(Table 1) Helium concentration in sediments

Two decades ago, Merrihue (1964) reported 3He/4He ratios of >10**-4 in ferromagnetic separates from a Pacific deep ocean red clay and concluded that the high ratio is due to extraterrestrial debris amounting to ~1% of the sediment. A decade later Krylov et al. (1973) compiled 3He/4He isotopic data on ocean sediments measured in the Soviet Union and observed that the 3He/4He ratio is generally higher in pelagic sediments where the sedimentation rate is lower. They suggested that the high 3He/4He ratio was attributable to extraterrestrial materials which were concentrated in slowly accumulating ocean floor. However, these important discoveries were almost completely neglected until we re-examined the problem. We have measured 39 sediments from 12 different sites, 10 sites from the western to central Pacific and two sites from the Atlantic Ocean. We find 3He/4He ratios >5 * 10**-5 for six sites, well above the values generally observed in common terrestrial materials. The very high 3He/4He ratio in the sediments is probably due to input of extraterrestrial materials. Input of stratospheric dust of <1 p.p.m., which corresponds to a fallout rate of ~2,000 tons per year, can explain the observation.

Helium isotope ratios and pore gases in deep-sea sediments of the Japan Sea

We have measured the 3He/4He and 4He/20Ne ratios and chemical compositions of gases exsolved from deep-sea sediments at two sites (798 and 799) in the Japan Sea. The 3He/4He and 4He/20Ne ratios vary from 0.642 Ratm (where Ratm is the atmospheric 3He/4He ratio of 1.393*10**-6) to 0.840 Ratm, and from 0.41 to 4.5, respectively. Helium in the samples can be explained by the mixing between atmospheric helium dissolved in bottom water of the Japan Sea and crustal helium in the sediment. The sedimentary helium is enriched in mantle-derived 3He compared with those from the Japan Trench and the Nankai Trough. This suggests that the basement of the Japan Sea has relatively large remnants of mantle-derived helium compared with that of the Pacific. Major chemical compositions of the samples are methane and nitrogen. There is a positive correlation between methane content and helium content corrected for air component. Based on the 3He/4He-Sum C/3He diagram, the major part of methane can be attributed to crustal and/or organic origin.

Products of high-energy deuteron and helium ion bombardments of copper /

Work performed at the University of California.

The effects of intense gamma irradiation on electric breakdown in helium /

"Physics Development Department, Tracerlab, Incorporated, Reactor Monitoring Center."

The purification and gas chromatographic analysis of helium /

"Issued June 30, 1961."

The solubility of helium in lithium and potassium /

"Contract AT(30-1)-2789."

The Anabasis of Xenophon : with an interlinear translation, for the use of schools and private learners on the Hamiltonian system /

Mode of access: Internet.

HARPA : a versatile three-dimensional Hamiltonian ray-tracing program for acoustic waves in the atmosphere above irregular terrain /

Mode of access: Internet.

Helium research in support of superconducting power transmission : annual report for the period October 1, 1978-September 30, 1979 /

Includes bibliographical references.

Helium injection into the boundary layer at an axisymmetric stagnation point

"Contract no. AF 33(616)-7661, Project no. 7064, Task no. 70169."

A treatise on logic, or, The laws of pure thought : comprising both the Aristotelic and Hamiltonian analyses of logical forms, and some chapters of applied logic /

Mode of access: Internet.

Historiæ sacræ; adapted to the Hamiltonian system by an interlineary and literal translation.

Mode of access: Internet.

A treatise on logic : or, The laws of pure thought; comprising both Aristotelic and Hamiltonian analyses of logical forms, and some chapters of applied logic /

Mode of access: Internet.

The thermodynamic properties of helium from 3 to 300⁰ K between 0.5 and 100 atmospheres

Bibliography: p. 13-14.

The thermodynamic properties of helium from 6 to 540⁰ R between 10 and 1500 psia /

Supplementary ed. of NBS technical note 154 "and presents the same data in the dimensional units of the British system."