Geochemistry of carbonated mineral waters from the Fadeevskoe deposit of the Primorye region

The geochemical study of bed rocks, underground and surface waters, and associated gases in the Fadeevskoe deposit of carbonated waters (Sikhote Alin, Primorye region) revealed that the chemical composition of these waters is formed in the zone of active water exchange in the limited area of the discharge zone, where hydro carbonate calcic waters with mineralization of up to 1 g/1 are formed in largely potassic-sodic rocks. Calculations of the saturation indices show that the mineral waters are characterized by the early stage of Ca saturation, being undersaturated with carbonates and aluminosilicates. The main factors that influence the water mineralization are the excess carbon dioxide in water and the circulation time. The oxygen and carbon isotope ratios indicate the atmospheric genesis of the aqueous component (δ²H = —117; δ¹⁸O = —15.4%o) and the carbon isotope content in the CO₂ implies the mantle nature of the carbon dioxide (δ¹³C = -9.9%o).     

Geothermal spring causes arsenic contamination in river waters of the southern Tibetan Plateau,China

Large numbers of As-enriched geothermal springs are distributed at the southern Tibetan Plateau, and their influence on river water is still not clear. Lhasa River and its tributary, Duilong Qu located at downstream of the largest geothermal spring of the Tibetan Plateau, were selected for sampling during monsoon and non-monsoon seasons. Dissolved trace elements (B, Cr, Ni, Cu, Zn, As, Cs, Ba and U) were measured in river water samples by ICP-MS. The results show that due to contribution of geothermal spring, As levels of Duilong Qu (205.6 μg/L) and Lhasa River (12.7 μg/L) were higher during non-monsoon season than that of WHO guideline for drinking water (10 μg/L). Accordingly, As level of river water was lower during the monsoon season than that of the non-monsoon season due mainly to dilution process. Therefore, although Tibetan rivers are generally considered as free of contamination, geothermal springs cause As contamination of river water at some local regions and may harm the local residents. Further research is needed in other parts of the plateau to determine whether As level of groundwater of the related region is high.     

Oxygen and hydrogen isotopic ratios in groundwaters and river waters from India

A comprehensive set of measurements of oxygen and hydrogen isotopic ratios in groundwaters as well as waters from rivers, lakes, hot springs etc. taken from a variety of locations in India has been carried out for the first time. Isotopically the most depleted samples occur in the high altitude precipitations in the Himalayas e.g. in the lakes of Bhutan and the source water of the Ganga. The shallow groundwater data display a continental effect where the heavy isotope content decreases with distance from the coast (about 4 to 6 per mil decrease in δ¹⁸O per 1000 km). The δ D and δ¹⁸O of these fresh waters are linearly related and an analysis of this relation vis-a-vis the meteoric water line shows the unambiguous effect of enrichment due to evaporation from soils.     

The behaviour of the rare earth elements during mixing of river and sea waters

Rare earth element concentrations have been measured in organic-rich Luce river water and coastal sea water. Concentrations (e.g. ～350?1850 pmol/kg Nd in the Water of Luce and ～45?350 pmol/ kg Nd in Luce Bay) are related to the presence of particles, with 30–60% of the REE associated with >0.4?0.7 μm particles, and to riverine Fe concentrations. REE fractionation occurs in the river water the submicrometre river water is heavy REE enriched whereas the coarser fraction has a more shale-like REE pattern.Laboratory experiments show that the REE in organic-rich river waters are chiefly associated with Feorganic matter colloids which flocculate during estuarine mixing. Preferential removal of heavy REE (～95%) relative to light REE (～60%) occurs, but no Ce anomaly is developed. In contrast, no REE removal occurs during estuarine mixing with organic-poor river water.     

Suspended matter in surface waters: influence of river discharge and of upwelling*

About 4100 samples of suspended matter were collected by filtration of surface ocean waters in three large regions on the western sides of oceans and two on the eastern sides. Comparison of results shows that the non-combustible fraction (chiefly detrital clays and silts with some siliceous and calcareous skeletal debris) generally dominates along the western sides of oceans, where large contributions of solid detrital sediment are made by rivers that drain much of the adjacent continents. The combustible fraction also is important off these rivers, but it is more important (both relative to the non-combustible fraction and in absolute terms) along the eastern sides of oceans, where upwelling is intense.     

Magmatic Control of Gold Mineralization in Western Primorye

Geology of Ore Deposits - The article analyzes the regional gravitational field of northeastern China, Korea, and Western Primorye. The distribution of gold deposits is compared with the...     

First evidence for the Middle Triassic volcanism in South Primorye

A detailed study of a relatively well-exposed fragment of the Barabash Formation in the southern part of the Voznesenka terrane is carried out to specify the geodynamic settings of the Permian volcanogenic and volcanogenic-sedimentary complexes in South Primorye. It is established that the basaltic flows juxtaposed in the studied sequence originated from sharply different sources. The geochemical characteristics indicate that the basalts from the sequence base were presumably derived by melting of oceanic lithospheric mantle or asthenosphere, while the source of the overlying basalts was lithospheric mantle reworked by a subduction process. The basalts are subsequently overlain by tuffaceous–terrigenous and terrigenous rocks and limestones with remains of Capitanian (Middle Permian) fauna. Accessory zircons extracted from the tuffaceous–terrigenous rocks yield an U–Pb concordant age of 233.3 ± 3.3 Ma (Middle Triassic Ladinian Stage) for the youngest zircon population. The obtained data lead us to conclude that the Barabash Formation is a tectonostratigraphic rather than stratigraphic unit and may be a fragment of the Triassic accretionary wedge. The obtained data cast doubt on the accepted assignment of this unit to the Voznesenka terrane. It is more logical to include it in the Laoelin–Grodekov terrane, which represents a fragment of the Late Paleozoic active continental margin. This suggests that the boundary between these blocks should be specified and the timing of the final stage of amalgamation of the Laoelin–Grodekov terrane with the terranes of the Bureya–Khanka orogenic belt should be revised.     

Effect of engineering-industrial activities in the region of the Kursk Magnetic Anomaly on the ecological state of the river waters

The paper presents analysis of the geochemical state of waters in the fluvial network impacted by the mining and smelting complex and identifies modern technological processes and ecological characteristics of the region controlling the environmental response to anthropogenic impacts and the quality of the waters.     

Late Paleozoic and Mesozoic deformations in the southwestern Primorye region

Two types of tectonic deformations indicating different geodynamic settings are defined in the southwestern Primorye region. Near-latitudinal compression forces were responsible for the oldest, Late Paleozoic deformations. The Permian stratified complexes host a near-meridional system of folds and zones of dynamothermal metamorphism, cleavage, and foliation oriented orthogonally relative to the compression. Late Proterozoic (?) mafic-ultramafic rocks are characterized by similar deformations. In the Late Permian, the deformations were accompanied by granitoid magmatism controlled by fold and cleavage structures. The younger, Mesozoic deformations produced by near-meridional compression are represented by NE-trending sinistral strike-slip faults and their structural parageneses: an ENE-trending system of folds and downdip-thrusts both superimposed on Paleozoic protostructures and manifested in Mesozoic and Cenozoic sequences. It is inferred that, at the Paleozoic-Mesozoic boundary, near-latitudinal compression was replaced by near-meridional compression, probably, in response to the corresponding change in direction of the lateral displacement of the interacting Asian continent and (or) Pacific Plate.     

Dissolved rare earth elements in river waters draining karst terrains in Guizhou Province,China

Winter seasonal concentrations of dissolved rare earth elements (REE) of two major river systems (the Wujiang River system and the Yuanjiang River system) in karst-dominated regions in winter were measured by using a method involving solvent extraction and back-extraction and subsequent ICP-MS measurements. The dissolved REE concentrations in the rivers and their tributaries are lower than those in most of the large rivers in the world. High pH and high cation (i.e., Na⁺ + Ca²⁺) concentrations of the rivers are the most important factors controlling the concentrations of dissolved REE in the river water. The dissolved load (<0.22 μm) REE distribution patterns of high-pH river waters are very different from those of low-pH river waters. The shale (PAAS)-normalized REE patterns for the dissolved loads are characterized by light REE-enrichment and heavy REE-enrichment. Water in the upper reaches of the Wujiang River generally shows light REE-enriched patterns, while that in the middle and lower reaches generally shows heavy REE-enriched patterns. The Yuanjiang River is heavy REE enriched with respect to the light REE in the same samples. Water of the Wuyanghe River draining dolomite-dominated terrains has the highest heavy REE-enrichment. Most river water samples show the shale-normalized REE patterns with negative Ce and Eu anomalies, especially water from Wuyanghe River. Y/Ho ratios show that the water/particle interaction might have played an important role in fractionation between HREE and LREE.     

Geochemistry of organic-rich river waters in Amazonia: Insights on weathering processes of intertropical cratonic terrain

In this study, eight organic-rich rivers that flow through the Brazilian craton in the southwestern Amazon rainforest are investigated. This investigation is the first of its type in this area and focuses on the effects of lithology, long-term weathering, thick soils, forest cover and hydrological period on the dissolved load compositions in rivers draining cratonic terrain. The major dissolved ion concentrations, alkalinity (TAlk), SiO₂, trace element concentrations, and Sr isotope contents in the water were determined between April 2009 and January 2010. In addition, the isotopic values of oxygen and hydrogen were determined between 2011 and 2013. Overall, the river water is highly dilute and dominated by the major dissolved elements TAlk, SiO₂ and K⁺ and the major dissolved trace elements Al, Fe, Ba, Mn, P, Zn and Sr, which exhibit large temporal and spatial variability and are closely correlated with the silicatic bedrock and hydrology. Additionally, rainwater and recycled water vapor and the size of the basin contribute to the geochemistry of the waters. The total weathering flux estimated from our results is 2–4 t km⁻².yr⁻¹, which is one of the lowest fluxes in the world. The CO₂ consumption rate is approximately 21–61 10³ mol km⁻² yr⁻¹, which is higher than expected given the stability of the felsic to basic igneous and metamorphic to siliciclastic basement rocks and the thick tropical soil cover. Thus, weathering of the cratonic terrain under intertropical humid conditions is still an important consumer of CO₂.     

Tectonics of the Cenozoic Nizhnii Bikin coaliferous Depression in the northern Primorye region

The Nizhnii Bikin Depression located in the northern Primorye region is filled with Eocene-CLower Oligocene terrigenous continental coaliferous sediments up to 1500 m thick. The depression resulted from synshear extension during dextral movement along the Alchan Fault (Mishan-CFushun in northeastern China) of the Tan Lu system. The change of the sinistral movement along this fault system dominant in the Cretaceous for the dextral one in the Cenozoic was evidently related to the Indo-Eurasian collision.     

Paleomagnetic studies of the Late Mesozoic deformation stage in the southern Primorye region

The analysis of paleomagnetic data available for the southern Primiorye region revealed that the studied objects were magnetized under regional remagnetization presumably during the Late Mesozoic folding and this magnetization can be interpreted as being synfolding. The interpretation is based on the parameter that characterizes the folding completion degree immediately before regional remagnetization. It is shown that the relaxation of Late Mesozoic horizontal stresses was irregular. The obtained estimates of the degree of folding completion are consistent with the available geological data and Talitskii’s model for tectonic deformations.     

Removal of dissolved boron and silicon during estuarine mixing of sea and river waters

The behaviour of dissolved boron and silicon during mixing of sea and river waters has been studied in two surveys of the estuary of the River Alde in Suffolk, England. Removal of approximately 25–30 per cent was found for both elements. This appears to be the first report of estuarine removal of dissolved boron. The extent of removal of silicon in the Alde is somewhat higher than that found in other estuaries.     

Ore potentiality of the Vanchin Graben, Primorye, Russia

New data on Cenozoic mineralization in the Vanchin coal basin are presented. In addition to the Au-Ag quartz-adularia veins known since the 1970s (Soyuzny deposit), stratified Au-Ag mineralization in tuffaceous-sedimentary rocks, porphyry tin mineralization in the extrusion of tourmalinized rhyolite, metalliferous coal seams enriched in Au, Ge, and REE are hosted in this graben. The localization and chemical and mineral compositions of these types of mineralization are considered. It is shown that Au-Ag mineralization is more widespread in the graben that was previously supposed. The anomalous and diverse mineralization of the Vanchin Graben is attributed, first of all, to long-term evolution of volcanism and hydrothermal activity developing synchronously with lacustrine and bog sedimentation and continuing after its termination. The main stages of ore formation are related to volcanic centers differing in age and conjugate hydrothermal systems functioning above a long-living magma chamber.     

Germanium speciation in lignite from a germanium-bearing deposit in Primorye

We studied a number of chemical characteristics in the coals of the Spetsugli germanium-bearing area of the Pavlovskoe coalfield in southern Primorye. It was found that the coals show variable contents of ash, extractable organic matter (OM), and germanium. No less than 60% germanium in the coals are bound to mobile OM, including 25–60% in complex compounds of humic acids and 8–39% in the low-molecular-weight fraction of OM not precipitated by acids. It was shown that germanium can be partly accumulated in coals as organic compounds owing to the dissolution of the mineral forms of germanium by humic acids.     

Geologic structure of Western Primorye: Structuring dynamics

The first data are reported on the structuring dynamics of Western Primorye. The analysis of the structural parageneses of the least studied macro- and mesolevels of the arrangement of the geologic space allowed us to distinguish three sequentially superposed structural patterns (parageneses), each of which was formed by its own stress field during separate geodynamic periods: the Late Proterozoic-Early Paleozoic, the Middle-Late Paleozoic, and the Mesozoic-Cenozoic. During the first two episodes of geodynamic activation (Late Proterozoic-Early Paleozoic), the main compression axis was oriented longitudinally. The first episode was characterized by the formation of a thrust-fold structural pattern. The second episode resulted in the superposition of the meridional riftogenic structures and, respectively, in the pull-apart normal-fault segmentation of the crystalline basement into mainly longitudinal blocks, which partially coincide with the previously distinguished terranes. During the latitudinal compression and oblate deformation that predominanted during the Middle-Late Paleozoic geodynamic period, the down-thrown and uplifted blocks were transformed into depressions and arches, respectively. The depressions were filled with Paleozoic sediments, while the primary rocks in the arches experienced granitization with the formation of two granitic complexes that joined terranes. The granites are characterized by shadow and shear-type fold and pseudofolded forms. The Mesozoic-Cenozoic period governed by NNW compression is divided into the Triassic-Jurassic, Early Cretaceous, and Tertiary tectonic episodes. During the Triassic-Jurassic period, the ENE-trending narrow arches and depressions were formed by warping. The arches accumulated granitized rocks, while the depressions were compensated for by the Early-Late Triassic sedimentary-volcanogenic sediments. All these processes led to the formation of structural complexes that joined and overlapped older complexes of meridional blocks (terranes) across the strike. Two subsequent Mesozoic-Cenozoic episodes manifested themselves in the discrete formation of coal-bearing depressions due to the NNW compression and ENE extension of the warping products.