We have identified flexural uplift along the flanks of Tethys' Ithaca Chasma using Cassini stereo-derived topography. Modeling the topography as a broken elastic plate yields an effective elastic lithospheric thickness in the range of 5-7 km and, combined with the strength envelope of the lithosphere, a mechanical lithospheric thickness of 16-20 km. Surface heat fluxes are 18-30 mW/m2 for adopted strain rates of 10-17-10-14 s-1. These heat fluxes are more than 4 times higher than those calculated from thermal history models of Tethys and indicate a strongly enhanced local heat flux associated with the formation of Ithaca Chasma. We use crater-size frequency counts and a lunar-like impact chronology to fix the time of formation of Ithaca Chasma at 4 Ga from present-day. Ithaca Chasma predates the Odysseus basin and thus could not have been formed by this impact feature.
Geophysical Research Letters
- Pub Date:
- November 2007
- Planetary Sciences: Solar System Objects: Saturnian satellites;
- Planetary Sciences: Solid Surface Planets: Heat flow;
- Planetary Sciences: Solid Surface Planets: Tectonics (8149)