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Showing 1 to 5 of 5 for “"Helium isotopes"”.
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Diffusion of helium isotopes in silicate glasses and minerals : implications for petrogenesis and geochronology
Helium mobility in geologic materials is a fundamental constraint on the petrogenetic origins of helium isotopic variability and on the application of radiogenic and cosmogenic helium geochronology. 3He and 4He volume diffusivities determined at 25-600°C in basaltic glasses by incremental-heating …
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Diffusion of helium isotopes in silicate glasses and minerals : implications for petrogenesis and geochronology
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1989.
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A determination of air-sea gas exchange and upper ocean biological production from five noble gases and tritiugenic helium-3
The five noble gases (helium, neon, argon, krypton, and xenon) are biologically and chemically inert, making them ideal oceanographic tracers. Additionally, the noble gases have a wide range of solubilities and molecular diffusivities, and thus respond differently to physical forcing. Tritium, an …
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A determination of air-sea gas exchange and upper ocean biological production from five noble gasses and tritiugenic helium-3
The five noble gases (helium, neon, argon, krypton, and xenon) are biologically and chemically inert, making them ideal oceanographic tracers. Additionally, the noble gases have a wide range of solubilities and molecular diffusivities, and thus respond differently to physical forcing. Tritium, an …
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Helium isotope geochemistry of oceanic volcanic rocks : implications for mantle heterogeneity and degassing
The concentrations and isotopic compositions of helium have been measured in a number of mantle derived oceanic basalts. The goal of this research is to use the helium isotopic systematics to constrain the nature and origin of mantle heterogeneity in the oceanic mantle. Studies of helium …