An experimental system we developed combines triaxial rock deformation and mass spectrometry to measure noble gas flow before, during, and after rock fracture. Gas flow through a granite and basalt in its unfractured condition allows estimation of “native” permeability. Geogenic noble gas is released during triaxial deformation (real time) and is related to volume strain and acoustic emissions....

Introduction: Chondrules were formed by rapid cooling of silicate melt about 4.6 Ga, and have held their spherical shapes until to the present. Chondrules are free from trapped noble gases [e.g., 1], which is believed to be due to complete degassing during the chondrule formation. Owing to the absence of trapped noble gases, cosmogenic noble gases can be detected clearly. Cosmogenic noble gases...

[1] Noble gas paleoclimate reconstructions from noble gas concentrations in groundwater have the promise of providing absolute paleotemperature information, but difficulties in modeling measured noble gas concentrations with simple models have led to a number of competing noble gas temperature (NGT) schemes being developed. These different models make different assumptions about the size and na...

Noble gases have attributes and properties that make them very attractive as tracers for fluid movement and reservoir processes. Noble gases are non-reactive and most of them have no sinks or sources in the subsurface, rendering them conservative. They occur naturally in waters that have been in contact with the atmosphere in concentrations that depend on their solubilities. As solubilities are...

Noble-gas chemistry has been undergoing a renaissance in recent years, due in large part to noble-gas hydrides, HNgY, where Ng = noble-gas atom and Y = electronegative fragment. These molecules are exceptional because of their relatively weak bonding and large dipole moments, which lead to strongly enhanced effects of the environment, complexation, and reactions. In this Account, we discuss the...

Although the naturally occurring atmospheric noble gases He, Ne, Ar, Kr, and Xe possess great potential as tracers for studying gas exchange in living beings, no direct analytical technique exists for simultaneously determining the absolute concentrations of these noble gases in body fluids in vivo. In this study, using human blood as an example, the absolute concentrations of all stable atmosp...

The structural stability of pure SnO2 nanoparticles and highly sensitive SnO2-SiO2 nanocomposites (0-15 SiO2 wt%) has been investigated for conditions relevant to their utilization as chemoresistive gas sensors. Thermal stabilization by SiO2 co-synthesis has been investigated at up to 600 °C determining regimes of crystal size stability as a function of SiO2-content. For operation up to 400 °C,...

Noble gases are mostly known as inert monatomic gases due to their limited reactivity with other elements. However, the first predictions of noble-gas compounds were suggested by Kossel in 1916, by von Antropoff in 1924, and by Pauling in 1930. It took many decades until the first noble-gas compound, XePtF6, was synthesized by Neil Bartlett in 1962. This was followed by gradual development of t...

[1] A key assumption for calculating paleotemperatures using noble gas concentrations in groundwater is that water equilibrates with standard air. However, if the unsaturated zone is depleted in O2, the noble gas partial pressures will be elevated, resulting in a bias of noble gas temperatures (NGTs) to low values. This oxygen depletion (OD) mechanism was used to explain low NGT values for a sh...