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| Titel |
Titan's Sand Seas properties from the modelling of microwave-backscattered signal of Cassini/SAR |
| VerfasserIn |
Antoine Lucas, Sebastien Rodriguez, Florentin Lommonier, Cécile Ferrari, Philippe Paillou, Alice Le Gall, Clement Narteau |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250133478
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| Publikation (Nr.) |
 EGU/EGU2016-14093.pdf |
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| Zusammenfassung |
| Titan’s sand seas may reflect the current and past surface conditions. Assessing the
physicochemical properties and the morphodynamics of the equatorial linear dunes is a
milestone in our comprehension of the climatic and geological history of the largest Saturn’s
moon.
Based on enhanced SAR processing leading to despeckled Cassini RADAR
data sets, we analyzed quantitatively the surface properties (e.g., slopes, texture,
composition...) over the sand seas. First, using a large amount of overlaps and a wide range
of incidence angle and azimuths, we show that the radar cross-section over the
inter-dunes strongly differs from the one over the dunes. This strongly suggests
significant difference in the physical properties between these two geomorphic
units.
Then, we derived quantitatively the surface properties from the modelling of
microwave-backscattered signal using a Monte-Carlo inversion. Our results show that dunes
are globally more microwaves absorbent than the inter-dunes. The inter-dunes are smoother
with a higher dielectric constant than the dunes. Considering the composition, the
inter-dunes are in between the dunes and the bright inselbergs mainly composed of
water ice, suggesting the presence of a shallow layer of sediment in between the
dunes. This may suggest that Titan dunes are developing over a coarser sediment
bed similarly to what is observed in some terrestrial sand seas such as in Ténéré
desert (Niger, see also contribution #EGU2016-13383). Additionally, potential
secondary bedforms (such as ripples) as well as avalanche faces may have been
detected. |
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