Relationships of Dione's physical and chemical surface properties to geological and morphological surface features

Stephan, K.; Jaumann, R.; Wagner, R.; Roatsch, T.; Brown, B.; Buratti, B. B.; Roger, C. N.; Nicholson, P. D.; Baines, K. H.
Bibliographical reference

American Geophysical Union, Fall Meeting 2007, abstract #P21B-0547

Advertised on:
12
2007
Number of authors
9
IAC number of authors
0
Citations
0
Refereed citations
0
Description
During orbit DI 016 (October 2005) Cassini's Visual and Infrared Mapping Spectrometer (VIMS) [1] acquired spatially resolved spectral data of the Saturnian satellite Dione with pixel ground resolutions up to 2 km per pixel. Additionally, the Imaging Science Subsystem (ISS) [2] observed the satellite synchronously to VIMS with pixel ground resolutions up to 15 m per pixel. Based on high resolution VIMS data we mapped the chemical and physical properties across Dione's surface. In order to study the relationships between the spectral characteristics of the surface material and geological processes it is essential to relate the spectral information to geological and geomorphological surface features. Therefore we reprojected and mosaicked the resulting VIMS maps [3] and registered them to the simultaneously acquired ISS images. Resulting VIMS/ISS maps show pronounced spectral differences which can be correlated with geological units and are found in the vicinity of stratigraphically younger impact craters and tectonic features (troughs and "wispy streaks") indicating exposed water ice from underneath. Globally abundant cratered plains are well distinguishable from the tectonically deformed regions and show the highest influence of dark material [4]. Although ISS data indicate different subunits of the cratered plains with respect to morphology and ages [5], these subunits are indistinguishable in the VIMS data. In contrast their spectral characteristics appear to be only related to hemispherical differences. [1] Brown R.H. et al., SSR, 115, 111-168, 2004. [2] Porco C.C. et al., SSR, 115, 363-497, 2004. [3] Jaumann et al., PSS, 54, 1146-1155, 2006. [4] Clark R.N. et al. (Icarus, in press). [5] Wagner R. et al., LPSC XXXVII, abstract 1805.