pH and salinity evolution of Europa's brines: Raman spectroscopy study of fractional precipitation at 1 and 300 bar.
Several lines of evidence indicate the existence of salty liquid water below the icy surface of the satellite Europa. Depending on the chemical composition of the original interior brines, minerals that precipitate will be varied as will be the resulting physicochemical parameters of the evolving solutions such as pH and salinity. These parameters are determinants apropos to the study of the possible habitability of the satellite. In this work, experiments of fractional precipitation by cooling of several brines with different chemical composition (acid, alkaline, and neutral) were performed at 1 and 300 bar. The gradual decrease in temperature leads to mineral precipitation and changes in salinity and pH values. During the experiment, Raman spectroscopy was used to analyze quantitatively the variation of the salt concentration in the aqueous solutions. The obtained laboratory data indicate the manner in which cryomagma differentiation might occur on Europa. These endogenous processes of differentiation require planetary energy, which seems to have been plentiful during Europa's geological history. Ultimately, the dissipation of part of that energy is translated to a higher complexity of the cryopetrology in Europa's crust. From the results, we conclude that fractional differentiation processes of briny cryomagmas produce several types of igneous salty mineral suites on icy moons.
Departamento de Química Física I, Universidad Complutense de Madrid, Madrid, Spain. victoria.munoz@cab.inta-csic.es
Victoria
V
Muñoz-Iglesias
Laura J
LJ
Bonales
Olga
O
Prieto-Ballesteros
D002254:Carbonates / Q000737:chemistry*; D005590:Fractional Precipitation; D006863:Hydrogen-Ion Concentration; D018538:Jupiter; D054712:Salinity; D012623:Seawater / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013431:Sulfates / Q000737:chemistry*
D002254:Carbonates; D013431:Sulfates; C005686:sodium carbonate