New Isotope–Geochemical Data on the Thermal Waters of the Talskoe Deposit (Magadan Oblast)

In this paper, we summarize new data on the chemical and isotopic composition of thermal wa-ters of the Talskoye deposit in the Magadan Oblast. We were the first to obtain the data on the content of stable oxygen (δ18O) and hydrogen (δD) isotopes in thermal and background waters, as well as oxygen (δ18O) and carbon in bicarbonate ion (δ13C), even though this is the largest ex-ploited deposit of low-mineralized alkaline nitric thermal waters in the region. The thermal water is fresh (M = 980 mg/l), alkaline (pH = 8.9), hydrocarbonate-chloride-sulphate sodium with a high content of fluorine (up to 17 mg/l) and silicic acid (up to 152 mg/l). The deposit is fed by atmospheric precipitation; we did not find traces of melting underground ice supply. A sequential scheme for calculating the temperature of a deep reservoir was applied, which allowed the temperature of water formation to be constrained at 108 °C suggesting an input of fluids rich in potassium and sulfate ion.

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Isotopic-geochemical features of thermal water of the Kyndyg deposit (Republic of Abkhazia)

LITOSFERA ◽

10.24930/1681-9004-2020-20-2-280-298 ◽

2020 ◽

Vol 20 (2) ◽

pp. 280-298

Author(s):

S. S. Potapov ◽

D. V. Kiseleva ◽

O. Ya. Chervyatsova ◽

N. V. Parshina ◽

M. V. Chervyakovskaya ◽

...

Keyword(s):

Thermal Water ◽

Sea Water ◽

Trace Element Composition ◽

Geochemical Data ◽

Thermal Waters ◽

Icp Ms ◽

Different Temperatures ◽

Different Seasons ◽

Karst Waters ◽

Trace Elements In Water

Subject. The aim of the work is to study the mechanism and sources of water formation, as well as the peculiarities of carbonate mineralization in the aquifer of the Kyndyg thermal water deposit. Materials and methods. The samples of water (8) and deposited carbonates (15), collected at different seasons at three sites, characterized by different temperatures and distances from the source, were investigated. pH, Eh, and electrical conductivity were determined by an electrochemical method. For the determination of HCO3 – , Cl– , SO4 2–, titrimetric, mercurymetric and turbidimetric methods were used. Trace element composition was determined by ICP-MS (NexION 300S); strontium isotopic composition – by MC-ICP-MS (Neptune Plus) using the bracketing technique after Sr chromatographic separation. Results. The chloride-calcium hydrochemical type prevails in the studied waters. A number of trace elements in water exceeds the clarke concentrations for groundwater in the supergene zone of mountain landscapes. 87Sr/86Sr isotope ratios (0.7065–0.7072) in thermal waters suggest that their composition is determined rather by the isotopic characteristics of the rocks through which water drains than by the influence of sea water. Among the newly formed carbonates, aragonite prevails. In contrast to thermal water, the concentrations of most metals in carbonates are below the clarke values; only Sr and Se are increased, which content is significantly increased in water as well. Deposited carbonates are characterized by 87Sr/86Sr values (0.7028–0.7074), which are lower than in the source thermal waters. Conclusions. On the basis of hydrogeological, hydrochemical and geochemical data, it can be assumed that the waters of this aquifer complex are formed mainly due to fresh fractured karst waters of lower Cretaceous limestones with submerged monocline dipping into the zone of slow circulation and mixing with sedimentogenic sodium chloride waters. The geochemical data and the presence of scandium anomaly suggest that the underlying Jurassic volcanogenic rocks also participate in water exchange.

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Insights into the Porretta Terme (northern Apennines, Italy) hydrothermal system revealed by geochemical data on presently discharging thermal waters and paleofluids

Environmental Geochemistry and Health ◽

10.1007/s10653-020-00762-5 ◽

2020 ◽

Author(s):

Franco Tassi ◽

Paolo S. Garofalo ◽

Filippo Turchetti ◽

Davide De Santis ◽

Francesco Capecchiacci ◽

...

Keyword(s):

Equilibrium Temperature ◽

Aqueous Fluid ◽

Primary Sources ◽

Geochemical Data ◽

Thermal Waters ◽

Two Phase ◽

Quartz Crystals ◽

Deep Aquifers ◽

Phase Liquid ◽

Deep Fluid

Abstract This study focuses on the geochemical features of the presently discharging thermal and cold springs and on paleofluids from the upstream portion of the Reno river basin (Alto Reno; central–northern Italy). The aim is investigating the primary sources of the modern and fossil fluids and the interactions between deep and shallow aquifers. Paleofluids are from fluid inclusions hosted within euhedral and hopper quartz crystals and consist of a two-phase, liquid–vapor aqueous fluid and a unary CH4 fluid. The aqueous inclusions have constant phase ratios and a calculated salinity of ~ 1.5 wt% NaCleq. They homogenize by bubble disappearance at 100–200 °C, whereas the estimated entrapment depth is ~ 3–5.5 km. The paleofluids likely represent the vestiges of the deep and hot, CH4-rich, Na+–Cl− fluids produced by the interaction between meteoric waters and Triassic and Miocene formations. The modern Na+–Cl−(HCO3−) thermal waters originate from meteoric waters infiltrating SW of the study area, at elevation > 800 m a.s.l., circulating within both the Triassic evaporites and the overlying Miocene turbiditic formations, where salt dissolution/precipitation, sulfate reduction, and production of thermogenic CH4 occur. The equilibrium temperature of the deep fluid source is ~ 170 °C, corresponding to > 5 km depth. Cold springs are Ca2+–HCO3− type and show low amounts of biogenic CO2 and CH4 with no inputs of deep-originated fluids excepting in the immediate surroundings of the thermal area, confirming the lack of significant hydraulic connection between shallow and deep aquifers. We propose a genetic link between the quartz-hosted paleofluid and the thermal waters present in the area.

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NEW ISOTOPE-GEOCHEMICAL DATA ON TAVATUM THERMAL WATERS (MAGADANSKAYA OBLAST)

Tikhookeanskaya Geologiya ◽

10.30911/0207-4028-2021-40-5-104-114 ◽

2021 ◽

Vol 40 (5) ◽

pp. 104-114

Author(s):

G.A. Chelnokov ◽

◽

I.V. Bragin ◽

N.A. Kharitonova ◽

◽

...

Keyword(s):

Chemical Composition ◽

Surface Waters ◽

Chemical Elements ◽

Geochemical Data ◽

Thermal Waters ◽

Time Data ◽

Chemical Research ◽

High Temperature Processes ◽

Cationic Exchange ◽

The Impact

The article presents the results of isotope-chemical research of the Tavatum thermal water deposit (coast of the Sea of Okhotsk, Magadanskaya Oblast), as well as surrounding underground and surface waters. For the first time, data on the content of isotopes of oxygen and hydrogen in the underground and surface waters were obtained, and the analysis of trace elements was performed. The results show that the chloride sodium-calcium mesohalinous thermal waters of the Tavatum deposit are atmogenic; two processes can be considered as the main processes of the chemical composition formation: 1) involvement of deep brines (including cryopeg waters) and 2) cationic exchange in the interaction of sea waters (buried during marine transgressions in the Holocene) with rocks. In the chemical composition of thermal waters, there are indicator chemical elements reflecting the impact of deep high-temperature processes. The temperature of the deep fluid estimated by different geothermometers is 117 to 128°C, and the depth of formation is at least three kilometers.

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