Isotopic composition of helium, and CO2 and CH4 contents in gases produced along the New Zealand part of a convergent plate boundary

Giggenbach, Werner F.; Sano, Yuji; Wakita, Hiroshi

doi:10.1016/0016-7037(93)90549-c

Cited by 257 publications

(170 citation statements)

References 81 publications

Supporting

Mentioning

160

Contrasting

Unclassified

Order By: Relevance

“…Moreover, the 3 He/ 4 He ratio, which is very sensitive to the involvement of mantle melted material in crustal processes, does not show any evidence of primary mantle 3 He degassing in any of the three supposed rifting arms. On the contrary, although the values reported in Table 2 are a¡ected, somehow, by air taken during sampling (R/R a = 1 in the air), the majority of the samples show R/R a ratios similar to the average value for £uids generated in a very well developed old crust (R/R a = 0.02 in such a crust; [72]).…”

Section: Fluid Chemistry and Tectonicsmentioning

confidence: 91%

“…Gas samples have been collected with a plastic funnel and stored in two-way glass tubes for CO 2 , H 2 S, N 2 and 3 He/ 4 He isotopic ratio determinations and in pre-evacuated one-way glass tubes ¢lled with 50 ml 4 N NaOH solution [50] for the determination of inert low concentrated compounds. The bulk composition of gases has been determined with a Shimadzu 15A gas chromatograph equipped with a TCD detector and a Shimadzu 14A equipped with a FID detector.…”

Section: Sampling and Analytical Proceduresmentioning

confidence: 99%

“…Major (Na, K, Ca, Mg, HCO 3 , SO 4 and Cl) and minor (SiO 2 , B, Li, NH 4 , F, NO 3 and Br) components in solution (in mg/kg) are reported in Table 1 and the water classi¢cation has been made in Fig. 2 (Fig.…”

Section: Water Chemistrymentioning

confidence: 99%

“…We attribute these anomalous values to the improper sampling, since the gas was issued from a pool rich in putrid marshy material. The CH 4 and CO 2 may possibly be related to the in-situ alteration of algae and leaves in the pool. Light hydrocarbon contents (C 2^C5 in mg/kg in Table 2) are very low in the gas samples from the WC and the Cambay provinces while they are present in the SONATA province.…”

Section: Chemistry Of Gasesmentioning

confidence: 99%

“…The 3 He/ 4 He ratio in samples, reported as R/R a in Table 2 (where R is the measured 3 He/ 4 He in the sample and R a is the ratio in air = 1.4U10 36 ; [56]), ranges between 0.01 at Sativli (sample 1) and 0.26 at Sov (sample 24). Thus, most of the samples show a typical crustal ratio with the only exception being the Unapdeo sample (R/ R a = 0.53), the latter value being of secondary importance for the reasons mentioned above.…”

Section: Chemistry Of Gasesmentioning

confidence: 99%

See 4 more Smart Citations

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

Minissale¹,

Vaselli

Chandrasekharam

et al. 2000

Earth and Planetary Science Letters

View full text Add to dashboard Cite

Section: Fluid Chemistry and Tectonicsmentioning

confidence: 91%

Section: Sampling and Analytical Proceduresmentioning

confidence: 99%

Section: Water Chemistrymentioning

confidence: 99%

Section: Chemistry Of Gasesmentioning

confidence: 99%

Section: Chemistry Of Gasesmentioning

confidence: 99%

See 3 more Smart Citations

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

Minissale¹,

Vaselli

Chandrasekharam

et al. 2000

Earth and Planetary Science Letters

View full text Add to dashboard Cite

CO₂ discharge from the bottom of volcanic Lake Rotomahana, New Zealand

Mazot

Schwandner

Christenson

et al. 2014

Geochem Geophys Geosyst

View full text Add to dashboard Cite

, CO 2 flux surveys were performed on Lake Rotomahana, New Zealand. The area has been hydrothermally active with fumaroles and sublacustrine hydrothermal activity before and since the eruption of Mt Tarawera in 1886. The total CO 2 emission from the lake calculated by sequential Gaussian simulation is 549 6 72 t d 21 . Two different mechanisms of degassing, diffusion through the water-air interface and bubbling, are distinguished using a graphical statistical approach. The carbon dioxide budget calculated for the lake confirms that the main source of CO 2 to the atmosphere is by diffusion covering 94.5% of the lake area (mean CO 2 flux 25 g m 22 d 21 ) and to a lesser extent, bubbling (mean CO 2 flux 1297 g m 22 d 21 ). Mapping of the CO 2 flux over the entire lake, including over lake floor vents detected during the survey, correlates with eruption craters formed during the 1886 eruption. These surveys also follow regional tectonic patterns present in the southeastern sector of Lake Rotomahana suggesting a deep magmatic source ( 10 km) for CO 2 and different pathways for the gas to escape to the surface. The values of d 13 C CO2 (22.88 and 22.39&) confirm the magmatic origin of CO 2 .

show abstract

New mafic magma refilling a quiescent volcano: Evidence from He-Ne-Ar isotopes during the 2011-2012 unrest at Santorini, Greece

Rizzo

Barberi

Carapezza

et al. 2015

Geochem. Geophys. Geosyst.

View full text Add to dashboard Cite

In 2011-2012, Santorini was characterized by seismic-geodetic-geochemical unrest, which was unprecedented since the most-recent eruption occurred in 1950 and led to fear an eruption was imminent. This unrest offered a chance for investigating the processes leading to volcanic reactivation and the compositional characteristics of involved magma. We have thus analyzed the He-Ne-Ar-isotope composition of fluid inclusions in olivines and clinopyroxenes from cumulate mafic enclaves hosted in cogenetic dacitic lavas of the 1570-1573 and 1925-1928 eruptions of Nea Kameni. These unique data on Aegean volcanism were compared with those of gases collected in quiescent periods and during the unrest. The 3 He/ 4 He ratios (3.1-4.0 Ra) are significantly lower than the typical arc-volcano values (R/Ra $ 7-8), suggesting the occurrence of magma contamination in Santorini plumbing system, which would further modify the 3 He/ 4 He ratio of parental magmas generated in the local metasomatized mantle. The 3 He/ 4 He values of enclaves (3.1-3.6 Ra) are comparable to those measured in gases during quiescent periods, confirming that enclaves reflect the He-isotope signature of magma residing at shallow depths and feeding passive degassing. A significant increase in soil CO 2 flux from Nea Kameni and anomalous compositional variations in the fumaroles were identified during the unrest, accordingly with previous studies. Simultaneously, 3 He/ 4 He ratios up to 4.0 Ra were also measured, demonstrating that the unrest was due to the intrusion into the shallow plumbing system of a more-primitive 3 He-rich magma, which is even volatile richer and less contaminated than mafic magma erupted as enclaves. This new intrusion did not however trigger an eruption.

show abstract

Isotopic composition of helium, and CO2 and CH4 contents in gases produced along the New Zealand part of a convergent plate boundary

Cited by 257 publications

References 81 publications

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

CO₂ discharge from the bottom of volcanic Lake Rotomahana, New Zealand

New mafic magma refilling a quiescent volcano: Evidence from He-Ne-Ar isotopes during the 2011-2012 unrest at Santorini, Greece

Contact Info

Product

Resources

About

Isotopic composition of helium, and CO2 and CH4 contents in gases produced along the New Zealand part of a convergent plate boundary

Cited by 257 publications

References 81 publications

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

Origin and evolution of ‘intracratonic’ thermal fluids from central-western peninsular India

CO2 discharge from the bottom of volcanic Lake Rotomahana, New Zealand

New mafic magma refilling a quiescent volcano: Evidence from He-Ne-Ar isotopes during the 2011-2012 unrest at Santorini, Greece

Contact Info

Product

Resources

About

CO₂ discharge from the bottom of volcanic Lake Rotomahana, New Zealand