Hydrochemical and Hydroacoustic Investigation of the Yugama Acid Crater Lake, Kusatsu-Shirane, Japan

The gases dissolved in the waters of volcanic lakes can present a serious hazard if the physical-chemical conditions change due to variations in the supply of magmatic gases. The monitoring of gases such as CO2 and He help us understand the degassing process and their connection with magmatic/hydrothermal system. One of the most acidic volcanic lakes on the planet is the Yugama, on Kusatsu Shirane volcano (Japan). We report the results of an interdisciplinary study carried out in August 2013 at Yugama consisting of the first estimation of rate of diffuse CO2 emission, the chemical and isotopic analysis of water and dissolved gases in samples from vertical lake profiles, and an echo-sounding survey. The lake water has an average temperature of 24-25°C, pH 1.01, concentrations of SO42- between 1,227 and 1,654 mgL−1 and Cl− between 1,506 and 2,562 mgL−1, with gas bubbling at several locations and floating sulfur globules with sulfide inclusions. A total of 66 CO2 efflux measurements were taken at the lake surface by means of the floating accumulation chamber method to estimate the diffuse CO2 output from the studied area. CO2 efflux values ranged from 82 up to 25,800 g m−2 d−1. Estimation of the diffuse CO2 emission at Yaguma Crater Lake was 30 ± 12 t d−1. Normalized CO2 emission rate (assuming an area of 0.066 km2) was 454 t km−2 d−1, a value within the range of acid volcanic lakes. Vertical profiles of major ions and dissolved gases showed variations with increases in ion content and dissolved CO2 and He with depth. Acoustic imaging shows the presence of intense bubbling and provides important information on the bathymetry of the lake. The 50–200 kHz echograms exhibit frequent vertical plumes of rising gas bubbles. Within the crater-lake, three circular submarine vents have been identified showing flares due to a significant activity of sublacustrine emissions. This work shows the first data of diffuse CO2 degassing, dissolved gases in water and echosounding (ES) from Yugama Crater Lake. Periodic hydrogeochemical and hydroacoustic surveys at Yugama Crater Lakemay thus help to document changes in the state of activity of this high-risk volcanic area.

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Hydrogeology and hydrogeochemistry of an alkaline volcanic area: the NE Mt. Meru slope (East African Rift – Northern Tanzania)

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-8255-2011 ◽

2011 ◽

Vol 8 (5) ◽

pp. 8255-8289 ◽

Cited By ~ 1

Author(s):

G. Ghiglieri ◽

D. Pittalis ◽

G. Cerri ◽

G. Oggiano

Keyword(s):

Major Ions ◽

Volcanic Rocks ◽

Volcanic Area ◽

East African ◽

Geochemical Composition ◽

Fine Grained ◽

Physico Chemical ◽

Northern Tanzania ◽

Hydraulic Gradients ◽

African Rift

Abstract. The objective of this study is to analyze the geochemical conditions associated with the presence of fluoride (F−) in the groundwater of an area of Northern Tanzania. The studied aquifers are composed of volcanic rocks such as phonolitic and nephelinitic lavas, basalts, lahars of various ages and mantling ash. Sedimentary rocks consisting of fine-grained alluvial and lacustrine deposits occur as well. Samples collected from springs, borehole and surface water, during two monitoring surveys, were analyzed for the various physico-chemical and isotopic parameters. The geochemical composition of water is typically sodium bicarbonate. High values of F− (up to 68 mg l−1) were recorded. The highest values of fluoride agreed with the highest values of pH, sodium and bicarbonate. Dissolution of major ions, exchange processes and precipitation of Ca2+ from super-saturated solutions joined with the local permeability and hydraulic gradients, control the fluoride mobilization and the contamination of the area.

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Contrasting physical and chemical conditions of two springs fed by active rock glaciers

10.22541/au.160872486.67141574/v1 ◽

2020 ◽

Author(s):

Stefano Brighenti ◽

Michael Engel ◽

Monica Tolotti ◽

Maria Bruno ◽

Geraldene Wharton ◽

...

Keyword(s):

Trace Elements ◽

Water Temperature ◽

Major Ions ◽

Quantitative Description ◽

European Alps ◽

Rock Glacier ◽

Rainfall Events ◽

Rock Glaciers ◽

Chemical Conditions ◽

Physical And Chemical

Rock glaciers are increasingly influencing the hydrology and water chemistry of Alpine catchments, with important implications for drinking water quality and ecosystem health under a changing climate. During summers of 2017 - 2019, we monitored the physical and chemical conditions of springs emerging from two active rock glaciers (ZRG and SRG) with distinct geomorphological settings in the Eastern Italian Alps (Solda/Sulden catchment). Both springs had constantly cold waters (1.4 ± 0.1 °C), and their ionic composition was dominated by SO42-, HCO3-, Ca2+ and Mg2+. Concentrations of major ions and trace elements, and values of water isotopes (δ18O, δ2H), increased towards autumn with an asymptotic trend at SRG, and a positive unimodal pattern at ZRG, where concentrations peaked 60 - 80 days after the end of the snowmelt. Wavelet analysis on electrical conductivity (EC) and water temperature records revealed daily cycles only at SRG, and significant weekly/biweekly fluctuations at both springs attributable to oscillations of meteorological conditions. Several rainfall events triggered a transient (0.5 - 2 hrs) EC drop and water temperature rise (dilution and warming) at SRG, whereas only intense rainfall events occasionally increased EC at ZRG (solute enrichment and thermal buffering), with a long-lasting effect (6 - 48 hrs). Our results, supported by a limited but emerging literature, suggest that: i) the distinctive composition of the bedrock drives different concentrations of major ions and trace elements in rock glacier springs; ii) pond-like and stream-like springs have distinct fluctuations of water parameters at different timescales; iii) peaks of EC/solute concentrations indicate a seasonal window of major permafrost thaw for rock glaciers feeding pond-like springs. These results provide a first quantitative description of the hydrological seasonality in rock glacier outflows, and their hydrochemical response to precipitation events, bringing relevant information for water management in the European Alps under climate change.

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Uniform “water” content in quartz phenocrysts from silicic pyroclastic fallout deposits – implications on pre-eruptive conditions

European Journal of Mineralogy ◽

10.5194/ejm-33-571-2021 ◽

2021 ◽

Vol 33 (5) ◽

pp. 571-589

Author(s):

Mátyás Hencz ◽

Tamás Biró ◽

István János Kovács ◽

Roland Stalder ◽

Károly Németh ◽

...

Keyword(s):

Water Content ◽

Water Saturation ◽

Narrow Range ◽

Taupo Volcanic Zone ◽

Volcanic Complex ◽

Volcanic Area ◽

Hydroxyl Content ◽

Magmatic Plumbing System ◽

Structural Hydroxyl ◽

Chemical Conditions

Abstract. Structural hydroxyl content of volcanic quartz phenocrysts was investigated with unpolarized Fourier-transform infrared spectroscopy. The phenocrysts originated from five pyroclastic fallout deposits from the Bükk Foreland Volcanic Area (BFVA), Hungary, and two from the AD 1314 Kaharoa eruption (KH eruption), Okataina Volcanic Complex (Taupo Volcanic Zone), New Zealand. All investigated quartz populations contain structural hydroxyl content in a narrow range with an average of 9.3 (±1.7) wt ppm. The earlier correlated horizons in the BFVA had the same average structural hydroxyl content (within uncertainty). Thus, it can be concluded that the structural hydroxyl content does not depend on the geographical distance of outcrops of the same units or the temperature or type of the covering deposit. The rare outlier values and similar structural hydroxyl contents show that the fallout horizons cooled fast enough to retain their original structural hydroxyl content. The similarity of the structural hydroxyl contents may be the result of similar P, T, and x (most importantly H2O and the availability of other monovalent cations) conditions in the magmatic plumbing system just before eruption. Therefore, we envisage common physical–chemical conditions, which set the structural hydroxyl content in the quartz phenocrysts and, consequently, the water content of the host magma (∼ 5.5 wt %–7 wt % H2O) in a relatively narrow range close to water saturation.

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Nitrogen, Carbon, and Sulfur Metabolism in NaturalThioploca Samples

Applied and Environmental Microbiology ◽

10.1128/aem.65.7.3148-3157.1999 ◽

1999 ◽

Vol 65 (7) ◽

pp. 3148-3157 ◽

Cited By ~ 171

Author(s):

Sandra Otte ◽

J. Gijs Kuenen ◽

Lars P. Nielsen ◽

Hans W. Paerl ◽

Jakob Zopfi ◽

...

Keyword(s):

Elemental Sulfur ◽

Sulfur Metabolism ◽

Sulfide Oxidation ◽

Significant Activity ◽

Acetate Incorporation ◽

Fixation Rate ◽

Sulfate Production ◽

Sulfur Globules ◽

High Concentrations ◽

A Minor

ABSTRACT Filamentous sulfur bacteria of the genus Thioplocaoccur as dense mats on the continental shelf off the coast of Chile and Peru. Since little is known about their nitrogen, sulfur, and carbon metabolism, this study was undertaken to investigate their (eco)physiology. Thioploca is able to store internally high concentrations of sulfur globules and nitrate. It has been previously hypothesized that these large vacuolated bacteria can oxidize sulfide by reducing their internally stored nitrate. We examined this nitrate reduction by incubation experiments of washed Thioplocasheaths with trichomes in combination with 15N compounds and mass spectrometry and found that these Thioplocasamples produce ammonium at a rate of 1 nmol min−1 mg of protein−1. Controls showed no significant activity. Sulfate was shown to be the end product of sulfide oxidation and was observed at a rate of 2 to 3 nmol min−1 mg of protein−1. The ammonium and sulfate production rates were not influenced by the addition of sulfide, suggesting that sulfide is first oxidized to elemental sulfur, and in a second independent step elemental sulfur is oxidized to sulfate. The average sulfide oxidation rate measured was 5 nmol min−1 mg of protein−1 and could be increased to 10.7 nmol min−1 mg of protein−1 after the trichomes were starved for 45 h. Incorporation of14CO2 was at a rate of 0.4 to 0.8 nmol min−1 mg of protein−1, which is half the rate calculated from sulfide oxidation. [2-14C]acetate incorporation was 0.4 nmol min−1 mg of protein−1, which is equal to the CO2 fixation rate, and no 14CO2 production was detected. These results suggest that Thioploca species are facultative chemolithoautotrophs capable of mixotrophic growth. Microautoradiography confirmed that Thioploca cells assimilated the majority of the radiocarbon from [2-14C]acetate, with only a minor contribution by epibiontic bacteria present in the samples.

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Hydrogeology and hydrogeochemistry of an alkaline volcanic area: the NE Mt. Meru slope (East African Rift – Northern Tanzania)

Hydrology and Earth System Sciences ◽

10.5194/hess-16-529-2012 ◽

2012 ◽

Vol 16 (2) ◽

pp. 529-541 ◽

Cited By ~ 32

Author(s):

G. Ghiglieri ◽

D. Pittalis ◽

G. Cerri ◽

G. Oggiano

Keyword(s):

Major Ions ◽

Volcanic Rocks ◽

Volcanic Area ◽

East African ◽

Geochemical Composition ◽

Fine Grained ◽

Physico Chemical ◽

Northern Tanzania ◽

Hydraulic Gradients ◽

African Rift

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Hydrochemical and Isotopic Investigation of the Groundwater from Wajid Aquifer in Wadi Al-Dawasir, Southern Saudi Arabia

Water ◽

10.3390/w13131855 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1855

Author(s):

Mohammed Benaafi ◽

Abdulaziz Al-Shaibani

Keyword(s):

Saudi Arabia ◽

Chemical Composition ◽

Ion Exchange ◽

Major Ions ◽

Saline Water ◽

Isotopic Analysis ◽

Unconfined Aquifer ◽

Hydrochemical Processes ◽

Groundwater Samples ◽

Confined Aquifers

The Wajid aquifer is considered the main source of water for drinking and irrigation in Wadi Al-Dawasir and Najran, the southern region of Saudi Arabia. This aquifer has been used since the 1960s, and due to the expansion in agricultural activities, the aquifer has been overexploited. The study aims to understand the origin, hydrochemical processes of the groundwater in the shallow unconfined, deep unconfined, and confined parts of the Wajid aquifer in the Wadi Al-Dawasir area. In-situ hydrochemical parameters (pH, temperature, EC, and TDS) were measured in the field, and groundwater samples were collected for major ions and stable isotopes (2H and 18O) measurements in the laboratory. The results show that the groundwater in shallow unconfined, and confined aquifers are of two types; Cl.SO4-Ca. Na and Cl.SO4-Na. Ca; however, groundwater in deep, unconfined aquifers is characterized as HCO3-Ca. Na, and Cl. HCO3-Ca. Na; types of groundwater. The isotopic analysis results reveal that all groundwater samples have values of δ18Oand δ2Hclose to the local and global meteoric water lines, indicating the meteoric origin of Wajid groundwater. Three major hydrochemical processes, including rock weathering, ion exchange, and evaporation, have been identified as key controls on the chemical composition of water in the studied aquifer. The evaporation and ion exchange processes have more influence on the chemical composition of groundwater in the shallow unconfined and confined aquifers. On the contrary, weathering of carbonate minerals affected more the chemistry of groundwater in a deep unconfined aquifer. The unconfined section of the Wajid aquifer shows a reverse pattern of salinity with higher salinity in the recharge area, which is most probably related to the return irrigation water and leaching of salty soil. The open fractures in the upper part of Wajid sandstone most likely act as conduits to percolated saline water to the Wajid aquifer.

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GEOHYDROTHERMAL MODEL OF ARJUNO, WELIRANG AND PENANGGUNGAN VOLCANOES EAST JAVA, INDONESIA

PENELITIAN DAN KARYA ILMIAH ◽

10.25105/pdk.v2i1.2457 ◽

2018 ◽

Vol 2 (1) ◽

pp. 37

Author(s):

Untung Sumotarto ◽

F. Hendrasto ◽

Wibagiyo Wibagiyo

Keyword(s):

Geothermal Energy ◽

Meteoric Water ◽

Volcanic Rocks ◽

Isotopic Analysis ◽

Igneous Rocks ◽

Volcanic Area ◽

Maturity Level ◽

Energy Potential ◽

Potential Resource ◽

Water Springs

Indonesia is a country having a high geothermal energy potential. The geothermal energy in Java island, as a volcanic row island, has been explored and produced. One of the area that has not been produced is volcanic area around Arjuno, Welirang and Penanggungan (AWP) located in East Java. Geochemical survey has been performed to explore a more detailed objective in exploring the potential resource of geothermal energy of this area. Chemical and isotopic analysis shows the maturity level of waters taken from water springs in the area. The immature water from the water springs is interpreted coming mostly from meteoric water which flows quite fast forming water springs around the area. Geohydrothermally, the water flows through porous and permeable volcanic rocks that receive heat from igneous rocks existing together in the area. The igneous rocks are flowing heat conductively from magma below the AWP volcanoes.

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Hydrogeochemical Characterization of a Warm Spring System in a Carbonate Mountain Range of the Eastern Julian Alps, Slovenia

Water ◽

10.3390/w12051427 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1427 ◽

Cited By ~ 1

Author(s):

Luka Serianz ◽

Nina Rman ◽

Mihael Brenčič

Keyword(s):

Thermal Water ◽

Major Ions ◽

Isotopic Analysis ◽

Chemical Components ◽

Circulation System ◽

Mountain Range ◽

Fresh Groundwater ◽

Deep Circulation ◽

Hydrogeochemical Characterization ◽

Meteoric Precipitation

The Alps represent an area where many deep groundwater circulations occur as thermal springs. In the Bled case study, the thermal water temperature, at it is discharged to the surface, is between 19–23 °C. In order to determine the extent (e.g., geometry) and the origin of the pronounced deep circulation system in the Bled area, chemical and isotopic measurements of waters from different hydrogeological systems were performed (e.g., surface water, thermal water, fresh groundwater). Hydrogeochemical methods were used to tie together the above-mentioned parameters. The results have shown that thermal outflow in Bled is determined by the presence of a deep-water circulation system, where the dissolution of carbonates minerals is the main hydrogeochemical process affecting chemical components of natural water flow. The correlation of the major ions suggests that the recharge area is represented by both limestone and dolomite rocks. Moreover, the results of δ18O and δ2H of all samples indicate that the recharge is mainly meteoric precipitation. The recharge altitude was estimated for two sampled fresh groundwater springs. The isotopic compositions of those two springs suggest the range from δ18O = −8.68‰, δ2H = −57.4‰ at an elevation of 629 m to δ18O = −9.30‰, δ2H = −60.1‰ at an elevation of 1216 m. The isotopic analysis has confirmed that the thermal water recharges from altitudes of 1282–1620 m a.s.l.

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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Laboratory and in-situ analysis of comet dust

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102122 ◽

1988 ◽

Vol 46 ◽

pp. 8-9

Author(s):

D.E. Brownlee ◽

A.L. Albee

Keyword(s):

Electron Microscopy ◽

Solar System ◽

Laboratory Study ◽

Isotopic Analysis ◽

Building Blocks ◽

Sem Analysis ◽

Early Solar System ◽

Cometary Material ◽

Comet Dust

Comets are primitive, kilometer-sized bodies that formed in the outer regions of the solar system. Composed of ice and dust, comets are generally believed to be relic building blocks of the outer solar system that have been preserved at cryogenic temperatures since the formation of the Sun and planets. The analysis of cometary material is particularly important because the properties of cometary material provide direct information on the processes and environments that formed and influenced solid matter both in the early solar system and in the interstellar environments that preceded it.The first direct analyses of proven comet dust were made during the Soviet and European spacecraft encounters with Comet Halley in 1986. These missions carried time-of-flight mass spectrometers that measured mass spectra of individual micron and smaller particles. The Halley measurements were semi-quantitative but they showed that comet dust is a complex fine-grained mixture of silicates and organic material. A full understanding of comet dust will require detailed morphological, mineralogical, elemental and isotopic analysis at the finest possible scale. Electron microscopy and related microbeam techniques will play key roles in the analysis. The present and future of electron microscopy of comet samples involves laboratory study of micrometeorites collected in the stratosphere, in-situ SEM analysis of particles collected at a comet and laboratory study of samples collected from a comet and returned to the Earth for detailed study.

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