Detailed chemical composition analysis of the Soi crater region on TitanShow others and affiliations
2024 (English)In: Icarus, ISSN 0019-1035, E-ISSN 1090-2643, Vol. 421, article id 116215Article in journal (Refereed) Published
Abstract [en]
The Soi crater region (0° to 60°N, 180°W to −110°W), which includes the well-preserved Soi crater in its center, spans a region from Titan's aeolian-dominated equatorial regions to fluvially-dominated high northern latitudes. This provides a rich diversity of landscapes, one that is also representative of the diversity encountered across Titan. Schoenfeld et al. (2023) mapped this region at 1:800,000 scale and produced a geomorphological map showing that the area consists of 22 types of geomorphological units. The Visual and Infrared Mapping Spectrometer (VIMS) coverage of the region enabled the detailed analysis of spectra of 261 different locations using a radiative transfer technique and a mixing model, yielding compositional constraints on Titan's optical surface layer. Additional constraints on composition on the near-surface substrate were obtained from microwave emissivity. We have derived combinations of top surface materials between dark materials, tholins, water-ice, and methane suggesting that dark mobile organic material at equatorial and high latitudes indicates “young” terrains and compositions, while tholin/water-ice mixtures that dominate areas around latitude 35°N show a material that is older plains deposits that we interpret to be the end stage of aeolian and fluvial transport and deposition. We found no spectral evidence of CO2, HC3N, and NH3 ice. We use the stratigraphic relations between the various mapping units and the relation between the geomorphology and the composition of the surface layers to build hypotheses on the origin and evolution of the regional geology. We suggest that sedimentary deposits, likely aeolian, are dominant in the region with fluvial activity and leaching changing the nature of the top surfaces of the midlatitude areas of the Soi crater region.
Place, publisher, year, edition, pages
Elsevier BV , 2024. Vol. 421, article id 116215
Keywords [en]
Icy satellites, Ocean worlds, Radiative transfer, Surface composition, Titan
National Category
Astronomy, Astrophysics and Cosmology Geology
Identifiers
URN: urn:nbn:se:kth:diva-351915DOI: 10.1016/j.icarus.2024.116215ISI: 001288253500001Scopus ID: 2-s2.0-85200225065OAI: oai:DiVA.org:kth-351915DiVA, id: diva2:1890131
Note
QC 20240827
2024-08-192024-08-192024-09-05Bibliographically approved