Unknown
PANGAEA
In:
Supplement to: Sato, Hiroaki (1989): Mg-Fe partitioning between plagioclase and liquid in basalts of Hole 504B, ODP Leg 111: a study of melting at 1 ATM. In: Becker, K; Sakai, H; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 111, 17-26, https://doi.org/10.2973/odp.proc.sr.111.113.1989
Publication Date:
2024-01-09
Description:
The effect of oxygen fugacity (fO2) on the partition relationship of Mg and Fe between Plagioclase and sillicate liquid was investigated at 1 atm for basaltic samples recovered during ODP Leg 111 from Hole 504B. Samples 111-504B-143R-2 (Piece 8) and 111-504B-169R-1 (Piece 1) have Plagioclase as the liquidus phase. The distribution coefficient of Mg between Plagioclase and melt is constant at about 0.04 against the variation of fO2, whereas that of Fe (total Fe) varies from 0.3 at f(O2) = 0.2 atm to 0.03 at f(o2) = 10**-11.5 at 1200°C. The distribution coefficient of Mg is slightly higher than that calculated from the phenocryst and bulk-rock compositions, suggesting a kinetic disequilibrium effect on the distribution of Mg in Plagioclase. Because Mg, Fe, and Fe3+ have similar diffusion coefficients in silicate melt, the disequilibrium effect is greatly reduced for the exchange reaction of Mg and total Fe between Plagioclase and liquid. The exchange partition coefficient is highly dependent on fo2, with log fo2 ranging from -0.7 to - 11.5 at approximately 1200°C. Using this relationship, the f(O2) of crystallization of the magmas is estimated to be near the one defined by the fayalite-quartz-magnetite assemblage.
Keywords:
111-504B; DRILL; Drilling/drill rig; Joides Resolution; Leg111; North Pacific Ocean; Ocean Drilling Program; ODP
Type:
Dataset
Format:
application/zip, 3 datasets
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