Showing papers in "Geochemical Journal in 1982"
61 citations
TL;DR: Fumarolic gas samples collected from the hottest fumarole of the Showashinzan volcano on 15 occasions during the period from 1954 to 1978 have been examined for chemical and isotopic compositions as mentioned in this paper.
Abstract: Fumarolic gas samples collected from the hottest fumarole of the Showashinzan volcano on 15 occasions during the period from 1954 to 1978 have been examined for chemical and isotopic compositions. The fumarolic gases considerably changed their composition and temperature with time, owing probably to exhaustion of primary volcanic gases and mixing with water vapor originated from local surface waters soaking into the volcano. It has been also shown that the atmospheric contamination, lowering of temperature and reactions with the surrounding materials were important additional factors involved in the alteration of fumarolic gases. The change in gas composition with time may be considered to be indicative of the history of a volcanic hydrothermal system formed by intrusion of dacite magma.
59 citations
TL;DR: In this paper, a magnetic deflection mass spectrometer equipped with a metallic high-vacuum purification line was used to measure the 3He/4He and 20Ne/ 4He ratios in 12 CH4-rich natural gas samples.
Abstract: Measurements of 3He/4He and 20Ne/4He ratios in 12 CH4-rich natural gas samples were made with a magnetic deflection mass spectrometer equipped with a metallic high-vacuum purification line. In order to check the resolving power, sensitivity and stability of the mass spectrometer, atmospheric air in Tokyo was measured repeatedly. The mean 3He/4He ratio in Tokyo air was (1.43 ± 0.03) × 10-6. CH4-rich gases with significantly high 3He/4He ratios were first observed in this study. The 3He/4He ratios for 5 natural gas samples collected from hot springs and mineral springs in inland basins were as high as (1.7–7.3) × 10-6, probably due to the large contribution of the upper mantle-derived He. In comparison, the 3He/4He ratios for 2 samples from water wells distributed in coastal areas facing the Pacific Ocean and 5 samples from gas fields in the southern Kanto district were as low as ∼10-7. Most of the He in these gases is inferred to be radiogenic and of crustal origin.
53 citations
TL;DR: In this article, the decomposition of calcium carbonate and organic carbon in deep ocean water is subject to inaccuracies due to the effect of phosphate released from decomposition on titration alkalinity not being properly evaluated.
Abstract: Previous estimates of the decomposition of calcium carbonate and organic carbon in deep ocean water are subject to inaccuracies due to (1) the effect of phosphate released from the decomposition of organic matter on titration alkalinity not being properly evaluated, (2) the variation of the preformed properties not being considered, and (3) the input of anthropogenic CO2 not being corrected for. More accurate results are presented here for selected stations in the South Pacific.
43 citations
TL;DR: The results of analyses on water-soluble components in volcanic ashes, gases absorbed into alkaline solutions, and gases diffused into the atmosphere revealed that HCl/SO2 ratio increased prior to any surface activity such as frequency of explosions as mentioned in this paper.
Abstract: Concentrations of chlorine and sulfur bearing species in volcanic gases from the Sakurajima Volcano have been continuously measured by a variety of collection techniques and analytical methods. The results of analyses on water-soluble components in volcanic ashes, gases absorbed into alkaline solutions, and gases diffused into the atmosphere revealed that HCl/SO2 ratio increased prior to any surface activity such as frequency of explosions. It is suggested that HCl/SO2 ratio can be one of the useful precursory indicators for volcanic activity.
41 citations
34 citations
TL;DR: Partition coefficients of rare-earth elements (REE), Ba and Sr were precisely determined for crystal glass pairs prepared by partial melting and partial solidification of alkali olivine basalt at 10 and 20kb as mentioned in this paper.
Abstract: Partition coefficients of rare-earth elements (REE), Ba and Sr were precisely determined for crystal glass pairs prepared by partial melting and partial solidification of alkali olivine basalt at 10kb and of picrite basalt at 10 and 20kb. Mutually unfractionated REE partition patterns were observed for olivine-glass pairs prepared by partial melting and partial solidification experiments on alkali olivine basalt. A similar unfractionated REE pattern was observed for (clinopyroxene + olivine)/glass formed by 10kb partial melting of picrite basalt. On the other hand, clinopyroxene was produced in 10kb partial solidification of the same picrite basalt and the clinopyroxene showed fractionated, terrace-shaped REE partition pattern. Partial solidification experiments on picrite basalt produced only clinopyroxene as a mineral coexisting with melt, and the resultant REE partition pattern was a guyot-shaped one. It should be noted that the REE partition pattern (terrace-shaped or guyot-shaped) of clinopyroxene bears on the mutual relationship concerning the relative magnitudes of partition values of Fe and heavy REE. Finally, it is worth while to note that clinopyroxene is prevailingly formed in partial solidification process.
33 citations
TL;DR: In this paper, anhydrite samples from the submarine hydrothermal sulphide/sulphate mineral deposits found along the crest of the East Pacific Rise at 21 °N have been examined for filling temperature of fluid inclusions and for 34S/32S and 18O/16O ratios.
Abstract: Six anhydrite samples from the submarine hydrothermal sulphide/sulphate mineral deposits found along the crest of the East Pacific Rise at 21 °N have been examined for filling temperature of fluid inclusions and for 34S/32S and 18O/16O ratios. The anhydrite was precipitated upon mixing of hot (260–350°C), SO42--poor hydrothermal fluids with cold seawater at various proportions, which is reflected in a large variation in the filling temperatures ranging from 180°C to almost the highest exit temperatures. Seawater sulphate origin for anhydrite-sulphur is indicated by the δ34S values that are essentially identical with the present-day seawater sulphate value, whereas the δ18O values are up to 2‰ higher than the seawater sulphate value. The anhydrites are not in oxygen isotopic equilibrium with the mixed solution at measured exit temperatures of 260 to 350°C. However, this enrichment of 18O may be attributed to partial equilibration of fine-grained anhydrite with solutions at lower temperatures after deposition. Absence of anhydrite at dead vents suggests that SO42- slightly enriched in 18O is added to seawater sulphate owing to dissolution of anhydrite after the cessation of a high temperature stage of the hydrothermal activity.
31 citations
TL;DR: Isotopic age determinations were carried out for Jurassic siliceous shale (assigned to Bajocian by radiolarian fossils) and for Triassic bedded chert in Unuma, Gifu Prefecture, Central Japan as discussed by the authors.
Abstract: Isotopic age determinations were carried out for Jurassic siliceous shale (assigned to Bajocian by radiolarian fossils) and for, Triassic bedded chert (assigned to Anisian by radiolarians and conodonts) in Unuma, Gifu Prefecture, Central Japan. Whole-rock samples of the Jurassic shale give a Rb-Sr isochron age of 179.8 ± 5.7 Ma with an initial 87Sr/86Sr ratio of 0.71011 ± 0.00036, whereas two of these Jurassic samples have K-Ar whole-rock ages of 151 and 152 Ma. For the Triassic chert, the Rb-Sr whole-rock isochron shows 211.9 ± 4.7 Ma with an initial 87Sr/86Sr ratio of 0.71325 ± 0.00020, and a K-Ar whole-rock age for one of these Triassic samples is 207 ± 7 Ma. Two Rb-Sr whole-rock isochron ages indicate the time when the respective sedimentary rocks became chemically closed with regard to the Rb-Sr system. The initial 87Sr/86Sr ratios in both sets of rocks are higher than the contemporaneous marine 87Sr/86Sr ratio, suggesting the existence of an older landmass. The K-Ar ages of the Jurassic siliceous shale presumably represent the time of a later geologic event.
30 citations
TL;DR: In this paper, major and trace elements have been determined in spinel lherzolite, spinel pyroxenite and garnet websterite xenoliths from the Hoggar and in their host basanites and nephelinites.
Abstract: Major and trace elements have been determined in spinel lherzolite, spinel pyroxenite and garnet websterite xenoliths from the Hoggar and in their host basanites and nephelinites. Transition metal and REE abundances do not support a genetic link between these ultramafic rocks and the lavas erupted at the surface. Mineral chemistry and textures suggest a complex evolution and subsolidus re-equilibration in the range 800–1, 000°C. High-density CO2 fluid-inclusions define minimum pressures of 10–12kb. Thus the ultramafic xenoliths came from a relatively low pressure regime within an inhomogeneous lithospheric mantle segment characterized by a disturbed geotherm.
27 citations
TL;DR: In this paper, aqueous fluid and dissolved water (structural water) in the melt were measured and the fractionation factors between this and other waters from aqueus fluid were estimated, showing that deuterium is enriched in the dissolved water for albite and K-feldspar melts, D/H ratios of waters of 1), 3) and 4) were measured.
Abstract: Quartz, K-feldspar, albite and anorthite were equilibrated with water vapor in Pt capsules at 20kb and in the temperature range from 800 to 1, 300°C. The water in the capsules during the high temperature and pressure run seems to exist in two states, aqueous fluid and dissolved water (structural water) in the melt. In the process of extracting these waters, four kinds of water were distinguished experimentally: 1) Water extracted by puncturing the capsule in vacuum, 2) Water released from bubbles in quenched products, i.e., glasses, during grinding in an agate mortar, 3) Water extracted from pulverized product in evacuation process at room temperature, and 4) Water extracted in vacuum at high temperature. D/H ratios of waters of 1), 3) and 4) were measured. Taking water 4) to be dissolved water in melt, the fractionation factors between this and other waters from aqueous fluid were estimated. Deuterium is enriched in the dissolved water for albite and K-feldspar melts, D/H is almost the same for the aqueous fluid and dissolved water in the anorthite melt, and deuterium is much depleted in the dissolved water in the quartz melt.
TL;DR: In this article, the behaviour of rubidium, lithium, strontium and barium in superficial waters of a granitic area are compared with the behavior of the associated major element: potassium, magnesium, calcium and potassium.
Abstract: The behaviour of rubidium, lithium, strontium and barium in superficial waters of a granitic area are compared with the behaviour of the associated major element: potassium, magnesium, calcium and potassium. Fractionation during dissolution is important for the Rb/K couple, whereas fractionation during deposition of new-formed minerals or uptake by vegetation is important for Mg/Li and K/Ba. Auxiliary minerals seem to play an important part in the relative concentrations of strontium and calcium in the waters.
TL;DR: In this paper, the ordering of opal-CT is discussed in relation to the diagenetic process of siliceous sediments and the decreasing rate of d(101) spacing is approximately expressed by equation (4) given in the text, irrespective of chemical conditions and transformation sequence of silica.
Abstract: Hydrothermal experiments treating amorphous silica (opal-A) in an alkaline solution have disclosed. that opal-CT is formed from opal-A or silica-X and is transformed to quartz directly or through silica-K. During the transformation of silica, the d(101) spacing of cristobalite decreases continuously from d(101) = 4.11 A to 4.05 A, which suggests a progressive ordering of opal-CT. The decreasing rate of d(101) spacing is approximately expressed by equation (4) given in the text, irrespective of chemical conditions and the transformation sequence of silica. The rate constant is strongly dependent on the reaction temperature but more or less affected by the chemical condition and by the transformation sequence of silica. On the basis of the experimental results, the ordering of opal-CT is discussed in relation to the diagenetic process of siliceous sediments.
TL;DR: In this paper, it was shown that the high-pressure near-liquidus to near-solidus phases precipitated from basanitic magmas are compatible with derivation by small degrees of melting of an inhomogeneous mantle source recently enriched in LREE and other incompatible elements.
Abstract: Some xenolith-bearing Hoggar basanites and nephelinites possibly represent primary or near-primary magmas on account of their mg and Ni values. Simple model calculations show that they could be derived by 5–8 percent partial melting of a garnet-bearing pyrolite source. They are characterized by LREE enriched abundance patterns and by highly variable abundances of compatible and incompatible trace elements. These compositional features are compatible with derivation by small degrees of melting of an inhomogeneous mantle source recently enriched in LREE and other incompatible elements. Model calculations involving transition metal and REE contents do not support a cogenetic origin of the ultramafic xenoliths as source or residual material. Megacrysts of kaersutite, clinopyroxene, orthopyroxene, oligoclase, ilmenite and zircon are considered to represent high-pressure near-liquidus to near-solidus phases precipitated from basanitic magmas. Inconsistencies in trace element contents of some kaersutites and clinopyroxenes and host basalts suggest that these megacrysts are not strictly cognate with respect to their present hosts.
TL;DR: In this paper, the variations of 10Be flux, 9Be concentration and 10Be/9Be atomic ratio from core to core are discussed in the light of a scavenging process of the beryllium isotopes.
Abstract: The concentration profiles of 9Be, 10Be and 230Thexc have been measured in two oceanic sediment cores from near Antarctica in the Pacific The 10Be and 9Be depth profiles in eleven Pacific cores investigated so far by our group have been summarized, and the variations of 10Be flux, 9Be concentration and 10Be/9Be atomic ratio from core to core are discussed in the light of a scavenging process of the beryllium isotopes
TL;DR: In this article, stable isotopic composition and radiometric age were measured for groundwaters in the Emilia area of the Po sedimentary basin (Northern Italy) in order to confirm the presence of paleowaters in the sedimentary basins.
Abstract: Stable isotopic composition and radiometric age were measured for groundwaters in the Emilia area of the Po sedimentary basin (Northern Italy). Waters from unconfined shallower aquifers, deep circulating continental waters and sodium chloride waters (relic waters) squeezed out from underlying marine formations during past geological events were considered. Waters from supposed confined aquifers (paleowaters) are usually depleted in 0–18 (δ18O < -10‰) and their δ18O–δD relationships are not consistent with their belonging to the present hydrological cycle. Isotope data on sodium chloride waters suggest mixing of relic saline waters with deep circulating continental waters. Processes affecting stable isotope composition of groundwaters in unconsolidated sediments are discussed. Oxygen isotope chemistry is considered to be a rather conservative parameter at least at low temperatures, thus able to give paleoclimatic information. Some 14C age data on deep circulating groundwaters suggest permanence times within the aquifers greater than 15, 000yrs in some cases. These data agree with paleoclimatological deductions in pointing out the presence of paleowaters in the Po sedimentary basin.
TL;DR: An attempt was made to determine both elemental and isotopic abundances of rare gases in natural gases by means of a conventional quadrupole mass spectrometer (QMS) as discussed by the authors.
Abstract: An attempt was made to determine both elemental and isotopic abundances of rare gases in natural gases by means of a conventional quadrupole mass spectrometer (QMS). Elemental abundances and isotopic ratios of Ar, Kr and Xe on the atmospheric concentration level were successfully measured by the present method. Reproducibility of 10–20% was obtained for 4He, 20Ne, 36Ar, 84Kr and 132Xe measurements. Isotopic ratios of Ar, Kr and Xe were determined within about 2% experimental errors, except for 78Kr/84Kr, 124Xe/132Xe and 126Xe/132Xe. Sensitivity and reproducibility of the measurements were examined by repeating runs of the atmospheric air. In order to verify the applicability of the present method to terrestrial natural gas analyses, eight typical samples of natural gases in Japan, with differences in major compositions, were measured. The values observed by a QMS in this work are generally in good agreement with those obtained by magnetic deflection mass spectrometers. Enrichment of radiogenic 40Ar was observed in some CO2-rich natural gas samples. Observed Kr and Xe isotopic ratios in N2-rich gases and CH4-rich gases coincided with the atmospheric ratios within experimental error.
TL;DR: In this paper, the Ca, Ba and Ca contents of basalts and andesites from Miyakejima, Onoharajima, Mikurajima and Inambajima volcanoes, the Izu Islands, Japan, have been determined by an inductively coupled plasma optical emission spectrometer.
Abstract: Ca, Sr and Ba contents of basalts and andesites from Miyakejima, Onoharajima, Mikurajima and Inambajima volcanoes, the Izu Islands, Japan, have been determined by an inductively coupled plasma optical emission spectrometer. The data reveal that Miyakejima, Onoharajima and Mikurajima volcanoes gave three different series of Sr/Ca-Ba/Ca systematics, while an Inambajima andesite belongs to Mikurajima systematics. The difference is considered to reflect different degrees of partial melting of a common mantle material with chondritic Sr/Ca and Ba/Ca ratios. The degree of partial melting decreases from Oshima to Miyakejima and is constant from Miyakejima to Mikurajima along the arc, while it decreases from Miyakejima to Onoharajima across the arc. Therefore, there seems to be no relationship between the “degree” of partial melting and the distance from the Izu-Ogasawara Trench in this region.
TL;DR: It is interpreted that the B fraction originated from the diatom cell walls, not from the amino acid associated with aluminosilicate such as clay in sediments.
Abstract: Total amino acids in marine sediments was determined by the combined use of hydrochloric acid hydrolysis (A fraction) and hydrofluoric acid treatment (B fraction). The B fraction comprised 5 to 10% of the total amino acids. The amino acid composition of B fraction indicated a characteristic feature that threonine and serine were relatively abundant. The amino acid composition of B fraction resembles that of diatom cell walls as pointed out by HECKEY et al. From this fact, it is interpreted that the B fraction originated from the diatom cell walls, not from the amino acid associated with aluminosilicate such as clay in sediments.
TL;DR: In this article, the authors used the ICP-OES method to determine the Ca, Ba and Ca contents in various volcanic rocks (basalts, andesites, rhyolites and their cognate inclusions) from Quaternary volcanoes in Toshima, Udonejima, Niijima and Kozushima, the Izu Islands, Japan, have been determined by an ICP OES method, indicating that there exist two different primary magmas derived from a common mantle peridotite with different degrees of partial melting.
Abstract: Ca, Sr and Ba contents in various volcanic rocks (basalts, andesites, rhyolites and their cognate inclusions) from Quaternary volcanoes in Toshima, Udonejima, Niijima and Kozushima, the Izu Islands, Japan, have been determined by an ICP-OES method. Basalts and andesites from Toshima and Niijima make two different series of Sr/Ca-Ba/Ca systematics (SB systematics), indicating that there exist two different primary magmas derived from a common mantle peridotite with different degrees of partial melting. The various series of SB systematics of volcanoes in the Izu Islands so far obtained, suggest that the common mantle peridotite has a chondritic composition in terms of Sr/Ca and Ba/Ca ratios. The various series of SB systematics defined by basalt-andesite-dacite series in the Izu Islands converge into a rhyolitic composition of Jinaijima type. The silicic rock may be an end product of a crystal fractionation process, and might have formed a thin crust under the Niijima and Kozushima region. The majority of rhyolites which characterize the volcanoes of Niijima and Kozushima display quite different SB systematics, suggesting that the rhyolites are formed by remelting of a thin crust, and substraction of Na-rich plagioclase from the silicic magma. The rhyolite volcanism may be triggered by the heat of basaltic magma intruded under the thin crust, as indicated by the presence of cognate inclusions with basaltic composition in the rhyolites.
TL;DR: In this paper, the applicability of Rayleigh distillation to rate processes was discussed, and it was shown that the equation can be applied ubiquitously in the case of first-order rate processes.
Abstract: The equation of Rayleigh distillation was interrelated with similar equations of other types. An emphasis was laid on the applicability of Rayleigh distillation to rate processes. In the case of first-order rate processes, the equation of Rayleigh distillation can be applied ubiquitously. In the cases of zeroth, second and higher order rate processes, the equation is only applicable under certain restrictions.
TL;DR: In this paper, the potential of vacuum pyrolysis to characterize the chemical nature of the humic materials is discussed, and the potential for the technique to characterise the chemical properties of humic material is discussed.
Abstract: Humic acid and kerogen samples isolated from some Recent sediments of different environments were analyzed by vacuum pyrolysis to characterize their chemical nature. The samples were pyrolysed at 500°C in vacuo (about 10-2 Torr.). Gravimetric and elemental analyses of the pyrolysis residue indicated that the pyrolytic degradation resulted in the loss of carbon and nitrogen in the range of 35–53% and 53–68%, respectively. The pyrolysate was trapped and extracted with chloroform. It was fractionated using silica gel and Ag+-impregnated silica gel column chromatography. Subsequent gas chromatographic analyses enabled quantification of n-alkane and n-alkene homologues. Generated straight-chain hydrocarbons (≥C14) amounted to about 1–4mg per g carbon in the humic acids and to about 2–20mg per g carbon in the kerogens. The potential of the technique to characterize the chemical nature of the humic materials is discussed.
TL;DR: Pelagic manganese nodules were sampled at two sites in the equatorial and subtropical regions of the world as discussed by the authors, and it was shown that the bottom surface is now growing with Th supplied chiefly from weathering debris rather than authigenic particles in sea water.
Abstract: Pelagic manganese nodules were sampled at two sites. One was in the subtropical Pacific where the biological productivity in the surface water was low and Mn did not migrate in the surface sediment. The other was in the equatorial Pacific where manganese oxide in the sediment was reduced by organic material and dissolved Mn was lost from the sediment to the bottom water. It has been demonstrated that the difference in the sedimentary environment is reflected in manganese nodules. The bottom surface of the equatorial nodules contained larger amounts of transition metals soluble in weak acids than other sides in contact with sea water and the acid soluble metals decreased with depth from the bottom surface. On the bottom side of the equatorial nodule the oxide fractions of Cu and Ni increased with depth, indicating the trapping of metals which diffused through the pore waters of sediments and nodules. The bottom surface of the larger subtropical noudles contained much smaller amounts of 230Th than other surfaces, but the growth rate obtained from the depth profile of 230Th was similar to those of the other surfaces. The smaller subtropical nodules contained a normal amount of 230Th at the bottom surface. The concentration of 232Th decreased with depth at each surface, that is, with time, except for the bottom surface of the larger subtropical nodules, in which 232Th concentration is similar to that in the interior of nodules. These observations apparently lead to the conclusion that the bottom surface of the larger subtropical nodules are not growing at present, but the following possibility can not be excluded. The bottom surface is now growing with Th supplied chiefly from weathering debris rather than authigenic particles in sea water.
TL;DR: In this paper, the ICP-OES method was used to determine the Ca, Ba and Ca contents of various volcanic rocks (basalts, andesites, dacites and a granitic xenolith) from the Higashi-Izu monogenetic volcano group, the Izu Peninsula, Japan, have been determined by an ICP.
Abstract: Ca, Sr and Ba contents of various volcanic rocks (basalts, andesites, dacites and a granitic xenolith) from the Higashi-Izu monogenetic volcano group, the Izu Peninsula, Japan, have been determined by an ICP-OES method. The results indicate that the monogenetic volcano group makes a Sr/Ca-Ba/Ca systematics which is similar to that defined by a stratovolcano. The SB systematics suggests that there are two different high alumina basalt magmas in the Higashi-Izu monogenetic volcano group: one (basalt I) is a primitive basalt magma derived from the mantle with rather small degree of partial melting and the other (basalt II) is a mixture of the primitive basalt magma and a cumulus phase enriched in plagioclase. The high alumina basalt series (basalt (I)-andesite-dacite series) is considered to be established, not by crystal fractionation process in magma chamber, but by assimilation process of the primary basalt magma with the granitic crust. The crust under the Izu Peninsula may have a chemical composition similar to that of the dacite(I) from Kawagodaira.
TL;DR: In this article, the isotopic composition of secondary and possibly primary carbonates has been investigated for 75 samples from Hole 418 A, a 550m long basalt sequence drilled during DSDP Legs 52 and 53 to the south of the Bermuda Rise, in the Atlantic Ocean.
Abstract: Oceanic basalts are often altered by circulating seawater. During this process carbonates are formed frequently as veinlets and crystal aggregates. Additionally hydrothermal carbonate is found occasionally. The isotopic composition of secondary and possibly primary carbonates has been investigated for 75 samples from Hole 418 A, a 550m long basalt sequence drilled during DSDP Legs 52 and 53 to the south of the Bermuda Rise, in the Atlantic Ocean. Isotope ratios of secondary carbonates, carbonate rich basalts and some of the so called “fresh” basalts have values typical for marine carbonates, i.e., δ13C +2.8 to -2.3‰ vs. PDB. Isotope ratios of samples with small carbonate content fall in the range of primary magmatic carbon, i.e., δ13C -4 to -8‰. The carbon isotope composition of carbonates in oceanic basalts is therefore constituted by an overprinting of seawater-derived secondary carbonates on traces of primary carbonate carbon.
TL;DR: The distribution of chemical elements in the Earth's crust and its inferred interior is controlled mainly by the density periodicity of the elements, and is further perturbed by chemical affinity as discussed by the authors.
Abstract: The distribution of chemical elements in the Earth's crust and its inferred interior is controlled mainly by the density periodicity of the elements, and is further perturbed by chemical affinity of the elements. The chemical elements have been classified into four major groups: heavy, medial, light and volatile, according to the physical and chemical properties and the distribution pattern of the elements. The light elements are generally enriched in the Earth's surface and the heavy elements are concentrated in its center. The abundances of most of the heavy and light elements increase and decrease respectively, very rapidly with increasing depth, whereas those for the medial and volatile elements remain relatively uniform throughout the Earth (except the core). Chemical affinity controls the abundances of the volatile and medial elements more than those of the light and heavy elements. On the basis of the principles of elemental distribution observed in the Earth, it is deduced that the chondrites were formed in an enviornment which experienced little gravitational influence, whereas the achondrites were formed under the influence of gravitation. The distribution of chemical elements in the Sun does not appear to be influenced by its gravitational field, which might be a consequence of nuclear fusion processes.
TL;DR: In this paper, five separate fractions of noble gases were extracted and analyzed as a 150g sample of the Canyon Diablo iron meteorite was heated to successively higher temperatures by direct coupling with an RF coil.
Abstract: Five separate fractions of noble gases were extracted and analyzed as a 150g sample of the Canyon Diablo iron meteorite was heated to successively higher temperatures by direct coupling with an RF coil. Isotopic compositions of the light gases, He, Ne and Ar, demonstrate that essentially their entire inventory was produced by spallation reactions. Spallation products are also a prominent feature of the isotopes of Kr and Xe, but in each gas fraction the spallogenic heavy gases were mixed with a nonspallogenic component. The isotopic composition of Kr and Xe trapped in Canyon Diablo are shown to be type-Y, rather than the type-X Kr and Xe that is found with planetary He and Ne in mildly oxidized carbon fractions of chondrites. Large variations are observed in ratios of the light spallogenic noble gases. Spallation products in Kr and Xe tend to correlate with those in Ne, rather than in Ar, suggesting that diffusive fractionation is not responsible for variations in the 21Ne/38Ar ratio. It is suggested that portions of the material in Canyon Diablo may have been preirradiated. Xenon contains a large component of excess 129Xe and 131Xe from neutron capture on Te at energies above 0.4ev, but there is no indication that the decay of primordial 129I or the incorporation of exotic interstellar dust produced the excess 129Xe or 131Xe in our sample of Canyon Diablo. The maximum amount of excess 136Xe in our sample from fission of the hypothetical superheavy elements is shown to be 600atoms/g if the trapped Xe is atmospheric in composition; however, if the trapped Xe is AVCC, it might be as high as 6, 000atoms/g.
TL;DR: In this paper, the abundance ratios between two distinct volcanic rocks, i.e., andesite and basalt, from Oshima-Oshima and Kojima isles, Hokkaido, Japan, were determined precisely by mass-spectrometric stable isotope dilution technique.
Abstract: The REE abundances in one basalt and two andesites from Oshima-Oshima and -Kojima isles, Hokkaido, Japan, were determined precisely by mass-spectrometric stable isotope dilution technique. The abundance ratios between two distinct volcanic rocks, i.e., andesite (old somma) and basalt (young somma), from Oshima-Oshima isle show a linear function of atomic number, with breaks at Z = 68 and between 63 and 64. This can be interpreted as implying that the andesite and the basalt studied stand in a mutually conjugate relationship as possible, previously concurrent liquid and solid phases. Employing the abundance ratio function as an effective bulk partition coefficient function, the retrogressive fractionation was theoretically followed back by calculation for different FW* values. The results of calculation suggest that there were two stages concerning the relevant bulk partition coefficient functions for the development of the andesite in question and that the terrace-shaped bulk partition coefficient function with a break at Z = 67 (Ho) worked prior to the tri-segment partition coefficient function obtained directly from the abundance ratio between the andesite and the basalt.