Hydrothermal Water Research Articles

Biogeography of living fossils as a key for geological reconstruction of the East Mediterranean: Ayyalon - Nesher Ramla system, Israel

The Ayyalon - Nesher Ramla (ANR) system combines hypogenic karst with endemic subterranean fauna. The unique faunal assemblage utilizes chemosynthetic food web based upon H2S within the ascending plumes of hydrothermal water. We attempt to constrain the regional biogeography and the age of the hypogene system using subterranean extant ‘living fossils’, combined with related taxa in the Dead Sea Rift and Mediterranean, as well as geological evidence and previously published molecular phylogenetic data. The molecular evidence of Typhlocaris ayyaloni and T. salentina suggested that ANR aquatic system age is > 5.8 Ma. Evidence from Dead Sea Rift and East Mediterranean biogeographic evolution of aquatic fauna indicates isolation of the rift water bodies from the Mediterranean ~7 Ma. The high endemism of terrestrial troglobites at Ayyalon - Nesher Ramla caves indicate longer isolation age, most probably ~14 Ma – the end of the last transgression which inundated the lower Shefela region. We show that the Ayyalon terrestrial fauna of tropical origin invaded the subsurface warm, humid, and food-rich habitat, escaping middle Miocene surface aridization. Shefela sinkholes preserving middle Miocene sediments share similar features with Nesher Ramla sinkholes, suggesting that they share the same formation processes ~14 Ma, and implying a minimum age of the sulfidic hypogenic aquifer.

Mineralogy of an Appinitic Hornblende Gabbro and Its Significance for the Evolution of Rising Calc-Alkaline Magmas

The magmatic and sub-solidus evolution of calcic amphiboles and Fe–Ti oxides was investigated in the Neoproterozoic Frog Lake pluton, Nova Scotia, Canada, in order to understand the relationship between the history of hydrous magma and the resulting mineralogy. The pluton occurs as sheet-like bodies of hornblende gabbro and hornblendite, with lesser tonalite dykes and granite bodies, interlayed with screens of medium-grade metamorphic country rock. Small, diffuse clots of felsic minerals are present in the gabbro. The subsolidus growth of actinolite occurs in early clinopyroxenes and amphiboles. Ilmenite is the dominant Fe–Ti oxide, as interstitial magmatic crystals. The increase of Mn towards the margin of the ilmenite crystals indicates a gradual increase in oxygen fugacity with time, leading to the precipitation of titanite and ferrohypersthene. The replacement of titanite by ilmenite and ilmenite lamellae in the amphiboles suggests subsequent reducing conditions during the sub-solidus crystallisation. The gabbros in the coeval, but apparently shallower, Jeffers Brook granodiorite laccolith have dominant magnetite and Mg-rich subsolidus amphiboles, which are indicative of high oxygen fugacity. The differences between the two plutons suggest that there was a greater flux of hydrothermal water through the sheet-like architecture of the Frog Lake pluton.

Water-free oil reservoirs: origin and morphology

The features of the morphology and composition of secondary minerals in the reservoir zones of the White Tiger (Bach Ho) deposit (shelf of South Vietnam) and deposits in clay rocks of the Bazhenov formation of the Salym area of Western Siberia are considered. It is shown that the common for these fields is the formation of a reservoir as a result of the leaching effect of high-temperature fluids. The genesis of the reservoir is determined by a complex of secondary minerals, obviously of hydrothermal origin, partially filling caverns and cracks in the rock: native silver – zincous copper – barite – anhydrite – kaolinite – laumontite (White Tiger oilfield) and sulphates of iron, aluminum, sodium and calcium – iron-aluminum alum, alunite, jarosite, mirabilite, melanterite, gypsum (deposit in the rocks of the Bazhenov formation of the Salym area). Diagnostics of secondary minerals was established based on the results of microprobe studies of undisturbed samples and analysis of the composition of water extracts from crushed core samples.The species composition of secondary minerals indicates a high temperature of the affected solutions, which varied from 600 to 200°C in the case of the White Tiger oilfield, and in the range of 350–450°C, in the case of rocks of the Bazhenov formation. Hydrothermal alteration of crystalline rocks with the formation of secondary clay minerals (kaolinite, montmorillonite, hydromica), zeolites and minerals-sulfates, which are crystalline hydrates, occurs with the absorption of huge amounts of water by the rock (up to 4∙108 tons of water per 1 km3 of altered rock). This may be related to the waterlessness (lack of bottom water) of oilfields, the reservoir of which has a hydrothermal origin. It is possible that oil deposits in crystalline rocks with high oil-saturated zones have associated waters of hydrothermal rather than sedimentogenic origin, but they occur at considerable depths and are not penetrated by drilling. This possibility is evidenced by the discovery of hydrothermal water in the basement of the White Tiger reservoir at a depth of 4493 m, which, in terms of chemical composition and mineralization, is close to the waters of sodium chloride hydrotherms of Kamchatka.

Mineralogical and geochemical properties and genesis of kaolin and alunite deposits SE of Aksaray (Central Turkey)

The kaolin and alunite deposits, situated approximately 20 km southeast of Aksaray in Central Anatolia, were formed by hydrothermal alteration related to extensional tectonics from the Upper Miocene to Quaternary, mostly from rhyolitic volcanoclastic rocks. The mineralogical and geochemical properties of the deposits were investigated to explain the stages of hydrothermal alteration and the origin of the deposits. X-ray diffraction (XRD), scanning electron microscopy (SEM), and chemical and stable isotope (O, H, and S) studies were carried out on the alteration minerals (e.g., kaolinite, gypsum, alunite, native sulfur and smectite) of the deposits.Kaolinite/halloysite minerals were determined along with mostly alunite- and silica-group minerals (α-quartz, opal-CT, and tridymite), feldspar, native (elemental) sulfur, and partial hematite, goethite, gypsum, cinnabar and realgar. The δ34S isotope values for alunite, gypsum and native sulfur are in a fairly narrow range and vary from 5.03 to 6.62‰, 4.5–5.24‰ and 5.97–7.49‰, respectively. The δ18O values of the kaolinites and smectites vary from +1.8 to +13.3‰ and from −98 to −152‰, respectively, and their δD values range from −4.2 to 15.7‰ and from −93 to −191‰, respectively, showing a spread that is very close the primitive magmatic water line. From the δ18O values, the calculated formation temperatures of the kaolinites and smectites range from 38 to 135 °C and from 29 to 189 °C, respectively. The δ18O values of the alunites and amorphous silica vary from 4.4 to 8.9‰ and from −1.1 to 8.4‰, respectively, and the δD values vary from −72 to −87‰, and from −104 to −191‰, respectively. In addition, the formation temperatures of alunite and amorphous silica minerals range from 57 to 100 °C and from 139 to 281 °C, respectively. Hydrothermal alteration progressed in different stages between 29 and 281 °C according to the calculated modal formation temperatures. The isotopic mineral data suggest that the original hydrothermal waters were a mixture of magmatic and meteoric waters. Oxygen and deuterium analyses indicate that kaolinite and alunite formed at lower temperatures than smectite and silica minerals. The determined stable isotopic compositions of the minerals indicate that hydrothermal solutions at different compositions and temperatures played important roles in the formation of minerals. The determined neoformed minerals may have been formed by steam-heated hydrothermal solutions sourced from rhyolitic magma and are mostly of hypogene origin.

Monitoring temporal variations in the geothermal activity of Miocene Lesvos volcanic field using remote sensing techniques and MODIS – LST imagery

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.

Formation and genesis of Paleozoic sediment-hosted barite deposits in Turkey

Most barite deposits in Turkey are sediment-hosted deposits which are located in different lithologies within passive margin sediments from the Paleozoic. The Şarkikaraağaç, Hüyük and Tordere deposits occur in the western part of the Tauride-Anatolide tectonic unit, whereas the Şekeroba and Önsen region deposits located in the eastern part of Turkey occur on both Arabian and Tauride-Anatolide microplates. While the former deposits occur as both concordant and discordant bodies within Early Paleozoic carbonates, the latter deposits are found as discordant, fracture filling and replacement-type ore bodies.O, D, S, Sr and Pb isotope studies were used to determine and correlate the formation conditions of these deposits. δ18OSMOW mean values of the Tordere barite deposit are slightly higher (mean 16.2‰) than the mean values for the Şekeroba (10.8‰) and Önsen (11.3‰) deposits. The δ18OSMOW (mean 15.83‰) and δDSMOW (mean −67‰) values obtained from fluid inclusions in quartz veins in the Şekeroba barite deposit correspond to metamorphic or deep circulation hydrothermal waters. Mean δ34 SCDT values from Şekeroba, Tordere and Önsen deposits are 31.7, 33.8 and 20.6‰, respectively, which are compatible with the early Paleozoic seawater, except for the Önsen deposit.87Sr/86Sr mean values for the barite deposits of Turkey are defined as follows (‰); Şekeroba: 0.713, Önsen: 0.711, and Tordere: 0.711, which are higher 87Sr/86Sr isotope ratios than Paleozoic seawater. The Pb isotope values in Şekeroba and Tordere deposits are similar and mean is 206Pb/204Pb = 18.28, 207Pb/204Pb = 15.67 and 208Pb/204Pb = 38.50. High radiogenic Sr and Pb isotope data from the deposits indicate that Ba was generated from thick Paleozoic clastics or the older crust beneath them.Sr, S, and O isotopes and the positive Gd anomaly in the barites are very similar to those of Paleozoic stratiform cold-seep barites. The primary stratiform-stratabound barite deposits, like Şarkikaraağaç-Hüyük deposit, could have formed either by cold seep or diagenetic processes at the sediment–seawater interface or within the sediment related to sulfate-methane boundary. Although there are similar Sr and Pb isotopic signatures between the western and eastern region deposits, the eastern region Şekeroba, Önsen and Tordere barite deposits show discordant ore geometry and highly radiogenic isotope values indicating that primary stratabound-stratiform barite was dissolved and remobilized along deep-seated fault zones during the Hercynian orogenesis and deposited in different Paleozoic lithologies related to cooling and/or increase in Eh.

Investigation of the Effect of Hydrothermal Waters on Radionuclide Activity Concentrations in Natural Marble with Multivariate Statistical Analysis

The study aims to investigate the effects of Burdur (Turkey) marble on human health by interpreting their radioactivity concentration (226Ra, 232Th, and 40K), radiological hazard parameters, chemical concentration, physical properties, and all data related to these features by using multivariate statistical methods. Chemical and radionuclide analyses were performed on marble samples. The data were interpreted by statistical analysis. According to the regression model, an increase in the concentration of vanadium carried to the environment by hydrothermal waters causes a 4.452-fold higher concentration of 226Ra. The R2 value of the model was 0.64 and it was statistically significant. The maximum concentration of 226Ra in Isparta Davraz Beige sample (M7) exceeded the values of some countries’ standards. Except for M7, the analyzed sorts of marble can be used safely in dwellings and public buildings.

Clay mineral transformations in anthropic organic matter-rich sediments under saline water environment. Effect on the detrital mineral assemblages in the Upper Chicamocha River Basin, Colombia

The results of this study showed how clay mineral assemblages from alluvial sediments were used to deduce the environmental impact of anthropogenic modifications in the Upper Chicamocha River Basin (UCRB) in Colombia. Two dams were investigated: La Playa dam (with anthropogenic input from farm activities and wastewater) and Sochagota Lake dam (with input from natural hydrothermal waters) and found to contain organic-rich deposits modified under highly saline, eutrophic conditions. Results from X-ray diffraction (XRD), scanning electron microscope (SEM) and analytical high resolution electron microscope AEM-HRTEM analyses indicated that the mineral assemblage in the sediments trapped in La Playa dam in the upper part of the basin is characterized by the presence of Fe-bearing smectite (up to 0.4 atoms per formula unit (a.p.f.u.)), whereas sediments downstream the Sochagota Lake dam are characterized by the presence of illite and dispersed fragments of pyrite framboids. Intense eutrophication due to organic compounds and nutrient loads from urban wastewater and agricultural activities in the area above La Playa dam created a reducing environment in which sediments promoted Fe-uptake in authigenic smectite and efficiently trapped it in the sediments. Periodic release of water from Sochagota Lake into the Chicamocha River allowed the incorporation of detrital illite grains and fragments of pyrite framboids (formed by low temperature illitization and Fe-uptake in the lake sediments) into the alluvial sediments in the lower section of the UCRB.

Hydrothermal leaching of ternary and binary lithium-ion battery cathode materials with citric acid and the kinetic study

Metal ions in ternary LIB cathode materials (LiCoO2/LiNiO2/LiMn2O4) were leached into hydrothermal water with citric acid at 60–90 °C. The leaching efficiency increased with temperature and time. Mn ion was completely leached at 60 °C for 5 min, and at 90 °C for 20 min, the leaching efficiencies of Li, Ni, and Co arrived at 81 %, 73 %, and 100 %, respectively. Hydrothermal leaching has a higher rate than the traditional method and avoids the pollutions caused by high-concentration acids and reductants like H2O2. To improve the Ni leaching efficiency, hydrothermal leaching of binary LIB cathode materials (LiCoO2/LiNiO2) with citric acid was performed at 90–120 °C. At above 100 °C for 20 min, the Ni leaching efficiency reached to 90 %. A shrinking unreacted-core model was adopted to predict reaction behavior, and the activated energy for leaching each metal was calculated. Additionally, a reasonable correlation of the rate constants of Co leaching at different pulp densities was attempted.

Temporal variation of titanite morphology and chemistry in a long-lived shear zone: The Clarke Head syenite in the Minas Fault Zone, Nova Scotia

The mineral chemistry of titanite has been studied in hydrothermally altered syenite preserved as blocks in a salt wall within a regional intracontinental shear zone. The study focusses on the controls on temporal variation in REEs, Zr, Nb, U and Th. Several generations of titanite are recognised on the basis of morphology, chemistry, and relationship to other secondary minerals. Magmatic euhedral to subhedral titanite has Ti and Zr contents characteristic of magmatic titanite in other studies, but does not have a magmatic abundance of REE. Rather, it is 102–104 times depleted in LREE and only slightly depleted in HREE. The leaching of LREE began during a regionally recognised phase of potassic alteration, as amphibole and biotite in gabbro and diorite recrystallized along shear zones and released K, Ca, and F. Later, some 15 Ma after emplacement, the alkali feldspar in the syenite was largely altered to scapolite and analcime by interaction with adjacent halite and gypsum deposits. Titanite formed at that time, from dissolution-reprecipitation reactions in large rutile crystals, is less depleted in LREE, as a result of the dominance of Cl− in hydrothermal waters. Following that event, F−-dominated hydrothermal waters prevailed again, resulting in more LREE depletion in previously formed titanite and in neoformed hydrothermal titanite. At that time, there was also depletion in Zr and U. The trace elements in hydrothermal titanite are thus very informative on the hydrothermal history of the rocks. A combination of morphology and trace-element signature allows different hydrothermal stages to be distinguished.

The source of boron in Quaternary sediments of Dangxiong Co, Tibetan Plateau, China

Dangxiong Co is a salt lake located in the center of the Tibetan Plateau, China. We studied the petrology, mineralogy, geochemistry and microfossil assemblages in the Quaternary, first terrace of Dangxiong Co. Limnocytherellina was the most common ostracode in the first terrace and prefers warm-humid conditions. Grainy ankerite in the terrace exhibits obvious overgrowth edges and uneven surfaces. Rare earth elements and Y distribution patterns in the first terrace show moderate rare earth enrichment, whereas Eu and Dy show weak negative and positive anomalies, respectively. These features indicate that the first terrace in Dangxiong Co is composed of lacustrine hydrothermal deposits. Moreover, the δ11B value of the Quaternary travertine is low, reflecting the low values in hydrothermal waters of the Quaternary. We suggest that hydrothermal water has been an important source of boron in the Quaternary. The three rivers on the south side of Dangxiong Co contribute 95% of the B2O3. The geochemical characteristics and the δ11B values of the waters in these three rivers are the same as in waters from Maerzuo hot spring. Thus, the hot spring is still the main source of boron to Dangxiong Co. These results have important implications for future exploration of borate deposits in salt lakes.

Modeling solute transport in karst fissure dual porosity system and application: A case study in an arsenic contamination site.

Fractures and fracture networks are key conduits for migration of hydrothermal fluids, water and contaminants in groundwater systems Modeling is widely used to understand the environmental risk associated with migration of pollutant for different hydrogeological conditions. In this paper, we proposed a conceptual and mathematical model of flow and transport phenomena in fractured rock systems, and applied in a arsenic contaminate site as a case study. The groundwater flow model and arsenic migration model in fissure-matrix dual system were established. The results show that the velocity of groundwater is positively correlated with inlet pressure, but not with the porosity of the fracture. When the velocity of groundwater is relatively high, arsenic is transported along with the current in a finger-like manner. The distribution of arsenic concentration on the fracture surface is heterogeneous and the phenomenon of diffusion from the fracture to the matrix is not obvious. Indeed, when the velocity of groundwater is relatively small, the arsenic moves forward slowly, the concentration distribution on the crack surface is relatively uniform, and the diffusion phenomenon from the crack to the matrix is more significant.

Acoustic noise spectra under hydrothermal conditions.

Acoustic noise spectra were studied for the first time in overheated water using sonohydrothermal reactor operating at 20kHz ultrasound in the temperature range from 25 to 200°C at the autogenic pressure of 1-14bar. The obtained results highlighted a dominating role of stable cavitation during ultrasonic treatment of hot water. Heating of sonicated water results in the formation of large number of nonlinearly oscillating bubbles synchronous with the driving frequency. At 200°C, the acoustic spectra also display strong subharmonic and multiple ultraharmonic bands. Moreover, cavitation bubbles formed at 200°C exhibit chaotic and random motions. It has been shown that the addition of TiO2 nanoparticles to hydrothermal water heated at 200°C allows to eliminate subharmonic/ultraharmonic bands and stochastic oscillations as well. This effect was assigned to Pickering-like bubble stabilization due to the particle accumulation at the bubble surface.

Role of AhR and Foxo1 in skin inflammation in burn animal model via MAPK signaling pathway

Burn generally refers to thermal damage, including tissue damage caused by hydrothermal (water, soup, oil, etc.), flame, steam, high-temperature gas, hot metal liquid or solid (such as molten steel, ingot). However, little is known about the pathogenesis and inducement of skin inflammation in burned rats. Therefore, this study has carried out an in-depth analysis of the related causes of skin inflammation in burned rats. We analyzed the gene expression and the differentially expressed genes co-expression in burned rats. Subsequently, a set of functional dysfunction modules about inflammation of skin tissue in burned rats were obtained by comprehensive enrichment analysis. In addition, based on related network prediction analysis, we identified a number of regulatory factors, such as endogenous genes, nCRNAs, and transcription factors that have potential monitoring effects on skin inflammation in burned rats. Firstly, we obtained 2679 differentially expressed genes and 7 disease-related dysfunction modules in burned rats. Secondly, we identified a series of regulators related to skin inflammation in burned rats, including 117 ncRNAs (including miR-17-5p, miR-122-5p, and miR-140-5p), 31 transcription factors (including AhR, Foxo1 and Sp1) and 10 endogenous genes (including Il5, Atp5d, and Cox4i1). Core transcription factors AhR and Foxo1 may induce skin inflammation in burned rats through the cascade of MAPK signals. According to the results of this study, we can show a new method for biologists and pharmacists to reveal the inducement of skin inflammation in burned rats and provide a valuable reference for different treatment options.

Hydrothermal Fluid Particle Geochemistry of Submarine Vents in Kos Island, Aegean Sea East Mediterranean

The study aims to fill the gap of knowledge in the literature concerning submarine hydrothermal activity on the eastern part of Hellenic Volcanic Arc. Hydrothermal fluids were collected by scuba diving in active shallow hydrothermal venting areas on Kos Island in the Aegean Sea in East Mediterranean. Analysis was carried out in suspended particles for Fe, Mn, Cu, Pb, Cd, Ca, Ba, Sr, Li, Al and Si. During sampling, gas and water flux was measured and gas/water ratios were estimated. The data presented significant time and spatial variability. The gas flux values in Kephalos Bay varied from 2 to 126 L/h and water flux varied from 60 to 122 L/h. In Bros Thermi the gas flux values varied from 4.5 to 60 L/h and the water flux was found to be from 16.5 to 96 L/h. The suspended particulate matter (SPM) flux varied from 0.93 to 8.64 mg/L and between 0.21 and 20.94 mg/L respectively at two sites studied. Metal/Al ratios also varied significantly within a short distance. The pH of hydrothermal waters was from 5.50 to 5.95 in Kephalos Bay and from 6.09 to 6.53 in Bros Thermi suggesting either different mixing of fluids with seawater deeper in the substrate or perhaps that gases CO2 and H2S control pH values. The main scope of this research is to evaluate the fluxes of gas and water and study the main particulate geochemistry of hydrothermal venting fluids. Hydrothermal particles from the submarine vents studied were dominated by Fe, Ca, Si and Al and strongly enriched in Mn, Cu, Pb and Ba. Based on Metal/Al ratios, it is suggested that there are two distinct hydrothermal reservoirs in Kos. The chemistry of the particles emitted from seeps strongly influence both the marine sediment geochemistry and element distribution locally on the sea bottom while subjected to further transportation, hydrothermal particulates could also affect a much greater region.

Hydrothermal and Cold Spring Water and Primary Productivity Effects on Magnesium Isotopes: Lake Myvatn, Iceland

Lake Myvatn, Iceland, is one of the most biologically productive lakes in the northern hemisphere, despite seasonal ice cover. Hydrothermal and groundwater springs make up the dominant source to this lake, and we investigate their Mg isotope ratio to assess the effect of mid-ocean ridge hydrothermal springs, which are the primary modern sink of seawater magnesium. We also examine a time series in the only outflow from this lake, the Laxa River, to assess the effects of seasonal primary productivity on Mg isotopes. In the hydrothermal waters, there is a clear distinction between cold waters (largely unfractionated from primary basalt) and relatively hot waters, which exhibit over 1‰ fractionation, with consequences for the oceanic mass balance if the hydrothermal removal of Mg is not fully quantitative. The outflow Mg isotopes are similar to basalts (δ26Mg = −0.2 to −0.3) during winter but reach a peak of ∼0‰ in August. This fractionation corresponds to calcite precipitation during summer in Lake Myvatn, preferentially taking up light Mg isotopes and driving the residual waters isotopically heavy as observed, meaning that overall the lake is a CO2 sink.

Hydrated Peridotite–Basaltic Melt Interaction Part II: Fast Assimilation of Serpentinized Mantle by Basaltic Magma

The most abundant terrestrial lavas, mid-ocean ridge and ocean island basalt (MORB and OIB), are commonly considered to be derived from a depleted MORB-mantle component and more specific, variably enriched mantle plume sources. However, findings of oceanic lavas and mafic cumulates issued from melts, enriched in chlorine and having a radiogenic Sr ratio, can be attributed to an interaction between the asthenosphere-derived melts and lithospheric peridotite variably hydrated due to penetration of hydrothermal water down to and below Moho level. To constrain mechanisms and rates responsible for the interaction, we report results of experiments of reaction between serpentinite and tholeiitic basaltic melt. Results show that the reaction proceeds via a multi-stage mechanism: (i) transformation of serpentinite into Cr-rich spinel-bearing harzburgite containing pore fluid, (ii) partial melting and dissolution of the harzburgite assemblage with formation of interstitial hydrous melts, and (iii) final assimilation of the Cr-rich spinel-bearing harzburgite/dunite and formation of hybrid basaltic melts with high MgO and elevated Cr and Ni contents. Assimilation of serpentinite by basaltic melt may occur under elevated melt/rock ratios and may lead to chromitite formation. Our experiments provide evidence that MORB and high-Mg-Cr orthopyroxene-rich cumulates depleted in incompatible elements can be produced from common mid-ocean ridge basaltic melts modified by reaction with hydrated lithospheric peridotite. We established that the rate of assimilation of serpentinized peridotite is controlled by silica diffusion in the reacting hydrous basaltic melt.

Possibility of using thermal water from the Nizhne-Paratunskiye springs of Kamchatka to create pharmaceutical and cosmeceutical compositions

The purpose was to determine content of the main active components — macro- and microelements — in thermal water, in the intermediate product (concentrate) and in the dosage form (spray). Determining the saturation of the dosage form with active components was the purpose as well. Materials and methods. Thermal water from the Nizhne-Paratunskiye springs of Kamchatka, concentrate from this water, composition with a concentrate of thermal water in the form of spray were used. Determination of the content of calcium and magnesium ions was carried out by titrimetric method on the basis of forming a complex compound with Trilon B. Validation of the used methods was carried out. Its repeatability was evaluated within one day to determine the precision of the technique. The intra- and inter-assay precision of the validated method was also evaluated. Solutions containing calcium and magnesium ions in concentrations of 80–120 % from the declared amount were prepared to determine linearity of the methods. Results. The content of magnesium and calcium ions in the raw material (3.63 and 284.41 mg/l, respectively), the intermediate product — concentrate (35.38 and 2723.00 mg/l) and the finished form — spray (11 and 778 mg/l) was determined. Conclusion. As a result of studies based on the determination of the content of macro- and microelements in the spray, concentrate, dosage form, it was found that it is possible to achieve an increase in the content of the trace elements in thermal water, thanks to its 10-fold concentration, which will reduce the cost of transportation. Using the concentrate it is possible to achieve the required salt concentration in the finished product. The developed spray has a complex of auxiliary substances that provide the required consistency of the composition, easily releases hydrothermal water, is chemically indifferent, compatible with salts, absorbs liquid well, is easily removed from the application site, leaves no traces.

Geochemistry of Hydrothermal Particles in Shallow Submarine Hydrothermal Vents on Milos Island, Aegean Sea East Mediterranean

Abstract—The study aims to contribute to submarine hydrothermal particle geochemistry knowledge on the central part of the Hellenic Volcanic Arc. Hydrothermal fluids collected by scuba diving from active shallow hydrothermal venting areas on Milos Island in the Aegean Sea in East Mediterranean. Analysis carried out in suspended particles for Fe, Mn, Cu, Pb, Cd, Ca, Ba, Sr, Li, Al and Si. During sampling, gas and water flux was measured and gas/water ratios were estimated. The data presented significant time and spatial variability. The gas flux values in Palaeochori Bay varied from 4.5 to 63 L/h and water flux varied from 25 to 92 L/h. In Voudia Bay varied from 0.8 to 32 L/h and the water flux found from 7 to 118 L/h while in Adamas Bay the gas flux values were from 2 to 13 L/h and the water flux found from 24 to 72 L/h. The suspended particulate matter (SPM) flux varied from 0.07 to 47 mg/L in Palaeochori Bay, between 2 and 19 mg/L and from 0.8 to 4 mg/L respectively in the three sites studied. Metal/Al ratios also vary significantly within a short distance between seeps in the same area. The pH of hydrothermal waters was from 5.21 to 6.63 in Palaeochori Bay, from 5.45 to 6.39 in Voudia Bay and from 5.69 to 6.10 in Adamas Bay suggesting either different mixing of fluids with seawater deeper in the substrate or perhaps that gases CO2 and H2S control pH values. Based on the geochemical properties found a common geothermal reservoir is suggested located below the surface of the island and annual fluxes of elemental particulates have been estimated. The main scope of this research is to evaluate the fluxes of gas and water and the main particulate geochemistry of hydrothermal venting fluids. Hydrothermal particles from the submarine vents studied were dominated by Fe, Ca, Si and Al and strongly enriched in Mn, Cu, Pb, Ca and Ba. The chemistry of particles emitted from seeps can strongly influence the local sediment geochemistry and element distribution on sea bottom locally while subjected to further transportation can also affect a much greater region.

Brittle tectonics and fluids overpressure during the early stage of the Bay of Biscay opening in the Jard-sur-Mer area, (northern Aquitaine Basin, France)

Ba, F, Pb, Ag, Zn mineral deposits are widespread at the northern and eastern boundaries of the Aquitaine Basin. In most cases, they are hosted within high permeability carbonates that rest over the Hercynian basement and below an impermeable layer. Such a position suggests a Mississippi Valley Type (MVT) model for the formation of these deposits. This model is characterized by the lateral flow of sedimentary fluids expelled from the deeper part of the basin and mixed with other sources of water as they reach the basin boundaries. In the Jard-sur-Mer area, which sits in the north of the Basin, these deposits are also found higher in the sedimentary series suggesting that fluids have flown through the impermeable layer. Our field observations demonstrate that a brittle deformation episode, compatible with an upper-Jurassic N-S direction of extension, occurred as the mineralizing fluids were over pressured. The overpressure was the result of a large input of hydrothermal water ascending along inherited faults affecting the Hercynian basement and released at the onset of the tectonics event. When compared with the rest of the basin, these new results at the northern boundary suggests that the Aquitaine Basin recorded several stages of fluid overpressure both at the onset and during the opening of the Bay of Biscay.