Implications from Ithaca Chasma for the thermal and orbital history of Tethys
نویسندگان
چکیده
[1] Flexural modeling of Ithaca Chasma on Tethys suggests that the elastic thickness and the surface heat flux were 5–7 km and 18–30 mW/m respectively, when the feature formed ( 4 Gyr B.P.). Tidal heating is a plausible heat source, suggesting that Tethys’ eccentricity was higher in the past. Depending on Tethys’ internal structure, eccentricities in the range 0.001 to 0.02 are sufficient to have generated the inferred heat flux. Because the eccentricity damping timescale is short, < 20 Myr, it is unlikely that this eccentricity was primordial. More likely, Tethys’ eccentricity increased during passage through a 3:2 resonance with Dione. In equilibrium, this resonance produces 2.5 mW/m suggesting that non-equilibrium or periodic heating was important, similar to the case for Enceladus at present. Citation: Chen, E. M. A., and F. Nimmo (2008), Implications from Ithaca Chasma for the thermal and orbital history of Tethys, Geophys. Res. Lett., 35, L19203, doi:10.1029/2008GL035402.
منابع مشابه
Topographic Features of Ithaca Chasma , Tethys
Helfenstein, and C. C. Porco. German Aerospace Center, Institute of Planetary Research, Rutherfordstr. 2, 12489 Berlin, Germany, [email protected]; Institut für Geologische Wissenschaften, Freie Universität, 12249 Berlin, Germany; Department of Astronomy, Cornell University, Space Sciences Building, Ithaca, NY 14853, USA, Cassini Imaging Central Laboratory for Operations, Space Science Institu...
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