scholarly journals Strontium and 87Sr/86Sr isotopic ratio of ground brines in the northeastern Angara-Lena artesian basin

2021 ◽  
Vol 44 (2) ◽  
pp. 98-105
Author(s):  
L. P. Alekseeva ◽  
S. V. Alekseev
Keyword(s):  
Isotopic Composition ◽  
High Salinity ◽  
Isotopic Ratio ◽  
Sedimentary Basins ◽  
Formation Processes ◽  
Salt Composition ◽  
Strontium Content ◽  
Mass Spectrometers ◽  
Ionic Salt

The purpose of this study is to identify the major formation processes of the ionic and isotopic composition of chloride brines in the sedimentary basins of the Siberian platform. The object and subject of research are deep-seated strong, very strong and extremely saturated brines as well as their strontium content and the ratio of Sr stable isotopes. The groundwater ionic-salt composition was determined by traditional methods (titrimetric, gravimetric, flame photometry), the 87Sr/86Sr isotopic ratio was measured using mass-spectrometers (Irkutsk, Russia and Canada). The brines lying at the depth of 1500–3000 m were tapped and classified into saline and subsalt hydrogeological formations. Their feature is high salinity (385–530 g/L) and high content of strontium (2.3–7 g/L). The 87Sr/86Sr isotopic ratio ranges from 0.708 to 0.713062. By isotopic composition most of the brine samples are close to the waters of the Vendian-Cambrian paleoocean. However, some brine samples from the subsalt part of the sedimentary section of the basin are significantly enriched in the isotope 87Sr compared to the paleoocean waters and other samples. It could be due to the substantial input of 87Sr into the brines during the long-term interaction of groundwater with the host Lower Cambrian sandstones.

scholarly journals Strontium isotopic ratio in brines from the north-east of the Angara-Lenskiy artesian basin

2019 ◽  
Vol 98 ◽  
pp. 12001
Author(s):  
Sergey Alexeev ◽  
Ludmila Alexeeva ◽  
Orfan Shouakar-Stash
Keyword(s):  
Isotopic Composition ◽  
High Salinity ◽  
Isotopic Ratio ◽  
Oil Field ◽  
Rock Interaction ◽  
Artesian Basin ◽  
Terrigenous Sediments ◽  
North East ◽  
The North ◽  
Water Rock Interaction

The Sr isotopic composition was measured in a number of samples of highly concentrated oil-field brines from the Angara-Lenskiy artesian basin. The brines are contained in the salt-bearing and subsalt-bearing hydrogeological formations at a depth of 1,500-3,000 m. They have high salinity (385-530 g/L) and high Sr content (2.3-7.0 mg/L). The 87Sr/86Sr ratio ranges from 0.70800 to 0.713062. Most brine samples exhibit an isotopic composition similar to Vendian-Cambrian paleoocean water, however several samples from the Yaraktinskiy horizon are significantly more radiogenic than others. It suggests that a considerable amount of 87Sr is likely to have been carried from terrigenous sediments due to a water-rock interaction.

Monitoring and quantitative evaluation of Faraday cup deterioration in a thermal ionization mass spectrometer using multidynamic analyses of laboratory standards

2021 ◽  
Author(s):  
Yankun Di ◽  
Zefeng Li ◽  
Yuri Amelin
Keyword(s):  
Isotopic Ratio ◽  
Ionization Mass ◽  
Mass Spectrometers ◽  
Faraday Cup ◽  
Long Term Stability ◽  
Isotopic Analyses ◽  
Thermal Ionization Mass Spectrometer ◽  
Cross Calibration ◽  
Multiple Detectors

Accurate and precise isotopic ratio determinations using multi-collector (MC) mass spectrometers rely on accurate cross-calibration and long-term stability of the efficiencies of the multiple detectors. Isotopic analyses at part per...

SATELLITE DATA FOR INVESTIGATION OF RECENT STATE AND PROCESSES IN THE SIVASH BAY

2017 ◽  
Author(s):  
Ekaterina Shchurova ◽  
Ekaterina Shchurova ◽  
Rimma Stanichnaya ◽  
Rimma Stanichnaya ◽  
Sergey Stanichny ◽  
...  
Keyword(s):  
Satellite Data ◽  
Water Exchange ◽  
High Salinity ◽  
Meteorological Data ◽  
Sea Surface ◽  
Azov Sea ◽  
Seasonal Wind ◽  
Ice Regime ◽  
Very High

Sivash bay is the shallow-water lagoon of the Azov Sea. Restricted water exchange and high evaporation form Sivash as the basin with very high salinity. This factor leads to different from the Azov Sea thermal and ice regimes of Sivash. Maine aim of the study presented to investigate recent state and changes of the characteristics and processes in the basin using satellite data. Landsat scanners TM, ETM+, OLI, TIRS together with MODIS and AVHRR were used. Additionally NOMADS NOAA and MERRA meteorological data were analyzed. The next topics are discussed in the work: 1. Changes of the sea surface temperature, ice regime and relation with salinity. 2. Coastal line transformation – long term and seasonal, wind impact. 3. Manifestation of the Azov waters intrusions through the Arabat spit, preferable wind conditions.

The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis

1984 ◽  
Vol 64 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Patricia C. Almada-Villela
Keyword(s):  
Growth Rate ◽  
Mytilus Edulis ◽  
High Salinity ◽  
Shell Growth ◽  
Experimental Period ◽  
Gradual Decline ◽  
Poor Growth ◽  
Term Response ◽  
Better Than

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.

scholarly journals Bone Regeneration by Novel Bioactive Glasses Containing Strontium and/or Magnesium: A Preliminary In-Vivo Study

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2223 ◽  
Author(s):  
Devis Bellucci ◽  
Valeria Cannillo ◽  
Alexandre Anesi ◽  
Roberta Salvatori ◽  
Luigi Chiarini ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Formation Processes ◽  
Complete Dissolution ◽  
In Vitro Bioactivity ◽  
Bioactive Glasses ◽  
Beneficial Effects ◽  
Glass Dissolution

In this work, a set of novel bioactive glasses have been tested in vivo in an animal model. The new compositions, characterized by an exceptional thermal stability and high in vitro bioactivity, contain strontium and/or magnesium, whose biological benefits are well documented in the literature. To simulate a long-term implant and to study the effect of the complete dissolution of glasses, samples were implanted in the mid-shaft of rabbits’ femur and analyzed 60 days after the surgery; such samples were in undersized powder form. The statistical significance with respect to the type of bioactive glass was analyzed by Kruskal–Wallis test. The results show high levels of bone remodeling, several new bone formations containing granules of calcium phosphate (sometimes with amounts of strontium and/or magnesium), and the absence of adverse effects on bone processes due to the almost complete glass dissolution. In vivo results confirming the cell culture outcomes of a previous study highlighted that these novel bioglasses had osteostimulative effect without adverse skeletal reaction, thus indicating possible beneficial effects on bone formation processes. The presence of strontium in the glasses seems to be particularly interesting.

scholarly journals On the isotopic composition of precipitation in tropical stations (*).

1985 ◽  
Vol 15 (1-2) ◽  
pp. 121-140 ◽  
Author(s):  
Roberto Gonfiantini
Keyword(s):  
Isotopic Composition ◽  
Water Vapour ◽  
Seasonal Variations ◽  
Pacific Islands ◽  
Continental Effect ◽  
The Mean

Some of the trends and characteristics of the isotopic composition oh precipitation in tropical stations are discussed. Stations in small Pacific islands show a variation with latitude, with lower 8-values between 15°N and 1S°S and higher values at higher. Inland stations are depleted in heavy isotopes with respect to coastal stations but sometimes this continental effect is rather complex, as f,or instance in África. Mean monthly 8-values show a remarkable correlation with the amount of precipitation, but the slope variations do not show a clear dependence on the mean long term 8-value,as should be expected theoretically. In Southern American stations the seasonal variations of the meanmonthly 5-values are correlated and they are greater in inland stations due to con-tinentaly. The possible effects of recycling of water vapour by evapotranspiration are also discussed.

scholarly journals Land subsidence and hydrodynamic compaction of sedimentary basins

1998 ◽  
Vol 2 (2/3) ◽  
pp. 159-171 ◽  
Author(s):  
H. Kooi ◽  
J. J. de Vries
Keyword(s):  
Response Time ◽  
Land Subsidence ◽  
Sedimentary Basins ◽  
Sediment Loading ◽  
Dimensional Model ◽  
One Dimensional ◽  
Model Equations ◽  
Sediment Layers ◽  
The Relationship

Abstract. A one-dimensional model is used to investigate the relationship between land subsidence and compaction of basin sediments in response to sediment loading. Analysis of the model equations and numerical experiments demonstrate quasi-linear systems behaviour and show that rates of land subsidence due to compaction: (i) can attain a significant fraction (>40%) of the long-term sedimentation rate; (ii) are hydrodynamically delayed with respect to sediment loading. The delay is controlled by a compaction response time τc that can reach values of 10-5-107 yr for thick shale sequences. Both the behaviour of single sediment layers and multiple-layer systems are analysed. Subsequently the model is applied to the coastal area of the Netherlands to illustrate that lateral variability in compaction-derived land subsidence in sedimentary basins largely reflects the spatial variability in both sediment loading and compaction response time. Typical rates of compaction-derived subsidence predicted by the model are of the order of 0.1 mm/yr but may reach values in excess of 1 mm/yr under favourable conditions.

scholarly journals Stable isotopic composition of top consumers in Arctic cryoconite holes: revealing divergent roles in a supraglacial trophic network

2021 ◽  
Vol 18 (5) ◽  
pp. 1543-1557
Author(s):  
Tereza Novotná Jaroměřská ◽  
Jakub Trubač ◽  
Krzysztof Zawierucha ◽  
Lenka Vondrovicová ◽  
Miloslav Devetter ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Isotopic Ratio ◽  
Isotopic Fractionation ◽  
Mechanistic Explanation ◽  
High Arctic ◽  
Biologically Active ◽  
Glacier Surface ◽  
Stable Isotopic Composition ◽  
Stable Isotopic ◽  
Trophic Network

Abstract. Arctic cryoconite holes represent highly biologically active aquatic habitats on the glacier surface characterized by the dynamic nature of their formation and functioning. The most common cryoconite apex consumers are the cosmopolitan invertebrates – tardigrades and rotifers. Several studies have highlighted the potential relevance of tardigrades and rotifers to cryoconite holes' ecosystem functioning. However, due to the dominant occurrence of prokaryotes, these consumers are usually out of the major scope of most studies aimed at understanding biological processes on glaciers. The aim of this descriptive study is to present pioneering data on isotopic composition of tardigrades, rotifers and cryoconite from three High Arctic glaciers in Svalbard and discuss their role in a cryoconite hole trophic network. We found that tardigrades have lower δ15N values than rotifers, which indicates different food requirements or different isotopic fractionation of both consumers. The δ13C values revealed differences between consumers and organic matter in cryoconite among glaciers. However, the mechanistic explanation of these variations requires further investigation focused on the particular diet of cryoconite consumers and their isotopic ratio. Our study introduces the first observation of carbon and nitrogen stable isotopic composition of top consumers in cryoconite holes analysed by an improved method for cryoconite sample processing, paving the way for further studies of the supraglacial trophic network.

scholarly journals Salinity Stress Responses and Adaptation Mechanisms in Eukaryotic Green Microalgae

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1657 ◽  
Author(s):  
Prateek Shetty ◽  
Margaret Mukami Gitau ◽  
Gergely Maróti
Keyword(s):  
Stress Responses ◽  
High Salinity ◽  
Freshwater Algae ◽  
Short Term ◽  
Adaptation Mechanisms ◽  
Fundamental Research ◽  
Ionic Imbalance ◽  
Compare And Contrast ◽  
Harsh Conditions

High salinity is a challenging environmental stress for organisms to overcome. Unicellular photosynthetic microalgae are especially vulnerable as they have to grapple not only with ionic imbalance and osmotic stress but also with the generated reactive oxygen species (ROS) interfering with photosynthesis. This review attempts to compare and contrast mechanisms that algae, particularly the eukaryotic Chlamydomonas microalgae, exhibit in order to immediately respond to harsh conditions caused by high salinity. The review also collates adaptation mechanisms of freshwater algae strains under persistent high salt conditions. Understanding both short-term and long-term algal responses to high salinity is integral to further fundamental research in algal biology and biotechnology.

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