Bright carbonate surfaces on Ceres as remnants of salt-rich water fountains
Vinalia and Cerealia Faculae are bright and salt-rich localized areas in Occator crater on Ceres. The predominance of the near-infrared signature of sodium carbonate on these surfaces suggests their original material was a brine. Here we analyze Dawn Framing Camera's images and characterize the surfaces as composed of a central structure, either a possible depression (Vinalia) or a central dome (Cerealia), and a discontinuous mantling. We consider three materials enabling the ascent and formation of the faculae: ice ascent with sublimation and carbonate particle lofting, pure gas emission entraining carbonate particles, and brine extrusion. We find that a mechanism explaining the entire range of morphologies, topographies, as well as the common composition of the deposits is brine fountaining. This process consists of briny liquid extrusion, followed by flash freezing of carbonate and ice particles, particle fallback, and sublimation. Subsequent increase in briny liquid viscosity leads to doming. Dawn observations did not detect currently active water plumes, indicating the frequency of such extrusions is longer than years.
Citation Information
Publication Year | 2019 |
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Title | Bright carbonate surfaces on Ceres as remnants of salt-rich water fountains |
DOI | 10.1016/j.icarus.2018.01.022 |
Authors | Ottavian Ruesch, Lynnae Quick, Margaret Evelyn Landis, M.M. Sori, O. Čadek, P. Brož, K.A. Otto, Michael T. Bland, S. Byrne, J.C. Castillo-Rogez, H. Hiesinger, R. Jaumann, K. Krohn, L.A. McFadden, A. Nathues, A. Neesemann, F. Preusker, T. Roatsch, P.M. Schenk, J.E.C. Scully, M.V. Sykes, D.A. Williams, C.A. Raymond, C.T. Russell. |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Icarus |
Index ID | 70212305 |
Record Source | USGS Publications Warehouse |
USGS Organization | Astrogeology Science Center |