Gaseous Emanations Research Articles

Uptake of gaseous thallium, tellurium, vanadium and molybdenum into anhydrous alum, Lascar volcano fumaroles, Chile

Formation of secondary sulfate minerals during the reaction between volcanic gases and rocks modulates the composition and flux of gaseous emanations. We report on the sub-surface formation of anhydrous alum (MI MIII (XVIO4)2 with MI = NH4+, Na+, K+; MIII = Al3+, Fe3+ and XVI = S6+, Mo6+) in the 330 °C fumaroles of the Lascar volcano (Chile). The alum occurs as a few millimetres thick crust that grew internally by two-way diffusion of reaction gases and diffusive influx of rock cations within the crust. The average growth rate is estimated at ca. 0.3 μm/day, based on the 19-year-long activity of the degassing fracture hosting the crust. The growth rate is controlled by the slow migration of the rock cations and decreases towards crust rim. The crust selectively concentrates Tl, V and Te (thousands of μg/g) and to a lesser extent Mo (hundreds of μg/g). The uptake of gaseous Tl, V and Mo is due to the possibility for these elements to enter the MI, MIII and XVI sites of alum, respectively. The process of Te uptake must be related to the incorporation of Tl and V with which Te tightly correlates. Extensive substitution of Tl, V and Te occurs at the surface of the crust where the supply of rock cations is the lowest. Such surface enrichment does not occur for Mo, because Mo substitutes for S, another element from the gas. These findings suggest that the surface of mature alum crust has a high adsorption capacity for those gaseous metals able to compensate for the lack of rock-derived cations. Based on the composition of gases escaping from the fracture hosting the crust, it is estimated that the partition coefficients of Tl (3.3 × 107), V (1.1 × 107) and Te (0.6 × 107) between crust surface and gases are two to four orders of magnitude higher than for other volatile metals and metalloids. It follows that gases equilibrating with anhydrous alums lose between 77 and 95% of their initial Tl content, but less than 1% of Pb. Given the Tl emission rate of Lascar volcano (5 g/day), between 17 and 104 g of toxic Tl would deposit every day if all Lascar gases were to equilibrate with anhydrous alums. This study suggests that anhydrous alums significantly immobilize Tl, V and Te in the ground of quiescent volcanoes, reducing the atmospheric emissions of these three elements.

A New Degassing Model to Infer Magma Dynamics from Radioactive Disequilibria in Volcanic Plumes

Mount Etna volcano (Sicily, Italy) is the place where short-lived radioactive disequilibrium measurements in volcanic gases were initiated more than 40 years ago. Almost two decades after the last measurements in Mount Etna plume, we carried out in 2015 a new survey of 210Pb-210Bi-210Po radioactive disequilibria in gaseous emanations from the volcano. These new results [ ( 210 Po / 210 Pb ) = 42 and ( 210 Bi / 210 Pb ) = 7.5 ] are in fair agreement with those previously reported. Previously published degassing models fail to explain satisfactorily measured activity ratios. We present here a new degassing model, which accounts for 222Rn enrichment in volcanic gases and its subsequent decay into 210Pb within gas bubbles en route to the surface. Theoretical short-lived radioactive disequilibria in volcanic gases predicted by this new model differ from those produced by the former models and better match the values we measured in the plume during the 2015 campaign. A Monte Carlo-like simulation based on variable parameters characterising the degassing process (magma residence time in the degassing reservoir, gas transfer time, Rn-Pb-Bi-Po volatilities, magma volatile content) suggests that short-lived disequilibria in volcanic gases may be of use to infer both magma dynamics and degassing kinetics beneath Mount Etna, and in general at basaltic volcanoes. However, this simulation emphasizes the need for accurately determined input parameters in order to produce unambiguous results, allowing sharp characterisation of degassing processes.

Study of the environmental variability of gaseous emanations over a CO2 injection pilot—Application to the French Pyrenean foreland

Prior to the CO2 injection in the Rousse pilot operated by TOTAL Exploration Production France, baseline monitoring has been performed in near surface environments in order to characterize soil gas concentrations and soil gas fluxes behavior along with time. The baseline measurements were conducted in 2008 and 2009 on a quarterly basis. All investigations were performed under weather conditions representative of temperate climate yearly cycles. CO2 fluxes and CO2 soil concentrations followed an annual cycle with enhanced emissions during high season (summer) and lower emissions during low season (winter) corresponding with the annual cycle of biological activity in soil. The CO2 is predominantly of organic origin with atmospheric dilution during low season times with an absence of an upward gas flux as suggested by nearly constant helium concentrations in soils and depleted carbon-13 isotope ratios. Even considering quite long baseline monitoring, it is not possible to find a significant correlation between the flux measured at the soil/atmosphere interface and the concentration measurements at 1m depth.From the knowledge gained at the site, a monitoring strategy is proposed in order to match both scientific and operator requirements.

Comparison of modelled uptake to cereal crops of 14C from gaseous or groundwater mediated pathways

AbstractCarbon-14 has been identified as one of the more significant radionuclides in solid radioactive wastes in a repository, due to the potential radiological impact arising if 14C were to be released and enter the biosphere. However, the assessment of radiation doses is complicated by the major role of carbon in biological processes, and this has tended to lead to the adoption of a cautious assessment approach.An international comparison of five models used to predict uptake of 14C to agricultural crops has been undertaken, within the BIOPROTA framework. Processes investigated include conversion of 14C-labelled CH4 into CO2 in soils, carbon accumulation in and release from soil carbon pools, gaseous emanation to, and dispersion from, the plant canopy atmosphere and, incorporation into plants by photosynthesis.For a unit rate of entry of 14C to soil, modelled activity concentrations in cereal crops differ by three to five orders of magnitude. This reflects, in part, differing assumptions for mixing and dispersion of air above the soil surface and within the crop canopy layer. For a unit activity concentration of 14C in air, the modelled uptake to cereal crops converges significantly. Following an assumed irrigation of crops with groundwater containing unit activity of 14C, the predicted uptake to crops varied by two to four orders of magnitude, again largely dominated by assumptions regarding the canopy atmosphere. In all cases, there is some convergence in model predictions as field size increases.A continuing programme of field research is being undertaken in parallel with the assessment work.

Fluoride content in drinking water supply in São Miguel volcanic island (Azores, Portugal)

High fluoride contents in the water supply of the city of Ponta Delgada, located in the volcanic island of São Miguel (Azores, Portugal) have been reported. Dental fluorosis in São Miguel has been identified and described in several medical surveys. The water supply in Ponta Delgada consists entirely of groundwater. A study was carried out in order to characterize the natural F-pollution of a group of springs (30) and wells (3), that are associated to active central volcanoes of a trachytic nature. Two springs known for their high content in fluoride were sampled, both located in the central volcano of Furnas.The sampled waters are cold, ranging from slightly acidic to slightly alkaline (pH range 6.53–7.60), exhibiting a low electrical conductivity (springs range 87–502μS/cm; wells range 237–1761μS/cm), and are mainly from the Na–HCO3, Na–HCO3–Cl and Na–Cl–HCO3 water types. Results suggest two main trends of geochemical evolution: silicate weathering, enhanced by CO2 dilution, and seawater spraying. Fluoride contents range between 0.17mg/L and 2mg/L, and no seasonal variations were detected. Results in the sources of the water supply system are lower than those of the Furnas volcano, which reach 5.09mgF/L, demonstrating the effect of F-rich gaseous emanations in this area. Instead, the higher fluoride contents in the water supply are mainly due to silicate weathering in aquifers made of more evolved volcanic rocks.

Low-Latitude Atmosphere-Ionosphere Effects Initiated by Strong Earthquakes Preparation Process

Ionospheric and atmospheric anomalies registered around the time of strong earthquakes in low-latitude regions are reported now regularly. Majority of these reports have the character of case studies without clear physical mechanism proposed. Here we try to present the general conception of low-latitude effects using the results of the recent author’s publications, including also rethinking the earlier results interpreted basing on recently established background physical mechanisms of anomalies generation. It should be underlined that only processes initiated by earthquake preparation are considered. Segregation of low-latitude regions for special consideration is connected with the important role of ionospheric equatorial anomaly in the seismoionospheric coupling and specific character of low-latitude earthquake initiated effects. Three main specific features can be marked in low-latitude ionospheric anomalies manifestation: the presence of magnetic conjugacy in majority of cases, local longitudinal asymmetry of effects observed in ionosphere in relation to the vertical projection of epicenter onto ionosphere, and equatorial anomaly reaction even on earthquakes outside equatorial anomaly (i.e., 30–40 LAT). The equality of effects morphology regardless they observed over land or over sea implies only one possible explanation that these anomalies are initiated by gaseous emanations from the Earth crust, and radon plays the major role.

Characterization by factor analysis of the chemical facies of groundwater in the deltaic plain sands aquifer of Warri, western Niger delta, Nigeria

This paper examines the hydrochemical facies of groundwater present in the Deltaic Plain Sands aquifer of Warri and its immediate environs, maps their areal distribution and attempts to explain the controlling processes responsible for the various facies. 60 water samples werecollected from wells tapping the Deltaic Plain Sands aquifer of Warri and environs and analyzed for various parameters including pH, total dissolved solids (TDS), K, Na, Ca, Mg, Cl, HCO3 and SO4 after standard procedures. The data obtained were subjected to R-mode factor analysis. Three factors were extracted. Factor 1 includes K, Na, Cl, and EC and reflects the signature of saline water incursion resulting from seepages into the aquifer of water from the tide-influenced RiverWarri. Factor 2 has high loading values of Mg, Ca, HCO3 and pH and represents the processes of natural rainwater recharge and water-soil/rock interaction. Factor 3 includes SO4 and can be related to the dissolution of sulphides from interstratified peat within the geological formation, heavy vehicular activity and the petroleum refining process in the town. The areal distributions of the various factor scores indicate that factors 1 and 2 are enhanced close to the banks of RiverWarri and decreases away from them. A broad zone of groundwater interaction (mixing) between water species represented by factors 1 and 2 is thus created towards the riverbanks. The implicationof this is that ionic concentration in the water decreases away from the banks of the river an indication that the quality of groundwater improves away from the river. Factor 3 is enhanced in the southeastern portion of the town where it is deemed to be caused by the dissolution bygroundwater of sulphur bearing minerals within the geological formaton, and also in the central and northwestern portions of the town were it could be related to the rain-dissolution of sulphur bearing compounds from gaseous emanations arising from vehicles and the petroleum refining process respectively, which eventually as acid-rain recharges aquifers in the vicinity. This paper demonstrates the effectiveness of factor analysis in evaluating hydrochemical processes in coastaland industrial areas

Contribution of public Geological Survey to prevention and mitigation of geohazards

From the early history of civilisation societies have been exposed to external factors. Probably no other factors have influenced the development of societies and cultures more than geologically driven hazards or geohazards. With the evolvement of societies also the approaches to solving problems, related to geohazard, have developed. The complexity of mitigation and response measurements that tackle the contemporary geohazard problems demands a long-term strategic approach that has to incorporate all segments of the society, from stake-holders and end-user groups to the experts. The management of geohazards is a public good and as such needs to be governed by a non-profit public body. The common mission of almost all geological surveys is to gather, manage and interpret geologically related data for a wider public welfare. Geological surveys as public institutions represent a key role in almost all components of the geohazard management process, from education and research, to data acquisition, processing, interpretation and decision support issues. With its knowledge regarding natural processes gathered through decades GSO offers reliable and independent support in assessing and describing the phenomena (seismic activities, mass wasting, water and soil pollution, excess or lack of trace elements in the soil, ground subsidence or heave, gaseous emanations and more), understanding the processes of activation, dynamics, transport, interaction with media and living organisms, and predicting the possible scenarios in the future with emphasis on human exposure to given phenomena. Despite the fact that the value of the knowledge of the dynamic environment we live in is being tested literally on daily basis in Slovenia, its inclusion in everyday practice is still relatively negligible.

Fluids and Stress in Fractured Rocks: A Case Study with Applications to Hydrodynamic Modelling (Lodeve basin, South France): ABSTRACT

In order to stock nuclear waste safely in fractured rock or optimize the development and exploitation of hydrocarbons in fractured reservoirs the same fracture parameters have to be investigated through field studies. It is essential to define the relationships between tectonics, 3D fracture networks and fluid flow, as well as the effect of past stress states on the network evolution and the effect of the present-day stress state on hydrodynamics. A case study was carried out on a site of the COGEMA Uranium mine with a very high density of wells and galleries in a Permian silicoclastic basin. Fracturation on all scales from individual fractures (with their connectivity and hydraulic behaviour) to fracture network was described. A multidisciplinary approach was necessary to understand the importance of fluids and to upscale metric scale obsessations to the well identified fracture network: 3D organization and evolution of the fracture network under the influence of paleostress was obtained from tectonic analysis and response of the reservoir in terms of fracture dilatancy or closure to present day stress was characterized by in situ stress measurements; water geochemistry and hydrogeology showed the large scale flow pattern characterized by the presence of main drains and barriers; geophysicalmore » prospecting and study of gaseous emanations from the soil helped to localize the subsurface fracture pattern, especially dilatant fractures. All this data is used to build a 3D model of the fracture pattern and its flow networks.« less

Nettoyage et degagement des agrafes au Musee National de Ceramique a Sevres

Abstract Research on the removal of iron staples from ceramics has led to a method now regularly used: a slight polarization followed by a gaseous emanation on the surface of the staple enables it to be freed from its corrosion products and from any filling material. The treated area is limited to the immediate vicinity of the staple. The absence of mechanical methods reduces the risks of flaking, cracking, scratches and breakage. The staple is conserved and stabilized.

A geochemical model for the abnormal fluoride concentrations in waters in parts of northern Tanzania

Natural waters in parts of northern Tanzania are characterized by exceptionally high fluoride contents in some rivers (12–26 mg/l), springs (15–63 mg/l) and alkaline ponds and lakes (60–690 mg/l). In lowland rivers most of the fluorides are derived from weathering of F-rich nephelinitic and carbonatitic rocks and soil whereas, in the rivers draining Mt. Meru crater, gaseous emanations through mineral springs may also contribute to the concentrations. The flushing of F-rich sodium bicarbonate (“magadi”) from the surface and top soil at the onset of the rainy season affects the F concentrations in shallow ground water and in surface water bodies. The steady flux of fluorides in ground water and overland flow and interflow containing dissolved “magadi” into internal alkaline ponds and lakes increases F (as well as CI) contents as a result of continuous evaporative enrichment over a long period. Very low Ca and Mg contents render the abnormally high F contents possible.The excessive F concentrations in drinking water cause endemic dental and skeletal fluorosis in people and in animals. The fluorous “magadi” used as an additive in food preparation is also considered to be a source of deleterious amounts of fluorides. The geomedical aspects of fluorine are discussed in the light of findings in the literature.

Etude de la formation de particules a partir des hydrocarbures naturels degages par la vegetation

The pine forest is a source of natural particles. The intensity of this source is calculated from measurements at ground level of concentrations of Aitken nuclei and of radon, a naturally radioactive gas which was used as a tracer of the variations of the vertical stability of the lower layers of the atmosphere. The concentrations of the Aitken nuclei exhibit a diurnal cycle linked to the solar intensity. The formation of this particulate matter results from the oxidation reactions of the gaseous emanations from the biomass with OH radicals and ozone, the rates of these different reactions vary with time over a period of 24 hr.

Gas output measurements from an active volcano

Remote sensing of volatile flows from active volcanoes together with direct measurements of concentration ratios of chemical species in volcanic plumes are highly valuable both for applied volcanology forecasts of eruptions and a better knowledge of fundamental geochemical and biochemical cycles. A method was devised on Mt Etna (CARBONNELLE et al., 1978) in order to evaluate the volcano emissions of a number of chemical species, viz. water vapor, carbon dioxide, sulfur dioxide, hydrochloric acid and hydrofluoric acid. Table 1 displays the results for those compounds which are also regarded as atmospheric pollutants. They show that the commonly admitted values concerning the contribution of volcanic eruptions to the atmosphere and hydrosphere appear to be largely underestimated when is also taken into account the worldwide mild volcanic activity. The June 1980 measurements on Mt. Etna aroused suspicions about the previous CO2 flux estimation when the carbon dioxide baseline in the ambient air on the slopes of the volcano was found to be persistently much over the normal atmospheric background (335_ 1 ppm). That the gaseous emanation of deep volcanic soils could be more important than the discharge of volcanic vents had been demonstrated for radon-222 (WILk~NING, 1974) on Hawaii and foreshadowed by SULERZHITZKY (1971) for CO 2. This latter author, trying to establish regulari-

Rapid Screening of ‘Satsuma’ Mandarin Progeny to Distinguish Nucellar and Zygotic Seedlings1

Abstract Nucellar and zygotic offspring of ‘Satsuma’ mandarin (Citrus reticulata Blanco) were differentiated by gas chromatographic analysis of gaseous emanations from fragmented leaves of 6-month-old seedlings. Analysis was rapid (< 3 minutes/sample), could be performed on individual leaves, and required virtually no tissue processing. Thus, the method is amenable to the screening of large progeny at the young seedling stage.

Regional Sources of Volcanic Carbon Dioxide and Their Influence on 14C Content of Present-Day Plant Material

14C measurements were made on present-day plant material with short integration times (tree leaves and sprouts) in the Eifel area, western Germany, where ancient volcanism produces gaseous emanations of considerable yield. Plants growing near sources emanating 14C-free CO2 show a significant depletion in the period of their growth. The same effect is found in the 14C content of recent samples from the Thera (Santorini) Archipelago/Greece. This mixing of “dead” CO2 may lead to pseudo ages in archaeologic or geologic samples of up to 1600 years in samples from the vicinity of CO2 emanating sources.

A Possible Source of Error in 14C Dates: Volcanic Emanations (Examples from the Monte Amiata District, Provinces of Grosseto and Sienna, Italy)

Wood from regular timbering of a shallow seated mine in Tuscany gave 14C ages of 5730 ± 100 years BP, much too old to be attributed to one of the known civilizations of Italy. This mine is located in a region of declining volcanic activity, noticeable especially through numerous emanations (natural or incidentally induced by drillings). It was suspected that the analyzed wood had grown in an environment where the normal atmosphere had been diluted by volcanic emanations. To check this hypothesis, living plants (trees, bushes and reeds) and volcanic emanations have been sampled and their 14C content measured. All present day plants are depleted in 14C, giving a fictitious age different from 0 (1805, 1820, 2540, 4350 years BP). Of the gaseous emanations sampled, two have a high pressure and show virtually no 14C (>41,000 years BP). Two others have a pressure close to atmospheric, and small amounts of 14C were introduced by atmospheric contamination (22,570 and 30,580 years BP).Conclusion: plants grown in the vicinity of volcanic emanations have 14C activities that are too low because of a natural 14C dilution and yield anomalously high ages. The δ13C values obtained for two of these plants (—27.4‰ and —23.7‰) are close to the average for plants in general (—25‰), whereas the CO2 of mofettes is heavier than atmospheric CO2.

Coastal submarine hydrothermal activity off northern Baja California

In situ observations of submarine hydrothermal activity have been conducted in Punta Banda, Baja California, Mexico, approximately 400 m from the coast and at a seawater depth of 30 m. The hydrothermal activity occurs within the Agua Bianca Fault, a major transverse structure of Northern Baja California. Hot springwater samples have been collected and analyzed. Marked differences exist between the submarine hot springwater, local land hot springwaters, groundwater, and local seawater. SiO2, HCO3−, Ca, K, Li, B, Ba, Rb, Fe, Mn, As, and Zn are enriched in the submarine hot springwater, while Cl, Na, SO42−, Mg, Cu, Ni, Cd, Cr, and perhaps Pb are depleted in relation to average and local seawater values. Very high temperatures, at the hydrothermal vents, have been recorded (102°C at 4‐atm pressure). Visible gaseous emanations rich in CH4 and N2 coexist with the hydrothermal solutions. Metalliferous deposits, pyrite, have been encountered with high concentrations of Fe, S, Si, Al, Mn, Ca, and the volatile elements As, Hg, Sb, and Tl. X ray dispersive spectrometry (1500‐ppm detection limit), X ray diffraction, and scanning electron microscopy of the isolated metalliferous precipitates indicate that the principal products of precipitation are pyrite and gypsum accompanied by minor amounts of amorphous material containing Si and Al. Chemical analyses and XRD of the reference control rocks of the locality (volcanics) versus the hydrothermally altered rocks indicate that high‐temperature and high‐pressure water‐rock interactions can in part explain the water chemistry characteristics of the submarine hydrothermal waters. Tritium dating of the hydrothermal solutions places them in the prebomb period of 1953 with an undetermined old age. Their long residence time, the occurrence of an extensive marine sedimentary formation, their association with CH4, and their similarities with connate waters of oil and gas fields suggest that another component of their genesis could be in cation exchange reactions within deeply buried sediments of marine origin. The approximate volume discharge of the hydrothermal system has been measured (330,000 m3/yr), and the overall convective heat flux over the mapped submarine hydrothermal area has been calculated, the value of which exceeds 105 times the reported average conductive flux through the sea floor. Our data and observations indicate that metal‐rich marine sediments and marine ore‐forming processes are a concurrent reality and that ores are being formed today in submarine areas of high convective heat flow where hydrothermal activity is the precursor for their occurrence. At the same time the results of our investigations have demonstrated that submarine hydrothermal activity and submarine hot springs exist in the ocean in regions characterized by relative quiescence and that technically ‘active’ ridge environments are not an exclusive prerequisite for their existence.

The nodulation and nitrogen fixation of isolated roots ofPhaseolus vulgaris L.

At a concentration of 3%, carbon dioxide completely inhibits nodulation. Ethylene at concentrations of 0.4 ppm and above is extremely inhibitory towards nodulation. The gaseous emanations from isolated root cultures, when permitted to accumulate, completely prevent nodulation and also inhibit the nitrogen fixation of existing nodules. Evidence is presented which suggests that ethylene is the active principle of the gaseous emanations.

Green Lemon Mold, Gaseous Emanation Products

Green Lemon Mold, Gaseous Emanation Products

Defoliation of Tomato Plant as a Response to Gaseous Emanations from the Fruit

Previous articleNext article No AccessDefoliation of Tomato Plant as a Response to Gaseous Emanations from the FruitJohn SkokJohn Skok Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 104, Number 3Mar., 1943 Article DOIhttps://doi.org/10.1086/335160 Views: 2Total views on this site Citations: 2Citations are reported from Crossref Journal History This article was published in the Botanical Gazette (1876-1991), which is continued by International Journal of Plant Sciences (1992-present). PDF download Crossref reports the following articles citing this article:E. R. Leonard Inter-Relations of vegetative and reproductive growth, with special reference to indeterminate plants, The Botanical Review 28, no.33 (Jul 1962): 353–410.https://doi.org/10.1007/BF02868688Allan G. Gawadi, George S. Avery LEAF ABSCISSION AND THE SO-CALLED “ABSCISSION LAYER”, American Journal of Botany 37, no.22 (Feb 1950): 172–180.https://doi.org/10.1002/j.1537-2197.1950.tb08174.x