New Archaeomagnetic Data In Mexico
Abstract
The mean densities of Ganymede, Callisto, and Titan indicate that their interiors are composed of ice and silicates at nearly equal shares by mass. However, Titan's sub- stantial nitrogen atmosphere suggests that the satellite's interior is more enriched in volatiles such as NH3 in comparison to those of Ganymede and Callisto. As a conse- quence of substantial accretional heating, the interior of Titan may be differentiated into a rocky core and an icy mantle. Depending on the amount of volatiles incorpo- rated into the icy mantle and the satellite's thermal evolution, an ammonia-rich water layer may be presently situated beneath Titan's icy crust. Therefore, we assume the interior of Titan to consist of a rocky core with chondritic heat production underneath a high-pressure ice layer, an isothermal sub-surface ocean, and an outermost ice I shell being further subdivided into a conductive (stagnant) lid and a convective sub-layer. Taking the assumption of thermal equilibrium, we obtain a surface heat flow of the order of several 1011 W, and the thickness of the stagnant lid and the well-mixed con- vective sublayer from a parameterized model of convective heat transfer. We consider various compositions of the sub-surface ocean and calculate moment of inertia factors of about 0.3 and tidal Love numbers k2 and h2 for the resulting interior structure mod- els. k2 varies between 0.35 to 0.4 and h2 ranges from 1.1 to 1.3 in these models. The Love numbers generally increase with increasing heat production in the core because the sub-surface ocean thickness increases at the expense of the high-pressure ice layer and the outermost ice I shell, thereby providing greater flexibility to the ice I layer.
- Publication:
-
EGS General Assembly Conference Abstracts
- Pub Date:
- 2002
- Bibcode:
- 2002EGSGA..27.6498S