INITIAL GEOLOGIC MAPPING OF THE AC-H-11 SINTANA QUADRANGLE OF CERES USING DAWN SPACECRAFT DATA

The method of geologic mapping is applied to Ceres' quadrangle Ac-H-11 Sintana in order to assess the underlying processes forming Ceres' surface. The base data used in this study are clear-filter and color-filter ratio images derived from the Framing Camera onboard the Dawn spacecraft, supported by digital elevation models. The Survey Orbit in June 2015 provides the current highest resolution images (415 m/px). The High and Low Altitude Mapping Orbits will deliver enhanced quality. Visible and infrared spectroscopic data will contribute to compositional interpretation.

Ac-H-11 Sintana, one of 15 mapping quadrangles, is located in Ceres' southern hemisphere between 21-66°S and 0-90°E. The dominant feature is an alignment of three craters in the topographically lower center of the quadrangle. These craters illustrate the variety of crater forms, inner crater structures and symmetries, such as terraced walls and central structures. There are numerous central peaks, for example inside the crater Sintana. The largest craters in the quadrangle reveal more complex inner structures and flat floors. Great variation in the slopes of crater walls and degradation states of crater rims can be found. Initial mapping reveals mass wasting features, such as landslides. Information about surface composition and local tectonics might be inferred from single positive topography features. A prominent example is located to the south of the Sintana crater. We will identify the types of linear structures and analyze them in terms of possible predominant directions. Different ratios of color-filter images suggest a major geological boundary in the NE of the quadrangle. Increasingly higher resolution data during the Dawn mission will provide an opportunity to draw a link between all single observations.

We thank I. von der Gathen, E. Kersten, K.-D. Matz, A. Naß, K. Otto, C.M. Pieters, M.C. De Sanctis, S. Schröder, K. Stephan, R. J. Wagner, C.A. Raymond and C.T. Russell.