Deception Island is a volcanic island located at the South Shetland Island off the Antartic Penin... more Deception Island is a volcanic island located at the South Shetland Island off the Antartic Peninsula. It constitutes a back-arc stratovolcano with a basal diameter of ~ 30 Km, the volcano rises ~ 1400 m from the seafloor to the maximum height, Mt. Pond of 540 m above sea level and over half the island is covered by glaciers. This island has a horse-shoe shape with a large flooded caldera with a diameter of about 6x10 km and a maximum depth of 190 m. This caldera is open to the sea through a narrow channel of 500 m at Neptunes Bellows. Deception Island shows the most recent active volcanism, evidence of several eruptions since the late 18th century, and well-known eruptions in 1967, 1969 and 1970 caused serious damage to local scientific stations. The aim of this study is to estimate the CO2 emissions from the Deception volcano bay. In-situ measurements of CO2 efflux from the surface environment of Deception Bay were performed by means of a portable Non Dispersive Infrared spectroph...
Precursory changes in the radon concentration of groundwater were observed prior to the Izu-Oshim... more Precursory changes in the radon concentration of groundwater were observed prior to the Izu-Oshima-kinkai earthquake (magnitude 7.0) 14 January 1978. The distance from the epicenter to a continuous radon-monitoring station at Nakaizu was about 25 kilometers. A sudden drop and a subsequent increase in the radon concentration recorded on 9 January 1978 were significant. The size of the spike-like change was about 15 percent. After the earthquake, a remarkable increase in the radon concentration occurred.
Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumen... more Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements shows that no fragment or sawdust of rock 12013 that has been analyzed to date is chemically similar to tektite glass. Rock sawdust is representative of "whole rock" composition only if the amount of contamination from the sawing process is known. After appropriate correction for saw wire contamination, analyses of sawdust yield fairly accurate averaged elemental compositions of complex clastic lunar and other rocks.
The helium-3/helium-4 ratio in bubbling gases from ten hot springs located around Mount Ontake, a... more The helium-3/helium-4 ratio in bubbling gases from ten hot springs located around Mount Ontake, an active volcano in central Japan, ranges from 1.71 to 6.15 times the atmospheric ratio. The value of the ratio decreases with distance from the central cone of the volcano. Such a tendency may be a characteristic of helium-3 emission in volcanic areas and suggests more
Abundances of 30 elements in seven lunar rocks and soil were determined by instrumental and radio... more Abundances of 30 elements in seven lunar rocks and soil were determined by instrumental and radiochemical activation analysis. Seven major and minor elements in chips from 27 rocks were determined by instrumental activation analysis. Abundances of ten bulk elements overlap for the breccia rocks and soil samples. All lunar rare earth elements distribution patterns resemble those found in terrestrial abyssal subalkaline basalt, but with Eu depleted by about 60 percent in all lunar samples compared to the adjacent rare earth elements. Precipitation of plagioclase and hypersthene achondritic-like minerals from a melt could account for Eu depletion and the observed distribution of rare earth elements. Abundances of Ti, Al, Ca, Na, and Mn determined by instrumental activation analysis in five core-tube soil samples indicate uniformity for Al and Mn and apparent differences (10 to 20 percent) for Ti, Ca, and Na at 7.8 and 10.5 centimeters as compared to 0to5.2 centimeter depths.
Journal of Volcanology and Geothermal Research, 2000
... These characteristics support the hypothesis that the groundwater chemistry of the Cañadas aq... more ... These characteristics support the hypothesis that the groundwater chemistry of the Cañadas aquifer is controlled by the input of deep-seated gases (especially CO 2 ) from the Teide volcanichydrothermal system ([Valentin et al., 1990] and [Navarro, 1996]). ...
Journal of Radioanalytical and Nuclear Chemistry Letters, 1991
Cesium content in eleven positions of a continental basalt with a columnar joint was determined b... more Cesium content in eleven positions of a continental basalt with a columnar joint was determined by means of neutron activation analysis. Concentration of cesium is about four times higher at the altered portions of the fracture than at the unaltered. Water and Fe3+ content determined by gravimetry, Mössbauer spectroscopy, and inductively coupled plasma optical emission spectroscopy were also correlated with cesium concentration, suggesting accumulation of cesium with ferric components. Such processes may be important for estimating the behavior of radiocesium in the environment.
ABSTRACT Airborne observations of atmospheric methane (CH4) mixing ratio were carried out over Si... more ABSTRACT Airborne observations of atmospheric methane (CH4) mixing ratio were carried out over Siberia during July 15-30, 1993, using a continuous measurement system. The distribution of CH4 in the upper troposphere at an altitude of about 7 km was highly variable (1.72-1.91 parts per million, or ppm), being affected by intrusion of stratospheric air, long-range transport of CH4 from the source region, and a synoptic-scale mixing process. During flights along nearly constant latitude between Yakutsk (62.10°N, 129.50°E) and Nizhnevartovsk (60.57°N, 76.40°E) on July 19 and 28 we observed large-scale enhancements of CH4 from near 90° to 100°E with a horizontal scale of more than 500 km. Accompanied by high humidity and low mixing ratios of CO2 and O3, the air masses with enhanced CH4 mixing ratio were considered to be affected by lower tropospheric air. The probable source region of the CH4 was inferred to be the West Siberian Lowland, which contains vast wetlands and huge oil/gas fields. The distribution of CH4 in the lower troposphere (0.1-3 km) over the boreal wetlands in the West Siberian Lowland, ranging from 1.85 ppm to 2.75 ppm, showed large accumulations near the ground in the morning. The short-term temporal variations in the vertical profile of CH4 mixing ratio revealed that the accumulated CH4 was transported to the free troposphere with the growth of the mixed layer. On the other hand, the distribution of CH4 (0.1-1 km) over the tundra areas in the Siberian Arctic was less variable (1.81-1.84 ppm), and little accumulation was observed.
Deception Island is a volcanic island located at the South Shetland Island off the Antartic Penin... more Deception Island is a volcanic island located at the South Shetland Island off the Antartic Peninsula. It constitutes a back-arc stratovolcano with a basal diameter of ~ 30 Km, the volcano rises ~ 1400 m from the seafloor to the maximum height, Mt. Pond of 540 m above sea level and over half the island is covered by glaciers. This island has a horse-shoe shape with a large flooded caldera with a diameter of about 6x10 km and a maximum depth of 190 m. This caldera is open to the sea through a narrow channel of 500 m at Neptunes Bellows. Deception Island shows the most recent active volcanism, evidence of several eruptions since the late 18th century, and well-known eruptions in 1967, 1969 and 1970 caused serious damage to local scientific stations. The aim of this study is to estimate the CO2 emissions from the Deception volcano bay. In-situ measurements of CO2 efflux from the surface environment of Deception Bay were performed by means of a portable Non Dispersive Infrared spectroph...
Precursory changes in the radon concentration of groundwater were observed prior to the Izu-Oshim... more Precursory changes in the radon concentration of groundwater were observed prior to the Izu-Oshima-kinkai earthquake (magnitude 7.0) 14 January 1978. The distance from the epicenter to a continuous radon-monitoring station at Nakaizu was about 25 kilometers. A sudden drop and a subsequent increase in the radon concentration recorded on 9 January 1978 were significant. The size of the spike-like change was about 15 percent. After the earthquake, a remarkable increase in the radon concentration occurred.
Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumen... more Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements shows that no fragment or sawdust of rock 12013 that has been analyzed to date is chemically similar to tektite glass. Rock sawdust is representative of "whole rock" composition only if the amount of contamination from the sawing process is known. After appropriate correction for saw wire contamination, analyses of sawdust yield fairly accurate averaged elemental compositions of complex clastic lunar and other rocks.
The helium-3/helium-4 ratio in bubbling gases from ten hot springs located around Mount Ontake, a... more The helium-3/helium-4 ratio in bubbling gases from ten hot springs located around Mount Ontake, an active volcano in central Japan, ranges from 1.71 to 6.15 times the atmospheric ratio. The value of the ratio decreases with distance from the central cone of the volcano. Such a tendency may be a characteristic of helium-3 emission in volcanic areas and suggests more
Abundances of 30 elements in seven lunar rocks and soil were determined by instrumental and radio... more Abundances of 30 elements in seven lunar rocks and soil were determined by instrumental and radiochemical activation analysis. Seven major and minor elements in chips from 27 rocks were determined by instrumental activation analysis. Abundances of ten bulk elements overlap for the breccia rocks and soil samples. All lunar rare earth elements distribution patterns resemble those found in terrestrial abyssal subalkaline basalt, but with Eu depleted by about 60 percent in all lunar samples compared to the adjacent rare earth elements. Precipitation of plagioclase and hypersthene achondritic-like minerals from a melt could account for Eu depletion and the observed distribution of rare earth elements. Abundances of Ti, Al, Ca, Na, and Mn determined by instrumental activation analysis in five core-tube soil samples indicate uniformity for Al and Mn and apparent differences (10 to 20 percent) for Ti, Ca, and Na at 7.8 and 10.5 centimeters as compared to 0to5.2 centimeter depths.
Journal of Volcanology and Geothermal Research, 2000
... These characteristics support the hypothesis that the groundwater chemistry of the Cañadas aq... more ... These characteristics support the hypothesis that the groundwater chemistry of the Cañadas aquifer is controlled by the input of deep-seated gases (especially CO 2 ) from the Teide volcanichydrothermal system ([Valentin et al., 1990] and [Navarro, 1996]). ...
Journal of Radioanalytical and Nuclear Chemistry Letters, 1991
Cesium content in eleven positions of a continental basalt with a columnar joint was determined b... more Cesium content in eleven positions of a continental basalt with a columnar joint was determined by means of neutron activation analysis. Concentration of cesium is about four times higher at the altered portions of the fracture than at the unaltered. Water and Fe3+ content determined by gravimetry, Mössbauer spectroscopy, and inductively coupled plasma optical emission spectroscopy were also correlated with cesium concentration, suggesting accumulation of cesium with ferric components. Such processes may be important for estimating the behavior of radiocesium in the environment.
ABSTRACT Airborne observations of atmospheric methane (CH4) mixing ratio were carried out over Si... more ABSTRACT Airborne observations of atmospheric methane (CH4) mixing ratio were carried out over Siberia during July 15-30, 1993, using a continuous measurement system. The distribution of CH4 in the upper troposphere at an altitude of about 7 km was highly variable (1.72-1.91 parts per million, or ppm), being affected by intrusion of stratospheric air, long-range transport of CH4 from the source region, and a synoptic-scale mixing process. During flights along nearly constant latitude between Yakutsk (62.10°N, 129.50°E) and Nizhnevartovsk (60.57°N, 76.40°E) on July 19 and 28 we observed large-scale enhancements of CH4 from near 90° to 100°E with a horizontal scale of more than 500 km. Accompanied by high humidity and low mixing ratios of CO2 and O3, the air masses with enhanced CH4 mixing ratio were considered to be affected by lower tropospheric air. The probable source region of the CH4 was inferred to be the West Siberian Lowland, which contains vast wetlands and huge oil/gas fields. The distribution of CH4 in the lower troposphere (0.1-3 km) over the boreal wetlands in the West Siberian Lowland, ranging from 1.85 ppm to 2.75 ppm, showed large accumulations near the ground in the morning. The short-term temporal variations in the vertical profile of CH4 mixing ratio revealed that the accumulated CH4 was transported to the free troposphere with the growth of the mixed layer. On the other hand, the distribution of CH4 (0.1-1 km) over the tundra areas in the Siberian Arctic was less variable (1.81-1.84 ppm), and little accumulation was observed.
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