Primordial helium and neon in the Earth - a speculation on early degassing

被引：45

作者：

Honda, M ^{[1
]}

McDougall, I ^{[1
]}

机构：

[1] Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT 0200, Australia

来源：

GEOPHYSICAL RESEARCH LETTERS | 1998年 / 25卷 / 11期

关键词：

D O I：

10.1029/98GL01329

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Primordial helium-neon abundance ratios in the Earth have been accurately determined, based on helium and neon isotopic systematics observed in mid-ocean ridge basalts (MORBs) and Hawaiian ocean island basalt (OIB) samples. The mean primordial He-3/Ne-22 ratios for the MORE and Hawaiian OIB samples are 10.2 +/- 1.6 and 6.0 +/- 1.4, respectively. The gross average of all values is 7.7 +/- 2.6, about twice the solar He-3/Ne-22 ratio of 3.8. Thus, primordial helium and neon in the Earth are elementally fractionated from the solar composition, noting, however, that the Earth's primordial helium and neon are isotopically solar in composition. This elemental fractionation between helium and neon was probably caused by solubility-controlled degassing processes at an early stage of the Earth's evolution.

引用

页码：1951 / 1954

页数：4

共 32 条

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