thumbnail

Noble gas systematics for coexisting glass and olivine crystals in basalts and dunite xenoliths from Loihi Seamount

Earth and Planetary Science Letters

By:
, , and

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time
  • Download citation as: RIS

Abstract

Noble gas isotopes including 3He 4He, 40Ar 36Ar and Xe isotope ratios were determined for coexisting glass and olivine crystals in tholeiitic and alkalic basalts and dunite xenoliths from Loihi Seamount. Glass and coexisting olivine crystals have similar 3He 4He ratios (2.8-3.4) ?? 10-5, 20 to 24 times the atmospheric ratio (RA), but different 40Ar 36Ar ratios (400-1000). Based on the results of noble gas isotope ratios and microscopic observation, some olivine crystals are xenocrysts. We conclude that He is equilibrated between glass and olivine xenocrysts, but Ar is not. The apparent high 3He 4He ratio (3 ?? 10-5; = 21 RA) coupled with a relatively high 40Ar 36Ar ratio (4200) for dunite xenoliths (KK 17-5) may be explained by equilibration of He between MORB-type cumulates and the host magma. Except for the dunite xenoliths, noble gas data for these Loihi samples are compatible with a model in which samples from hot spot areas may be explained by mixing between P (plume)-type and M (MORB)-type components with the addition of A (atmosphere)-type component. Excess 129Xe has not been observed due to apparent large mass fractionation among Xe isotopes. ?? 1983.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Noble gas systematics for coexisting glass and olivine crystals in basalts and dunite xenoliths from Loihi Seamount
Series title:
Earth and Planetary Science Letters
Volume
66
Issue:
C
Year Published:
1983
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Earth and Planetary Science Letters
First page:
427
Last page:
437