Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution

Details Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution

Mar 1996

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996lpi....27..819m&link_type=abstract

Lunar and Planetary Science, volume 27, page 819

Computer Science

Atmospheres: Primitive, Earth: Atmosphere, Earth: Mantle, Isotopes: Nitrogen

Scientific paper

The isotopic composition of terrestrial nitrogen in the silicate Earth is not well known, which precludes quantitative treatment of the atmospheric nitrogen evolution. In order to document it, we have performed a static mass spectrometry analysis of rare gas and nitrogen contents and isotopic ratios in mantle-derived samples. Gases were extracted by stepwise crushing of oceanic basalt glasses, a procedure which minimises the contribution of nitrogen added to the samples after lava eruption. All data can be explained by mixing between a surface component (40Ar/36Ar ratios close to the atmospheric value and delta 15N values close to 0 per mil, the atmospheric composition by definition, or slightly positive) and a mantle component with 40Ar/36Ar ratios up to 42,000 and delta 15N = -4.5 +/- 0.5 per mil. The mantle component is also characterised by a N2/40Ar +/- ratio (where 40Ar has been produced during Earth's history by the decay of 40K) comparable to the atmospheric N2/40Ar ratio, but by a N2/36Ar ratio (where 36Ar is a primordial isotope of argon) two orders of magnitude higher than the corresponding air ratio. These observations are used to constrain the early state of the terrestrial atmosphere : nitrogen in the primitive atmosphere was probably enriched in 15N, with a lower limit for its delta 15N value of +20 per mil.

Affiliated with

Also associated with

No associations

Rating

Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nitrogen Isotopic Composition of the Silicate Earth and its Bearing on Earth-Atmosphere Evolution will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1613463