Helium concentration and isotopic composition were measured in a suite of samples across the Permian–Triassic boundary at Opal Creek, Canada, to determine whether high extraterrestrial helium concentrations are associated with a possible extinction-inducing impact event at this time. No extraterrestrial [super]3He was detected, implying that neither fullerene-hosted nor IDP-hosted He is present at or near the boundary. This observation is consistent with similar studies of some Permian–Triassic sections, but contrasts sharply with reports of both fullerene- and IDP-hosted extraterrestrial [super]3He at other sections. Step-heat experiments indicate rapid diffusion of extraterrestrial helium from sediments heated to temperatures above ~70 °...
The end-Permian mass extinction (251 Ma) was the largest in Earth's history, and the great extent of...
Two decades ago, Merrihue (1964) reported 3He/4He ratios of >10**-4 in ferromagnetic separates from ...
Helium-3 in hotspot magmas has been used as unambiguous evidence for the existence of a primordial, ...
Helium concentration and isotopic composition were measured in a suite of samples across the Permian...
We have measured the helium abundance and isotopic composition of a suite of Lower Ordovician marine...
To better understand the composition, characteristics of helium diffusion, and size distribution of ...
Helium-3 concentrations and ^3He/^4He ratios in modern pelagic sediments are known to be far in exce...
Almost 40 years after the discovery of extraterrestrial helium in seafloor sediments, renewed atten...
Becker et al. (1) presented geochemical evidence that suggests that the largest mass extinction in E...
Abstract The ca 252 Ma Permian–Triassic boundary (PTB) represents the most severe mass extinction ev...
We present a theoretical basis for reconstructing paleotemperatures from the open-system behavior of...
Consideration of the geosphere for isolation of nuclear waste has generated substantial interest in ...
International audienceThe observed escape of the primordial helium isotope, 3He, from the Earth's in...
We attempt to constrain the variability of the flux of extraterrestrial 3He in the Paleocene by stud...
Among the isotope systems exploited by mantle geochemists to deduce the chemical evolution of the Ea...
The end-Permian mass extinction (251 Ma) was the largest in Earth's history, and the great extent of...
Two decades ago, Merrihue (1964) reported 3He/4He ratios of >10**-4 in ferromagnetic separates from ...
Helium-3 in hotspot magmas has been used as unambiguous evidence for the existence of a primordial, ...
Helium concentration and isotopic composition were measured in a suite of samples across the Permian...
We have measured the helium abundance and isotopic composition of a suite of Lower Ordovician marine...
To better understand the composition, characteristics of helium diffusion, and size distribution of ...
Helium-3 concentrations and ^3He/^4He ratios in modern pelagic sediments are known to be far in exce...
Almost 40 years after the discovery of extraterrestrial helium in seafloor sediments, renewed atten...
Becker et al. (1) presented geochemical evidence that suggests that the largest mass extinction in E...
Abstract The ca 252 Ma Permian–Triassic boundary (PTB) represents the most severe mass extinction ev...
We present a theoretical basis for reconstructing paleotemperatures from the open-system behavior of...
Consideration of the geosphere for isolation of nuclear waste has generated substantial interest in ...
International audienceThe observed escape of the primordial helium isotope, 3He, from the Earth's in...
We attempt to constrain the variability of the flux of extraterrestrial 3He in the Paleocene by stud...
Among the isotope systems exploited by mantle geochemists to deduce the chemical evolution of the Ea...
The end-Permian mass extinction (251 Ma) was the largest in Earth's history, and the great extent of...
Two decades ago, Merrihue (1964) reported 3He/4He ratios of >10**-4 in ferromagnetic separates from ...
Helium-3 in hotspot magmas has been used as unambiguous evidence for the existence of a primordial, ...