Chemical composition of bottled mineral waters in Estonia

Five commercially available in Estonia brands of bottled water have been analysed for 59 chemical elements by ICP-QMS and ICP-AES techniques to assess the quality of domestic mineral waters in scope of the European Groundwater Geochemistry Project initiated by the Geochemistry Expert Group of EuroGeoSurveys. Contents of 9 cations and anions, pH and electrical conductivity (EC) were measured in the bottled mineral waters by IC, titration and photometric methods. The data showed a significant difference between natural undiluted mineral water (Värska Originaal) characterised by the highest values of pH, EC and majority of trace elements studied, and other domestic waters sold in Estonia.     

Trace elements and ions in Italian bottled mineral waters: Identification of anomalous values and human health related effects

Microbiological studies have always had an important role in the evaluation of drinking water quality. However, since geological processes are the most important factors controlling the source and distribution of chemical elements in natural waters, the importance of geochemical data must not be underestimated. This study presents data on pH, conductivity and concentrations of 69 elements and ions (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, I, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Te, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn, Zr, Br⁻, HCO₃⁻, Cl⁻, F⁻, NH₄⁺, NO₂⁻, NO₃⁻, PO₄³⁻, SO₄²⁻, SiO₂) from 186 bottled mineral waters of 158 different Italian name brands. Analyses show a large range in concentrations for most of these elements, with variations up to four orders of magnitude. Our data demonstrate that some elements (such as Be), generally considered unlikely to occur, can instead reach surprisingly high levels in drinking water, and also how packaging can release some trace elements to the bottled water. Data analysis shows that the implementation of an international database of bottled water geochemistry and of potential toxicological effects is of paramount importance to provide a robust data set which would be useful to set international action levels and guidelines to secure bottled water quality, whose consumption has steadily increased in the recent years. A new formula to calculate nitrate and nitrite tolerable concentration levels in waters intended for human consumption is proposed, to take into account that about 5% of dietary nitrate in humans is converted to nitrite.     

Composition and variation of major and trace elements in Croatian bottled waters

Within the framework of the Pan-European project about the geochemistry of bottled mineral waters in Europe launched in 2007 by the European Geological Surveys (EGS) Geochemistry Expert Group fourteen brands of bottled natural waters from Croatia of both mineral and spring types were evaluated for getting more coherent spatial information about the natural variation of element concentration in bottled waters found at the European market. Results of chemical analysis show that not a single one out of fourteen analyzed bottled waters from Croatia exceeds the Croatian water standards sanctioning thereby their suitability for human consumption. Also, statistical tests performed for 41 analytes (including pH and EC) clearly show that the water chemistry is in a high degree of conformity with regional geology, depending on structural, stratigraphic and, above all, lithological diversity of aquifers. Thus Dinaric and Pannonian parts of Croatia differ largely with regard to their water types: Dinaric region is completely lacking mineral water types while, on the other side, in the Pannonian region even the spring waters show stronger mineralization in comparison with their Dinaric counterparts. Typically, all natural waters from Croatia bear the bicarbonate (HCO₃) signature. However, Ca–Mg cation pair combination is characteristic of spring waters while Na–K dominates in the mineral waters.     

The chemistry of the anoxic waters in the Framvaren Fjord,Norway

In the summer of 1993, a number of chemical parameters (H₂S, O₂, pH, TA, TCO₂, NH ₄ ⁺ , PO ₄ ^3– , SiO₂, Mn²⁺ and Fe²⁺) were measured in the Framvaren Fjord, a permanently super-anoxic fjord in southern Norway. The extremely steep gradient of sulfide near the interface suggests that other than downward flux of oxygen, three other possible oxidants, particulate manganese and iron oxides, phototrophic sulfur oxidation bacteria and horizontally transported oxygen account for the oxidation of the upward flux of H₂S. Water intrusion through the sill accounts for the temperature inflection above the interface, which, together with internal waves (Stigerbrandt and Molvaer, 1988), may cause fluctuations of the depth of interface. Significant gradients of hydrographic properties and chemical species between 80–100 m suggest that there is a second interface at about 90 m that separates the deep and older bottom waters. A stoichiometric model is applied to examine the biogeochemical cycles of S, C, N and P in the Framvaren. High C:S, C:N and C:P ratios are found while the nutrients (N, P) have Redfield ratio. Based on the C:N:P ratio of 155:16:1 in organic matter, about 30% of sulfide produced by sulfate reduction is estimated to be removed by processes such as oxidation, formation of FeS₂, degassing and incorporation into organic matter. The rates of oxidation of H₂S by Mn and Fe oxides in the water near the interface were slightly faster than the observed values in the laboratory, probably due to the presence of bacteria.     

Classification of natural mineral and spring bottled waters of Portugal using Principal Component Analysis

Considering its area, Portugal is one of the world's richest countries in mineral and spring waters. There are 33 different types of bottled water, 18 of which are classified as natural mineral water and the remaining as spring water. The majority of these waters are of low mineralisation in comparison to most European bottled waters.     

Petrogenesis of ultramafic and mafic xenoliths from Mesozoic basanites in southern Sweden: constraints from mineral chemistry

Jurassic basanite necks occurring at the junction of two major fault zones in Scania contain ultramafic (peridotites, pyroxenites) and mafic xenoliths, which together indicate a diversity of upper mantle and lower crustal assemblages beneath this region. The peridotites can be subdivided into lherzolites, dunites and harzburgites. Most lherzolites are porphyroclastic, containing orthopyroxene and olivine porphyroclasts. They consist of Mg-rich silicates (Mg# = Mg/(Mg + Fe_tot) × 100; 88–94) and vermicular spinel. Calculated equilibration temperatures are lower in porphyroclastic lherzolites (975–1,007°C) than in equigranular lherzolite (1,079°C), indicating an origin from different parts of the upper mantle. According to the spinel composition the lherzolites represent residues of 8–13% fractional melting. They are similar in texture, mineralogy and major element composition to mantle xenoliths from Cenozoic Central European volcanic fields. Dunitic and harzburgitic peridotites are equigranular and only slightly deformed. Silicate minerals have lower to similar Mg# (83–92) as lherzolites and lack primary spinel. Resorbed patches in dunite and harzburgite xenoliths might be the remnants of metasomatic processes that changed the upper mantle composition. Pyroxenites are coarse, undeformed and have silicate minerals with partly lower Mg# than peridotites (70–91). Pyroxenitic oxides are pleonaste spinels. According to two-pyroxene thermometry pyroxenites show a large range of equilibration temperatures (919–1,280°C). In contrast, mafic xenoliths, which are mostly layered gabbronorites with pyroxene- and plagioclase-rich layers, have a narrow range of equilibration temperatures (828–890°C). These temperature ranges, together with geochemical evidence, indicate that pyroxenites and gabbroic xenoliths represent mafic intrusions within the Fennoscandian crust.     

Strong, localised country-rock contamination and partial homogenisation of a mafic magma: An example from west central Sweden

A dolerite sill cutting slightly older basalt in west-central Sweden shows a strong chemical variation (54% < SiO₂ < 73%) within a restricted area (< 100 × 100 m²). The linear correlation among almost all elements is extremely high; in addition, _NdT is strongly correlated with the SiO₂ content. Least-square hyperbolic-ratio and three-element ratio modelling (common denominator) suggests that most of the chemical variation is explained by mixing and/or micro-mingling. In all, we test 407 hyperbolas, of which 402 are fitted. The five ratio pairs, which could not be fitted to a hyperbola using a least-square fitting procedure, have the ratio Th / Eu in common. Testing the goodness of fit is problematic for hyperbolic distributions; for comparing purposes we sum the distances to chords approximating the hyperbola. Mobile and immobile elements behave similarly, suggesting that no elements are lost or added from outside the system. The data suggests that already the most mafic of the analysed rocks is a mixture of the ‘normal’ dolerite and a siliceous crustal rock. A mafic magma intruded into the base of the crust, where it fractionated resulting in a decreased Mg number. The magma was then contaminated with country rocks in an intermediate magma chamber due to country rock melting; during mixing/mingling almost no fractionation took place. The contaminated rock suggests the presence of a fluid phase. This was probably a prerequisite for country-rock melting. Enrichment in some incompatible elements suggests that besides major mixing/mingling a thermochemical separation process has affected the most felsic rock enriching it in light rare earths and Zr.     

Pyroxenite xenoliths and clinopyroxene megacrysts from the Cenozoic Jbel Saghro Volcanic Field (Anti-Atlas,Morocco): Petrography,mineral chemistry and equilibration conditions

A suite of mafic pyroxenite xenoliths and clinopyroxene megacrysts was brought to the surface by Cenozoic nephelinites of the Jbel Saghro Volcanic Field (Anti-Atlas, Morocco). The large population of samples was subdivided into five groups: (i) clinopyroxenites sensu stricto; (ii) olivine clinopyroxenites; (iii) mica-bearing clinopyroxenites; (iv) kaersutite-bearing clinopyroxenites; (v) clinopyroxene megacrysts. These xenoliths display a cumulate texture (adcumulate, heteradcumulate with poikilitic clinopyroxene including olivine). The clinopyroxenes have the composition of augite and show an appreciable variation of MgO (7.02–14.80 wt.%), TiO₂ (0.58–5.76 wt.%) and Al₂O₃ (2.81–12.38 wt.%) contents in grains. The clinopyroxenes are characterized by convex upward chondrite-normalized REE patterns, they display very similar trace element compositions with low contents of incompatible elements such as Rb (0−0.9 ppm), Ba (0.1–8.3 ppm), Th (0.1−0.3 ppm), U (0.01−0.04 ppm) and Nb (1.3–3.2 ppm). REE contents of the calculated melts in equilibrium with the clinopyroxene megacrysts and clinopyroxene from pyroxenite xenoliths are similar to those of the nephelinites exposed in Jbel Saghro. Crystallization temperatures of pyroxenite xenoliths and clinopyroxene megacrysts range from 950 °C to 1150 °C. Clinopyroxene barometry yielded pressure of crystallization ranging from 0.4 to 0.8 GPa for pyroxenite xenoliths and 0.3 to 0.7 GPa for clinopyroxene megacrysts. This pressure range is in agreement with pyroxenite xenoliths and clinopyroxene megacrysts being crystallized from their parental melts at the lower and upper crust.     

Nature and origin of eclogite xenoliths from kimberlites

Eclogites from the Earth's mantle found in kimberlites provide important information on craton formation and ancient geodynamic processes because such eclogites are mostly Archean in age. They have equilibrated over a range of temperatures and pressures throughout the subcratonic mantle and some are diamond-bearing. Most mantle eclogites are bimineralic (omphacite and garnet) rarely with accessory rutiles. Contrary to their overall mineralogical simplicity, their broadly basaltic-picritic bulk compositions cover a large range and overlap with (but are not identical to) much younger lower grade eclogites from orogenic massifs. The majority of mantle eclogites have trace element geochemical features that require an origin from plagioclase-bearing protoliths and oxygen isotopic characteristics consistent with seawater alteration of oceanic crust. Therefore, most suites of eclogite xenoliths from kimberlites can be satisfactorily explained as samples of subducted oceanic crust. In contrast, eclogite xenoliths from Kuruman, South Africa and Koidu, Sierra Leone stem from protoliths that were picritic cumulates from intermediate pressures (1–2 Ga) and were subsequently transposed to higher pressures within the subcratonic mantle, consistent with craton growth via island arc collisions. None of the eclogite suites can be satisfactorily explained by an origin as high pressure cumulates from primary melts from garnet peridotite.     

Mobilization and redistribution of major and trace elements in two weathering profiles developed on serpentinites in the Lomié ultramafic complex, South-East Cameroon

The behaviour of major and trace elements have been studied along two serpentinite weathering profiles located in the Kongo-Nkamouna and Mang North sites of the Lomié ultramafic complex.The serpentinites are characterized by high SiO₂ and MgO contents, very low trace, rare earth and platinum-group element contents. Lanthanide and PGE contents are higher in the Nkamouna sample than in Mang North. Normalized REE patterns according to the CI chondrites reveal that: (i) all REE are below chondrites abundances in the Mang North sample; (ii) the (La/Yb)_N ratio value is higher in the Nkamouna sample (23.72) than in the Mang one (1.78), this confirms the slightly more weathered nature of the Nkamouna sample. Normalized PGE patterns according to the same CI chondrites reveal a negative Pt anomaly in the Mang sample. The Nkamouna sample is characterized by a flat normalized PGE pattern.All element contents increase highly from the parent rock to the coarse saprolite.In the weathering profiles, Fe₂O₃ contents decrease from the bottom to the top contrarily to Al₂O₃, SiO₂ and TiO₂. The contents of alkali and alkaline oxides are under detection limit.Concerning trace elements, Cr, Ni, Co, Cu, Zn and Sc decrease considerably from the bottom to the top while Zr, Th, U, Be, Sb, Sn, W, Ta, Sr, Rb, Hf, Y, Li, Ga, Nb and Pb increase towards the clayey surface soil. Chromium, Ni and Co contents are high in the weathered materials in particular in the saprolite zone and in the nodules.REE contents are high in the weathered materials, particularly in Nkamouna. Their concentrations decrease along both profiles. Light REE are more abundant than heavy REE. Normalized REE patterns according to the parent rock reveal positive Ce anomalies in all the weathered materials and negative Eu anomalies only at the bottom of the coarse saprolite (Nkamouna site). Positive Ce anomalies are higher in the nodular horizon of both profiles. An additional calculation method of lanthanide anomalies, using NASC data, confirms positive Ce anomalies ([Ce/Ce^*]_NASC = 1.15 to 60.68) in several weathered materials except in nodules ([Ce/Ce^*]_NASC = 0.76) of the upper nodular horizon (Nkamouna profile). The (La/Yb)_N ratios values are lower in the Nkamouna profile than in Mang site.PGE are more abundant in the weathered materials than in the parent rock. The highest contents are obtained in the coarse saprolite and in the nodules. The elements with high contents along both profiles are Pt (63–70 ppb), Ru (49–52 ppb) and Ir (41 ppb). Normalized PGE patterns show positive Pt anomalies and negative Ru anomalies.The mass balance evaluation, using thorium as immobile element, reveals that:

– major elements have been depleted along the weathering profile, except for Fe, Mn and Ti that have been enriched even only in the coarse saprolite;

– all the trace elements have been depleted along both profiles, except for Cr, Co, Zn, Sc, Cu, Ba, Y, Ga, U and Nb that have been enriched in the coarse saprolite;

– rare earth elements have been abundantly accumulated in the coarse saprolite, before their depletion towards the top of the profiles;

– platinum-group elements have been abundantly accumulated in the coarse saprolite but have been depleted towards the clayey surface soil.

Moreover, from a pedogenetical point of view, this study shows that the weathering profiles are autochtonous, except in the upper part of the soils where some allochtonous materials are revealed by the presence of zircon grains.     

The content of some microelements in mineral waters from Covasna and Harghita Romanian districts

Using two analytical techniques, CSV/ASV and ICP–AES, the concentration of some microelements (lead, zinc, manganese) in mineral waters from the Covasna and Harghita districts of Romania were determined. The optimum parameters for the voltammetric determination of manganese, copper, zinc and lead were established (electrolyte, deposition time, pulse duration, pulse amplitude, etc.) and then the content of these elements in twelve samples of mineral water were determined. The results obtained by both techniques led to the conclusion that the concentration of microelements in mineral waters from Covasna and Harghita districts is connected to the mineral content underground.     

贵州竹林沟锗锌矿床碳酸盐矿物学和矿物化学特征及其地质意义

以碳酸盐岩为容矿岩石的后生热液铅锌矿床（Mississippi Valley-type,MVT矿床）是世界上一种重要的铅锌矿床类型,也是锗的重要工业来源之一。热液碳酸盐矿物是MVT矿床中最主要的脉石矿物,其形成贯穿整个MVT矿床成矿过程。因此,碳酸盐矿物携带丰富的成矿信息,是认识MVT矿床成因的重要补充。位于贵州省贵定县境内的竹林沟锗锌矿床,是近年来新发现的富锗锌矿床（平均品位97.9×10^-6 Ge,6.54% Zn）,赋存于泥盆系碳酸盐岩中。本次工作发现该矿床不同期次热液白云石的矿物学和微量元素地球化学特征存在明显差异：成矿期前白云石（Dol1）主要呈细脉状穿插围岩,被成矿期白云石和硫化物脉穿插,部分呈细粒状被后期白云石包裹;成矿早期白云石（Dol2）主要呈粗粒状,与闪锌矿共生;主成矿期白云石（Dol3）主要呈脉状、团块状,与闪锌矿和黄铁矿共生;成矿晚期白云石（Dol4）呈团块状充填于闪锌矿矿石或者围岩中;成矿期后白云石（Dol5）呈脉状穿插或包裹其它期次白云石/闪锌矿-黄铁矿条带。C-O同位素研究表明,成矿期白云石主要来源于碳酸盐围岩的溶解,成矿流体中的C来源于围岩,而较低的δ¹⁸O值可能是亏损¹⁸O的成矿流体和围岩间水/岩反应过程中O同位素发生交换的结果。激光剥蚀电感耦合等离子体质谱（LA-ICPMS）白云石原位微量元素分析结果表明,Dol2-Dol4的Y/Ho比值相对稳定（30.5~47.9）,结合区域成矿特征,认为形成成矿期白云石的流体主要为盆地卤水,与该矿床属于MVT矿床事实吻合。Dol1和Dol5具有相对较低的稀土总量（∑REE=3.97×10^-6~29.7×10^-6）,很可能与白云岩围岩（∑REE=25.2×10^-6~61.3×10^-6）溶解作用有关,直接继承围岩的稀土元素组成特征;成矿期Dol2-Dol4的∑REE较高（∑REE=39.2×10^-6~117×10^-6）,暗示成矿流体本身也携带了部分稀土元素。成矿各期次白云石均具有明显的Eu负异常（δEu=0.38~0.72）特征,指示成矿温度可能较高（>200℃）,Ce正异常相对稳定（δCe=1.10~1.28）,暗示其成矿流体pH值保持弱酸性。综上,本文认为竹林沟锗锌矿床的形成经历如下过程：在伸展背景下,深循环盆地卤水萃取下伏地层和基底岩石中的Zn、Ge和REE等元素,形成富金属流体,受构造作用驱动沿区域性断裂不断向上运移,在赋矿层位与富硫流体发生混合作用,导致闪锌矿等硫化物沉淀;在整个成矿过程,成矿环境经历了还原→氧化的转变,成矿元素发生了共生分异,在竹林沟形成富锗锌矿体,在牛角塘形成富镉锌矿体,而pH始终保持弱酸性,直至被围岩碳酸盐岩中和。

     

6块新回收沙漠陨石的矿物岩石学特征及类型划分

干旱沙漠地区与南极冰盖均有利于陨石样品保存。2013年4-5月,通过首次新疆哈密沙漠陨石考察,回收了陨石样品47块。文中报导其中6块样品的矿物岩石学特征,并划分它们的化学岩石类型。Arlatager004、006、0014、0022和TuzLeik001等5块样品主要由橄榄石、辉石、长石、铁镍金属和陨硫铁组成,具有典型的普通球粒陨石岩石结构特征,其球粒结构不明显,表明经历过较强的热变质,岩石类型划分为5型;根据样品中橄榄石Fa值,低钙辉石Fs值和样品的金属含量等,将Arlatager004、006、0014、0022划分为L5型普通球粒陨石;TuzLeik001划分为H5型普通球粒陨石。Kumtag005具有典型的球粒结构,结合橄榄石Fa值和低钙辉石Fs值以及岩石学特征,将其划分为L3型普通球粒陨石。根据橄榄石Fa值与其百分标准平均方差(PMD)之间的关系,将Kumtag005的岩石类型亚型划分为L 3.4。这6块样品代表了3个化学群,结合该地区回收到的其他陨石分析结果,表明新疆哈密沙漠是一个新的陨石富集区,这些沙漠陨石的发现和研究,必将极大促进中国陨石学和天体化学的发展。     

Hydrogeochemistry and strontium isotopes of spring and mineral waters from Monte Vulture volcano,Italy

This paper describes the results of a study that was conducted to determine the relationship between hydrogeochemical composition and ⁸⁷Sr/⁸⁶Sr isotope ratios of the Mt. Vulture spring waters. Forty samples of spring waters were collected from local outcrops of Quaternary volcanites. Physico-chemical parameters were measured in the field and analyses completed for major and minor elements and ⁸⁷Sr/⁸⁶Sr isotopic ratios. A range of water types was distinguished varying from alkaline-earth bicarbonate waters, reflecting less intense water–rock interaction processes to alkali bicarbonate waters, probably representing interaction with volcanic rocks of Mt. Vulture and marine evaporites. The average ⁸⁷Sr/⁸⁶Sr isotope ratios suggest at least 3 different sources. However, some samples have average Sr isotope ratios (0.70704–0.70778) well above those of the volcanites. These ratios imply interaction with other rocks having higher ⁸⁷Sr/⁸⁶Sr ratios, probably Triassic evaporites, which is substantiated by their higher content of Na, SO₄ and Cl. The Sr isotope ratios for some samples (e.g. Toka and Traficante) are intermediate between the value for the Vulture volcanites and that for the local Mesozoic rocks. The salt content of these samples also lies between the value for waters interacting solely with the volcanites and the value measured in the more saline samples. These waters are thus assumed to result from the mixing of waters circulating in volcanic rocks with waters presumably interacting with the sedimentary bedrock (marine evaporites).     

Determination of major and trace elements in European bottled mineral water — Analytical methods

A total of 1785 European bottled water samples were analyzed using standard laboratory methods. The bottled water samples were purchased in 2008 at supermarkets throughout 40 European countries. The samples were analyzed for 71 chemical parameters (As, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, I, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Te, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn, Zr, Br⁻, HCO₃⁻, Cl⁻, F⁻, NH₄⁺, NO₂⁻, NO₃⁻, PO₄³⁻, SO₄²⁻, SiO₂, pH, and EC) by quadrupole inductively coupled emission spectroscopy (ICP-QMS, trace elements), inductively coupled plasma atomic emission spectroscopy (ICP-AES, major elements), ion chromatography (IC, anions), atomic fluorescence spectrometry (AFS, Hg), titration (alkalinity), photometric methods (NH₄⁺), potentiometric methods (pH), and conductometric methods (specific electrical conductivity, EC). A very strict quality control procedure was followed by analysing blanks, international reference materials, an internal project standard, and duplicate analyses, as well as by analysing 23 elements by both ICP-QMS and ICP-AES. Analysis of marketed bottled water from springs, wells or boreholes, apart from the evaluation of its quality with respect to inorganic elements, it may provide a cheap alternative to obtain a first impression about groundwater chemistry at the European scale.     

Groundwater level and chemistry changes resulting from tunnel construction near Matsumoto City, Japan

 Before tunnel construction began, the groundwater chemical compositions and levels around the tunnel were studied to determine if water compositions could predict whether surface water will be influenced by tunnel construction. When the chemical composition of the well and springwater was similar to that of the tunnel seepage water, and the altitude of the well and spring was above the tunnel level, the groundwater level in the well and spring was influenced by draining tunnel seepage water. Therefore, comparing the chemical compositions of surface water and groundwater may be used for predictive purposes. However, the results of this study showed there was no noticeable chemical composition change in springwater prior to changes in groundwater level at a particular site. The changes in the hydrology of the plateau caused by tunnel construction were also studied, using measurements of the changes in groundwater chemistry as well as changes in groundwater levels. Prior to tunnel construction, river discharge was greater. Following tunnel construction, some river discharge decreased because springwater was drained as tunnel seepage water and the spring in the catchment dried up. Tritium concentration indicated that 3 years after tunnel construction, surface water did not reach tunnel levels in spite of groundwater level lowering and remaining unconfined groundwater being drained. Received: 17 January 1996 · Accepted: 10 July 1996     

Mobility of arsenic and trace element inventories in sediment cores from Masuda City,southwestern Japan

The vertical distribution of arsenic and other trace and major elements has been studied in four sediment cores from Masuda City, Nagashima and Okite in the Shimane Prefecture of southwestern Japan. The sediment cores were also subjected to leaching techniques and ¹⁴C dating. The stratigraphic sequences in the cores consist of silt and sandy silt at top, passing downward into gray to black clays. Elevated values of As, Pb, Zn, Cu, Ni, Cr, and V are present in several horizons while abundances of these elements tend to be higher in the black and gray clays, probably due to adsorption onto clay sediments. Higher concentrations of Fe and total sulfur (TS) occur in black clays. The correlations of the trace metals with iron suggest their adsorption onto Fe (oxy)hydroxides, whereas correlations with sulfur in some cores indicate that they were precipitated as Fe-sulfides. Age determinations suggest that clay horizons at ∼5 m depth were deposited at around 5,000 and 6,000 years BP (¹⁴C ages) during the transgressive phase of sea level change. The results of the leaching techniques in the core samples show that higher amounts of As were extracted with deionized water. Even at neutral pH, As can be released from sediments to groundwater, and therefore groundwater pollution is a concern in Masuda City and the surrounding area.     

Geochemistry of the mineral waters and gases of the Mukhen deposit,Far East

This work reports new hydrochemical data on the two types of cold high p CO₂ groundwaters from the Mukhen deposit (Khabarovsk district). The first type is classed with HCO₃-Ca-Mg waters with a relatively low TDS (up to 1.7 g/l) and high concentrations of Fe²⁺, Mn²⁺, Ba²⁺, and SiO₂. The second type is of HCO₃-Na composition with high TDS (up to 14 g/l) and elevated Li⁺, B, Sr²⁺, Br^?, and I^?. New oxygen (δ¹⁸O) and hydrogen (δD) isotopic data on the waters and carbon (δ¹³C) isotopic data on the gas phase, together with a detailed geological and hydrogeological analysis of the study area, allowed us to decipher the origin of both the mineral waters. Based on the tritium content (³H) in the ground and surface waters of the area, the duration of the mineral water circulation was estimated. It was established that the both types of groundwaters were formed during interaction of meteoric water with bedrock under active influence of CO₂, however HCO₃-Na groundwaters have longer residence time than HCO₃-Ca-Mg groundwaters.     

Unfilterable "geoaerosols", their use in the search for thermal, mineral and mineralized waters, and their possible influence on the origin of certain types of mineral waters

 Many articles describing the unusual mobility of solid particles in the subsurface layers of the Earth's crust have been published in the last decades, especially in the geological literature. In an attempt to explain this phenomenon, several hypotheses have been developed. The one closest to the behavior observed in nature is based on quantum mechanics. Based on this phenomenon, a new geological prospecting method called Molecular Form of Elements (MFE) was developed in former Czechoslovakia during the 1970s. It has been widely applied since for various types of prospecting, including the search for thermal and mineral waters. When using the MFE method for prospecting, the relationship between the ascending mineral springs and the four directions of structural faults was discovered. The possibility of whether a process, similar to the one acting during the absorption of elements when using the MFE method, can be a source of dissolved solid particles during the creation of mineral waters is also discussed. Received: 3 March 2000 · Accepted: 11 July 2000