Gas monitoring of a hydrothermal-magmatic volcano in a tropical environment: the example of La Soufriere de Guadeloupe (FWI)

2021 ◽  
Author(s):  
Severine Moune ◽  
Roberto Moretti ◽  
Arnaud Burtin ◽  
David Jessop ◽  
Tristan Didier ◽  
...  
Keyword(s):  
Hydrothermal System ◽  
Tropical Environment ◽  
Chemical Compositions ◽  
Gas Emissions ◽  
Mass Fluxes ◽  
Groundwater Circulation ◽  
Volcanic Seismicity ◽  
Long Term Trends ◽  
The One ◽  
Fumarolic Gas

<p>Fumarolic gas survey of dormant volcanoes is fundamental because the compositional and flux changes in gas emissions are recognised signals of unrest and may even be precursors of eruptions on several dormant volcanoes in hydrothermal unrest [1-5].</p><p>Here we report on the chemical compositions (CO<sub>2</sub>, H<sub>2</sub>S, SO<sub>2</sub>, H<sub>2</sub>) and mass fluxes of fumarolic gas emissions from the low-temperature (from 97° to 104°C) volcanic-hydrothermal system of La Soufrière de Guadeloupe (Lesser Antilles). This present study covers the period 2016 to present, encompassing the peak activity of April 2018. Long-term trends are acquired from both portable MultiGAS measurements (performed monthly) and two permanent MultiGAS stations (4 automated 20’ measurements per day). These MultiGAS data are discussed along with other geochemical and geophysical parameters monitored at OVSG, such as complete fumarole chemistry via Giggenbach bottles, fumarole temperatures, volcanic seismicity and deformation in order to track the deep-sourced magmatic signal contribution compared to the one of the hydrothermal system and detect potential signs of unrest [6].</p><p>Dealing with MultiGAS data from a low-T fumarolic system in a tropical environment is not straightforward due to external forcing effect of meteoric water on gas composition. Hence, interpretation of the observed chemical changes must consider (i) the role of water-gas-rock interactions and gas scrubbing processes by the hydrothermal system and the perched volcanic pond [7], which particularly affect sulphur precipitation and remobilization and (ii) how these processes vary with rainfall and groundwater circulation (i.e. rainy vs non-rainy seasons, extreme events).</p><p>[1] Giggenbach and Sheppard, 1989; [2] Symonds et al., 1994; [3] Hammouya et al., 1998; [4] De Moor et al., 2016; [5] Allard et al., 2014; [6] Moretti et al., submitted; [7] Symonds et al., 2001</p>

scholarly journals A Cross-Sectional Model for West Antarctica

1984 ◽  
Vol 5 ◽  
pp. 95-99 ◽  
Author(s):  
B. J. McInnes ◽  
W. F. Budd
Keyword(s):  
Ross Sea ◽  
Dynamic State ◽  
Ice Thickness ◽  
Cross Sectional ◽  
West Antarctic Ice Sheet ◽  
Ross Ice Shelf ◽  
West Antarctic ◽  
Mass Fluxes ◽  
Ice Stream B ◽  
The One

The dynamic state of the West Antarctic ice sheet has been termed the grand problem of glaciology. An attempt is presented to assess it by simulating the observed ice thickness and ice velocities along a cross-section from ice stream B (Ross Sea) to Pine Island Glacier (Pine Island Bay) with a numerical model developed from the one described by Budd and McInnes (1978). A kinematic analysis with topographical and regime data from various sources shows the mass fluxes observed near the grounding line of the Ross Ice Shelf to be of the order expected for steady-state balance. Deformation of the ice accounts for only a small fraction of the observed flow there. Simulations (to be described in detail elsewhere) with the Budd/McInnes surging mechanism can approximate the existing ice thickness as a post-surge feature but fail to reproduce the high balance velocities. Both these velocities and the existing ice-thickness profile are simulated successfully as a state of steady sliding, with parameterizations involving the ice thickness above that corresponding to buoyancy and realistically assumed longitudinal strain-rates. A range of results is presented to illustrate the sensitivity of the simulation to changes in various parameters.

scholarly journals Fluid chemistry of the low temperature hyperalkaline hydrothermal system of Prony Bay (New Caledonia)

2014 ◽  
Vol 11 (20) ◽  
pp. 5687-5706 ◽  
Author(s):  
C. Monnin ◽  
V. Chavagnac ◽  
C. Boulart ◽  
B. Ménez ◽  
M. Gérard ◽  
...  
Keyword(s):  
Low Temperature ◽  
Marine Environment ◽  
Water Samples ◽  
Hydrothermal System ◽  
New Caledonia ◽  
Water Discharge ◽  
The Other ◽  
Chemical Compositions ◽  
Saturation State ◽  
High Ph

Abstract. The terrestrial hyperalkaline springs of Prony Bay (southern lagoon, New Caledonia) have been known since the nineteenth century, but a recent high-resolution bathymetric survey of the seafloor has revealed the existence of numerous submarine structures similar to the well-known Aiguille de Prony, which are also the location of high-pH fluid discharge into the lagoon. During the HYDROPRONY cruise (28 October to 13 November 2011), samples of waters, gases and concretions were collected by scuba divers at underwater vents. Four of these sampling sites are located in Prony Bay at depths up to 50 m. One (Bain des Japonais spring) is also in Prony Bay but uncovered at low tide and another (Rivière des Kaoris spring) is on land slightly above the seawater level at high tide. We report the chemical composition (Na, K, Ca, Mg, Cl, SO4, dissolved inorganic carbon, SiO2(aq)) of 45 water samples collected at six sites of high-pH water discharge, as well as the composition of gases. Temperatures reach 37 °C at the Bain des Japonais and 32 °C at the spring of the Kaoris. Gas bubbling was observed only at these two springs. The emitted gases contain between 12 and 30% of hydrogen in volume of dry gas, 6 to 14% of methane, and 56 to 72% of nitrogen, with trace amounts of carbon dioxide, ethane and propane. pH values and salinities of all the 45 collected water samples range from the seawater values (8.2 and 35 g L−1) to hyperalkaline freshwaters of the Ca-OH type (pH 11 and salinities as low as 0.3 g L−1) showing that the collected samples are always a mixture of a hyperalkaline fluid of meteoric origin and ambient seawater. Cl-normalized concentrations of dissolved major elements first show that the Bain des Japonais is distinct from the other sites. Water collected at this site are three component mixtures involving the high-pH fluid, the lagoon seawater and the river water from the nearby Rivière du Carénage. The chemical compositions of the hyperalkaline endmembers (at pH 11) are not significantly different from one site to the other although the sites are several kilometres away from each other and are located on different ultramafic substrata. The very low salinity of the hyperalkaline endmembers shows that seawater does not percolate through the ultramafic formation. Mixing of the hyperalkaline hydrothermal endmember with local seawater produces large ranges and very sharp gradients of pH, salinity and dissolved element concentrations. There is a major change in the composition of the water samples at a pH around 10, which delimitates the marine environment from the hyperalkaline environment. The redox potential evolves toward negative values at high pH indicative of the reducing conditions due to bubbling of the H2-rich gas. The calculation of the mineral saturation states carried out for the Na-K-Ca-Mg-Cl-SO4-DIC-SiO2-H2O system shows that this change is due to the onset of brucite formation. While the saturation state of the Ca carbonates over the whole pH range is typical of that found in a normal marine environment, Mg- and Mg-Ca carbonates (magnesite, hydromagnesite, huntite, dolomite) exhibit very large supersaturations with maximum values at a pH of around 10, very well marked for the Bain des Japonais, emphasizing the role of water mixing in mineral formation. The discharge of high-pH waters of meteoric origin into the lagoon marine environment makes the hydrothermal system of Prony Bay unique compared to other low temperature serpentinizing environments such as Oman (fully continental) or Lost City (fully marine).

scholarly journals The Chemical Composition of Planetary Nebulae

1968 ◽  
Vol 34 ◽  
pp. 209-223 ◽  
Author(s):  
Lawrence H. Aller ◽  
Stanley J. Czyzak
Keyword(s):  
Chemical Composition ◽  
Planetary Nebulae ◽  
Quantum Mechanical ◽  
Physical Parameters ◽  
Chemical Compositions ◽  
Mechanical Theory ◽  
Gaseous Nebulae ◽  
Quantum Mechanical Theory ◽  
The One

The problem of the determination of the chemical compositions of planetary and other gaseous nebulae constitutes one of the most exasperating problems in astrophysics. On the one hand, the problem appears to be conceptually simple – the mechanisms of excitation of the various lines appear to be well understood and the necessary physical parameters can be obtained by quantum mechanical theory. Yet the task is a difficult one and we want to explore some of the significant features.

Noble gas and stable isotope geochemistry of thermal fluids from Deception Island, Antarctica

2009 ◽  
Vol 21 (3) ◽  
pp. 255-267 ◽  
Author(s):  
Minoru Kusakabe ◽  
Keisuke Nagao ◽  
Takeshi Ohba ◽  
Jung Hun Seo ◽  
Sung-Hyun Park ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Hydrothermal System ◽  
Hot Spring ◽  
Isotope Geochemistry ◽  
Noble Gas ◽  
Deception Island ◽  
Rock Interaction ◽  
Thermal Fluids ◽  
Back Arc ◽  
Fumarolic Gas

AbstractNew stable isotope and noble gas data obtained from fumarolic and bubbling gases and hot spring waters sampled from Deception Island, Antarctica, were analysed to constrain the geochemical features of the island's active hydrothermal system and magmatism in the Bransfield back-arc basin. The 3He/4He ratios of the gases (< 9.8 × 10-6), which are slightly lower than typical MORB values, suggest that the Deception Island magma was generated in the mantle wedge of a MORB-type source but the signature was influenced by the addition of radiogenic 4He derived from subducted components in the former Phoenix Plate. The N2/He ratios of fumarolic gas are higher than those of typical mantle-derived gases suggesting that N2 was added during decomposition of sediments in the subducting slab. The δ13C values of -5 to -6‰ for CO2 also indicate degassing from a MORB-type mantle source. The H2/Ar- and SiO2 geothermometers indicate that the temperatures in the hydrothermal system below Deception Island range from ~150°C to ~300°C. The δD and δ18O values measured from fumarolic gas and hot spring waters do not indicate any contribution of magmatic water to the samples. The major ionic components and δD-δ18O-δ34S values indicate that hot spring waters are a mixture of local meteoric water and seawater. Mn and SiO2 in spring waters were enriched relative to seawater reflecting water-rock interaction at depth.

scholarly journals What is the best temperature-humidity index equation to indicate heat stress in crossbred dairy calves in a tropical environment?

2019 ◽  
Vol 49 (1) ◽  
Author(s):  
Fernanda Gatti de Oliveira Nascimento ◽  
Hellen Cris Pinto Aguiar ◽  
Gustavo Moya Rodrigues ◽  
Ednaldo Carvalho Guimarães ◽  
Mara Regina Bueno de Mattos Nascimento
Keyword(s):  
Heat Stress ◽  
Dew Point ◽  
Tropical Environment ◽  
Dairy Calves ◽  
Sensible Heat ◽  
Dew Point Temperature ◽  
Physiological Variables ◽  
Temperature Humidity Index ◽  
Humidity Index ◽  
The One

ABSTRACT: The aim of this study was to determine among nine temperature-humidity index (THI) equations, the one that best represents the effects of heat stress on crossbred dairy calves reared in a tropical environment. Twelve male and female calves, aged 20 to 60 days, and raised in a tropical pen were evaluated. Respiratory (RR) and heart rates (HR), rectal (RT), body surface (BST), dry bulb (Tdb) and wet bulb (Tbw) temperatures, partial vapor pressure (Pv), relative humidity (RH) and dew point temperature (Tpo) were quantified in the morning and afternoon. Nine THI equations were calculated. The highest correlation between physiological variables and this was used to select the best THI equation. Averages for nine THI equations, Tdb, Twb, Pv, Tdp, RR, HR, RT, and BST were higher in the afternoon than in the morning, whereas that for RH was the opposite. The highest values for RT occurred at temperatures above 26.4°C and when humidity was below 55.5%. The Tdb and Pv correlations with RR (0.697 and 0.707), RT (0.703 and 0.706) and BST (0.818 and 0.817) were significant and positive, whereas the RH correlations with the same physiological variables were significant and negative (-0.622, -0.590 and -0.638, respectively). The best index was the THI sensible heat-based ( T H I = 3.43 + 1.058 x T d b - 0.293 x R H + 0.0164 x T d b x R H + 35.7), which was significantly correlated with RR (r=0.668 and r²=0.446), HR (r=0.259 and r²=0.067), RT (r=0.693 and r²=0.479) and BST (r=0.807 and r²=0.650). In conclusion, the THI sensible heat-based equation best represents the effects of heat stress on crossbred dairy calves reared in a tropical environment.

Effects of Mineral Additives on Chemical Compositions, Microbes and Gas Emissions of Hanwoo Cow Manure

2021 ◽  
Vol 55 (4) ◽  
pp. 95-102
Author(s):  
Young-Ho Joo ◽  
◽  
Seong-Shin Lee ◽  
Hyeon-Tak Noh ◽  
Jeong-Seok Choi ◽  
...  
Keyword(s):  
Chemical Compositions ◽  
Cow Manure ◽  
Gas Emissions ◽  
Mineral Additives

Fortifying Inequality

2020 ◽  
pp. 1-13
Author(s):  
Gus Van Harten
Keyword(s):  
Greenhouse Gas ◽  
Dispute Settlement ◽  
Adult Population ◽  
Foreign Investor ◽  
Global Inequality ◽  
Gas Emissions ◽  
International Protection ◽  
Investor Protections ◽  
The One

In this chapter, foreign investor protections are introduced as a symbol and guarantor of global inequality. Backed by the most powerful adjudicative mechanism in international law, these protections benefit 255,000 people whose combined wealth exceeds that of 80 per cent of the world’s adult population, about four billion people. They lead one to ask if the one hundred companies responsible for most industrial greenhouse gas emissions, for example, are so vulnerable or helpful to others as to deserve extraordinary international protection. Commonplace arguments in favour of investor–state dispute settlement (ISDS) are surveyed and criticized. The promotional role of the ISDS industry of arbitrators, lawyers, and experts, for which ISDS has generated to billions in fees, is also highlighted, focusing on arbitrators whose pro-investor interpretations laid a foundation for the explosion of ISDS.

Long-term Trends in China-Taiwan Relations: Implications for U.S. Taiwan Policy

Asian Survey ◽  
2005 ◽  
Vol 45 (6) ◽  
pp. 970-991 ◽  
Author(s):  
Phillip C. Saunders
Keyword(s):  
United States ◽  
The United States ◽  
Status Quo ◽  
Security Environment ◽  
The Status ◽  
Long Term Trends ◽  
The One ◽  
The Taiwan Strait ◽  
Political Economic

Long-term political, economic, and military trends are reshaping the security environment in the Taiwan Strait in potentially destabilizing ways and undermining the ““one China”” framework. The United States has become more deeply involved in cross-strait relations to maintain stability and preserve the status quo, but this approach may not be sustainable.

Long-Term Trends and Opportunities for Managing Regional Water Supply and Wastewater Greenhouse Gas Emissions

2011 ◽  
Vol 45 (12) ◽  
pp. 5434-5440 ◽  
Author(s):  
Murray R. Hall ◽  
Jim West ◽  
Bradford Sherman ◽  
Joe Lane ◽  
David de Haas
Keyword(s):  
Water Supply ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Gas Emissions ◽  
Long Term Trends ◽  
Regional Water

scholarly journals Monitoring the response of volcanic CO2 emissions to changes in the Los Humeros hydrothermal system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anna Jentsch ◽  
Walter Duesing ◽  
Egbert Jolie ◽  
Martin Zimmer
Keyword(s):  
Fluid Flow ◽  
Hydrothermal System ◽  
Damage Zone ◽  
Inverse Correlation ◽  
Normal Fault ◽  
Atmospheric Effects ◽  
Volcanic Complex ◽  
Geothermal Resources ◽  
Gas Emissions ◽  
Soil Degassing

AbstractCarbon dioxide is the most abundant, non-condensable gas in volcanic systems, released into the atmosphere through either diffuse or advective fluid flow. The emission of substantial amounts of CO2 at Earth’s surface is not only controlled by volcanic plumes during periods of eruptive activity or fumaroles, but also by soil degassing along permeable structures in the subsurface. Monitoring of these processes is of utmost importance for volcanic hazard analyses, and is also relevant for managing geothermal resources. Fluid-bearing faults are key elements of economic value for geothermal power generation. Here, we describe for the first time how sensitively and quickly natural gas emissions react to changes within a deep hydrothermal system due to geothermal fluid reinjection. For this purpose, we deployed an automated, multi-chamber CO2 flux monitoring system within the damage zone of a deep-rooted major normal fault in the Los Humeros Volcanic Complex (LHVC) in Mexico and recorded data over a period of five months. After removing the atmospheric effects on variations in CO2 flux, we calculated correlation coefficients between residual CO2 emissions and reinjection rates, identifying an inverse correlation of ρ = − 0.51 to − 0.66. Our results indicate that gas emissions respond to changes in reinjection rates within 24 h, proving an active hydraulic communication between the hydrothermal system and Earth’s surface. This finding is a promising indication not only for geothermal reservoir monitoring but also for advanced long-term volcanic risk analysis. Response times allow for estimation of fluid migration velocities, which is a key constraint for conceptual and numerical modelling of fluid flow in fracture-dominated systems.

Sign in / Sign up

Export Citation Format

Share Document