Hao ◽  
...  
Keyword(s):  
High Temperature ◽  
Tibetan Plateau ◽  
Heat Source ◽  
Chloride Concentration ◽  
Geothermal Field ◽  
Geothermal Water ◽  
Helium Isotope ◽  
Geothermal System ◽  
The Tibetan Plateau ◽  
Geothermal Waters

The Ganzi geothermal field, located in the eastern sector of the Himalayan geothermal belt, is full of high-temperature surface manifestations. However, the geothermal potential has not been assessed so far. The hydrochemical and gas isotopic characteristics have been investigated in this study to determine the geochemical processes involved in the formation of the geothermal water. On the basis of δ18O and δD values, the geothermal waters originate from snow and glacier melt water. The water chemistry type is dominated by HCO3-Na, which is mainly derived from water-CO2-silicate interactions, as also indicated by the 87Sr/86Sr ratios (0.714098–0.716888). Based on Cl-enthalpy mixing model, the chloride concentration of the deep geothermal fluid is 37 mg/L, which is lower than that of the existing magmatic heat source area. The estimated reservoir temperature ranges from 180–210 °C. Carbon isotope data demonstrate that the CO2 mainly originates from marine limestone metamorphism, with a fraction of 74–86%. The helium isotope ratio is 0.17–0.39 Ra, indicating that the He mainly comes from atmospheric and crustal sources, and no more than 5% comes from a mantle source. According to this evidence, we propose that there is no magmatic heat source below the Ganzi geothermal field, making it a distinctive type of high-temperature geothermal system on the Tibetan Plateau.

Boron geochemistry of the geothermal waters from two typical hydrothermal systems in Southern Tibet (China): Daggyai and Quzhuomu

Geothermics ◽  
2019 ◽  
Vol 82 ◽  
pp. 190-202 ◽  
Author(s):  
Mingliang Liu ◽  
Qinghai Guo ◽  
Geng Wu ◽  
Wei Guo ◽  
Weiyu She ◽  
...  
Keyword(s):  
Hydrothermal Systems ◽  
Southern Tibet ◽  
Geothermal Waters

Acid-sulphate hydrothermal alteration of andesitic tuffs and genesis of halloysite and alunite deposits in the Biga Peninsula, Turkey

Clay Minerals ◽  
2008 ◽  
Vol 43 (2) ◽  
pp. 281-315 ◽  
Author(s):  
Ö. I. Ece ◽  
P. A. Schroeder ◽  
M. J. Smilley ◽  
J. M. Wampler
Keyword(s):  
Hydrothermal Alteration ◽  
Volcanic Rocks ◽  
Geothermal Field ◽  
Parent Material ◽  
Thermal Waters ◽  
Geothermal Waters ◽  
Biga Peninsula ◽  
The North ◽  
Clay Deposits ◽  
Nw Turkey

AbstractThe Biga Peninsula of NW Turkey is host to six major halloysite deposits in the Go¨nen, Yenice and Balya districts. Mineralization took place in areas of Permian limestone blocks where the Triassic Karakaya Complex is in contact with early Miocene calc-alkaline volcanic rocks. Hypogene halloysite mineralization was controlled by the intersection of minor faults in the vicinity of clay deposits. During the Pleistocene, activity of the North Anatolian Fault (NAF) brought ascending geothermal solutions through the fault zones to the surface, which led to hydrothermal alteration and halloysite formation. N-MORB normalized element values for each halloysite deposit and the volcanic rocks suggest genetic links. Alunite and halloysite were formed in the Turplu area where upwelling hydrothermal waters contained major H2S and SO2acids. Only halloysite mineralization occurred in outflow areas of the same fossil geothermal field.Pyrite and alunite samples from the Turplu deposits have δ34S values of 0.6–1.8% and 4.8–7.9%, respectively, with values for gypsum of 3.1–3.5%. The δ34S values of pyrite suggest that local meteoric waters had partially mixed with the dominant fluid during the closure stage of fossil hydrothermal activities. The range of δD values of halloysite samples from Turplu is –58.4 to –68.6%. The δ18O values for halloysite are in the range 16.7–18.1%. All halloysite deposits in the study areas are either overlying or adjacent to limestone blocks, and these provide excellent drainage for the discharging geothermal waters. Subsurface drainage systems in the karstic environment and the SO2-bearing thermal waters indicate the importance of acidic waters and the continuous leaching of elements in forming relatively pure hydrated halloysite. A steam-heated dissolution-precipitation model is proposed for the occurrence of all halloysite and alunite deposits. Sulphur gases (H2S-SO2) of hypogene origin rose from deep in the fault zone to the surface where they encountered oxygenated groundwater at the water table. The occurrence of H2SO4in this hydrothermal system enhanced the acidity of geothermal waters provoking advanced argillic alteration. Hypogene alunite deposits also have large P2O5contents, suggesting a parent material with a magmatic origin deeper than the alkaline tuffs. Halloysite is a fast-forming metastable precursor to kaolinite.

scholarly journals Hydrogeochemical Characteristics and Geothermometry Applications of Thermal Waters in Coastal Xinzhou and Shenzao Geothermal Fields, Guangdong, China

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-24 ◽  
Author(s):  
Xiao Wang ◽  
Guoping Lu ◽  
Bill X. Hu
Keyword(s):  
Thermal Water ◽  
Coastal Region ◽  
Geothermal Field ◽  
Thermal Waters ◽  
Isotopic Data ◽  
Geothermal Waters ◽  
Cross Sectional ◽  
Geothermal Fields ◽  
Granite Batholith

Two separate groups of geothermal waters have been identified in the coastal region of Guangdong, China. One is Xinzhou thermal water of regional groundwater flow system in a granite batholith and the other is thermal water derived from shallow coastal aquifers in Shenzao geothermal field, characterized by high salinity. The hydrochemical characteristics of the thermal waters were examined and characterized as Na-Cl and Ca-Na-Cl types, which are very similar to that of seawater. The hydrochemical evolution is revealed by analyzing the correlations of components versus Cl and their relative changes for different water samples, reflecting different extents of water-rock interactions and clear mixing trends with seawaters. Nevertheless, isotopic data indicate that thermal waters are all of the meteoric origins. Isotopic data also allowed determination of different recharge elevations and presentation of different mixing proportions of seawater with thermal waters. The reservoir temperatures were estimated by chemical geothermometries and validated by fluid-mineral equilibrium calculations. The most reliable estimates of reservoir temperature lie in the range of 148–162°C for Xinzhou and the range of 135–144°C for Shenzao thermal waters, based on the retrograde and prograde solubilities of anhydrite and chalcedony. Finally, a schematic cross-sectional fault-hydrology conceptual model was proposed.

scholarly journals Geothermal exploitation in the Sani-Afytos area of the Kassandra peninsula (Chalkidiki peninsula, Northern Greece)

2018 ◽  
Vol 40 (3) ◽  
pp. 1162
Author(s):  
Ch. Kougoulis ◽  
A. Arvanitis ◽  
N. Kolios ◽  
S. Koutsinos ◽  
J. S. Kougoulis
Keyword(s):  
Geothermal Gradient ◽  
Geothermal Field ◽  
Thermal Waters ◽  
Tectonic Structures ◽  
Borehole Data ◽  
Northern Greece ◽  
Geothermal Waters ◽  
Geothermal Exploration ◽  
Average Value ◽  
Geothermal Fluids

The Sani-Afytos area in the Kassandra Peninsula (Chalkidiki) was the area of systematic geothermal exploration. Based on deep oil borehole data, the Paleogene, Neogene and Quaternary sediments show significant thickness reaching 3600 m and cover the metamorphosed Mesozoic, mainly carbonate, basement. The detailed water temperature investigation proved the presence of sub-thermal waters (20-28°C) at depths up to 300 m and the spatial distribution of the isothermal curves at depths of 150 and 200 m according to the main NW-SE and SE-NW tectonic structures of the area. Through the construction of geothermal exploration and production wells at depths of 422-583 m, thermal waters of 31.7-36°C were detected within the Upper Miocene sediments. The average value of the geothermal gradient was calculated to be 3-4°CI 100 m. One production well of 520 m depth provides waters of 34°C while its potential flow rate is approximately 50 m /h. The geothermal waters were classified in Na-HCOi and Na-CI types of waters with TD. S 0.89-2.03 g/l. With the aid of chemical geothermometers the deep temperature was estimated to be 80-100°C. In one exploration well, the presence of gas phase (77% v/v CH4, 21.8% v/v N2) was detected. The geothermal exploration resulted in the characterization of the area as the "geothermal field of Sani-Afytos" and in the prospective development using the geothermal fluids in the tourism and other activities.

Sign in / Sign up

Export Citation Format

Share Document