A Sulfate-rich Model of Titan’s Interior I: Implications for the Composition of Cryomagmas

Introduction: The existing paradig the internal structure of Titan consists of overlain by an icy mantle bearing a deep ocean of aqueous ammonia [e.g., ref. 1]. regarding the possibility of cryovolcanic Titan [2], which is now apparently being b focused upon aqueous ammonia as cryomagma. Measurements of the v ammonia-water mixtures have been used cryovolcanoes and flows on Titan wi terrestrial basaltic analogues [3]. Indee candidate volcanic edifice, Ganesa Mac associated flow deposits, bear comparison deposits elsewhere in the solar system [4] the initial quantity of ammonia within Tita known, values ranging between 18 wt % component [5] to essentially zero [6]. paradigm also overlooks the plausible between the volatile fraction of Titan an soluble components (mostly sulfates) in th core during differentiation, as explored by the Jovian moons [7]. Here, we consider the consequences Kargel’s model for the Galilean moons, i leaching of sulfates from a chondritic core, containing ammonia. A new internal structure for Titan: that a chondritic core yields up 10 wt % (mostly MgSO4) that are free to go into so liquid volatile component of the early sa volatile component consists of water, am methane, and we fix NH3:CH4 = 1 fo Soluble sulfates in solution react with am water to form soluble ammonium sulfate a hydroxides. The present mass and density be reproduced from an initial rock mass 0.82; an ammonia abundance of 12.7 w volatile fraction leads to complete consump Models of the ammonia abundance inside from 1 – 18 wt %, of which a large fractio been converted to N2 and lost from the early in Titan’s history. Thus it is re hypothesise that all of Titan’s primordial am have reacted with sulfates to form ammoniu Titan’s model internal structure differentiation consists of a chondritic co 1990 km overlain by a deep liquid mantle an aqueous solution of ammonium sulfate a methane at saturation throughout the wa insoluble hydroxides have precipitated ou sediment layer ~ 40 km thick at the base o Titan also has a hot thick atmosphere Lunar and Planetary Science XXXVII (2006) 1293.pdf