Reequilibration of chromite within Kilauea Iki lava lake, Hawaii

Contributions to Mineralogy and Petrology
By: , and 

Links

Abstract

Chromite mainly occurs as tiny inclusions within or at the edges of olivine phenocrysts in the 1959 Kilauea Iki lava lake. Liquilus chromite compositions are only preserved in scoria that was rapidly quenched from eruption temperatures. Analyses of drill core taken from the lava lake in 1960, 1961, 1975, 1979, and 1981 show that chromite becomes richer in Fe+2, Fe+3, Ti and poorer in Mg, Al, Cr than the liquidus chromite. The amount of compositional change depends on the time elapsed since eruption, the cooling history of the sample, the extent of differentiation of the interstitial melt, and the position of the chromite inclusion within the olivine phenocryst. Compositional changes of the chromite inclusions are thought to be a result of reequilibration with the residual melt by cationic diffusion (Mg, Al, Cr outwards and Fe+2, Fe+3, Ti inwards) through olivine. The changing chemical potential gradients produced as the residual melt cools, crystallizes and differentiates drives the reequilibration process. Major and minor element zoning profiles in olivine phenocrysts suggest that volume diffusion through olivine may have been the major mechanism of cationic transport through olivine. The dramatic compositional changes observed in chromite over the 22 years between eruption and 1981 has major implications for othe molten bodies. ?? 1991 Springer-Verlag.
Publication type Article
Publication Subtype Journal Article
Title Reequilibration of chromite within Kilauea Iki lava lake, Hawaii
Series title Contributions to Mineralogy and Petrology
DOI 10.1007/BF00311181
Volume 107
Issue 1
Year Published 1991
Language English
Publisher location Springer-Verlag
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Contributions to Mineralogy and Petrology
First page 8
Last page 20
Google Analytic Metrics Metrics page
Additional publication details