Research Article
Subcritical Phase Separation and Occurrence of Deep-Seated Brines at the NW Caldera Vent Field, Brothers Volcano: Evidence from Fluid Inclusions in Hydrothermal Precipitates
Table 4
Characteristics of coexisting hydrothermal end-member vapor-brine pairs used in our best-fit isenthalpic mixing model. Temperature, pressure, and salinities (, in wt.% NaCl eq.) were derived from the L+V surface of the H2O-NaCl system [57]. and (mass fractions in the corresponding vapor and brine pairs) were calculated by the lever rule and by assuming a source fluid with seawater salinity. The Sr concentrations (mmol kg-1) of the vapor-brine pairs were calculated by assuming Sr partitioning behavior identical to that of salt and using a seawater Sr concentration of 0.09 mmol kg-1; the 87Sr/86Sr value of 0.7044 () for the hydrothermal end-member was derived from 10 hydrothermal fluid samples by back calculating to [47].
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