16: Major and trace element whole rock analyses * Major elements normalized to 100% anhydrous. # is the composition of a bulk olivine separate from ID1. ID1* is ID1 minus 4% of the olivine separate and is the liquid composition before olivine accumulation (see text). FeO is calculated assuming Fe3+/Fe2+ =0.12 *

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17: Representative olivine analyses

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18: Representative spinel analyses * Analyses have Fe3+ calculated on the basis of stoichiometry. Olivine sample numbers refer to analyses of enclosing olivine listed in Table 2. *

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19: Calculated liquidus temperature of ID1 as a function of KdFe/Mgol-1 and the Fe3+/Fe2+ of the melt

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20: Isotopic compositions of Okmok basalts * Uncertainties (in parentheses) are 2 sigma of the mean. 87Sr/86Sr is reported relative to E and A SrCO3=0.70800 and normalized to 86Sr/88Sr-0.1194. 143Nd/144Nd reported relative to BCR-1=0.51264 and normalized to 146Nd/144Nd=0.7219. Reproducibility of Pb isotopic ratios is 0.05% per AMU, in-run precision averaged 0.01%. Oxygen isotope analyses are by I. Barnes, U.S. Geological Survey. Laboratory precision for duplicate oxygen isotope analyses are typically better than 0.2 0/00. Additional delta18O values are 5.08 for a Cape Idak ferrobasalt, 6.20 for a Crater Creek ferrobasalt, and 5.89 for a young dacite. *

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