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Slurry extrusion on Ceres from a convective mud-bearing mantle


Ceres is a 940-km-diameter dwarf planet that is predominantly composed of silicates and water ice. In Ceres’ partially differentiated interior, extrusive processes have led to the emplacement on its surface of domes with heights of kilometres. Here we report the analysis of a gravity anomaly detected by the Dawn spacecraft, which is associated with the geologically recent dome Ahuna Mons. By modelling the anomaly with a mass concentration method, we determine that the subsurface structure includes a regional mantle uplift, which we interpret as a plume. This structure is the probable source of fluids forming Ahuna Mons and, together with constraints from the dome’s morphology, indicates a rheological regime corresponding to a slurry of brine and solid particles. We propose that the properties of such a solid–liquid mixture can explain the viscous relaxation and the mineralogy of the dome. The presence of a plume and of slurry material indicate recent convection in a mud-bearing mantle. The inferred slurry extrusion on Ceres differs from the water-dominated cryovolcanism of icy satellites, and so reveals compositional and rheological diversity in extrusive phenomena on planetary surfaces.

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Data availability

The data Ceres18C described in ref. 5 used in this study are available at

The Ceres HAMO Digital Terrain Model described in ref. 8 used in this study is available at

Code availability

The computer codes associated with this paper are presented in Methods.

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  1. 1.

    Russell, C. T. et al. Dawn arrives at Ceres: exploration of a small, volatile-rich world. Science 353, 1008–1010 (2016).

  2. 2.

    Castillo-Rogez, J. C. & McCord, T. B. Ceres’ evolution and present state constrained by shape data. Icarus 205, 443–459 (2010).

  3. 3.

    Park, R. S. et al. A partially differentiated interior for (1) Ceres deduced from its gravity field and shape. Nature 537, 515 (2016).

  4. 4.

    Konopliv, A. S. et al. The Ceres gravity field, spin pole, rotation period and orbit from the Dawn radiometric tracking and optical data. Icarus 299, 411–429 (2017).

  5. 5.

    Ermakov, A. I. et al. Constraints on Ceres’ internal structure and evolution from its shape and gravity measured by the Dawn spacecraft. J. Geophys. Res. 122, 2267–2293 (2017).

  6. 6.

    Mao, X. & McKinnon, W. B. Faster paleospin and deep-seated uncompensated mass as possible explanations for Ceres’ present-day shape and gravity. Icarus 299, 430–442 (2017).

  7. 7.

    Fu, R. R. et al. The interior structure of Ceres as revealed by surface topography. Earth Planet. Sci. Lett. 476, 153–164 (2017).

  8. 8.

    Roatsch,T. et al. DAWN FC2 DERIVED CERES HAMO DTM SPG V1.0, DAWN-A-FC2-5-CERESHAMODTMSPG-V1.0 (NASA Planetary Data System, 2016).

  9. 9.

    Ruesch, O. et al. Cryovolcanism on Ceres. Science 353, aaf4286 (2016).

  10. 10.

    Zambon, F. et al. Spectral analysis of Ahuna Mons from Dawn mission’s visible‐infrared spectrometer. Geophys. Res. Lett. 44, 97–104 (2017).

  11. 11.

    Tricarico, P. True polar wander of Ceres due to heterogeneous crustal density. Nat. Geosci. 11, 819–824 (2018).

  12. 12.

    Formisano, M., Federico, C., De Andelis, S., De Sanctis, M. C. & Magni, G. The stability of the crust of the dwarf planet Ceres. Mon. Not. R. Astron. Soc. 463, 520–528 (2016).

  13. 13.

    Neumann, W., Breuer, D. & Spohn, T. Modelling the internal structure of Ceres: coupling of accretion with compaction by creep and implications for the water-rock differentiation. Astron. Astrophys. 584, A117 (2015).

  14. 14.

    Mazarico, E. et al. The gravity field, orientation, and ephemeris of Mercury from MESSENGER observations after three years in orbit. J. Geophys. Res. 119, 2417–2436 (2014).

  15. 15.

    Melosh, H. J. et al. The origin of lunar mascon basins. Science 340, 1552–1555 (2013).

  16. 16.

    Bland, M. T. et al. Morphological indicators of a mascon beneath Ceres’ largest crater, Kerwan. Geophys. Res. Lett. 45, 1297–1304 (2018).

  17. 17.

    Marchi, S. et al. The missing large impact craters on Ceres. Nat. Commun. 7, 12257 (2016).

  18. 18.

    Travis, B. J., Bland, P. A., Feldman, W. C. & Sykes, M. V. Hydrothermal dynamics in CM-based model of Ceres. Meteorit. Planet. Sci. 53, 2008–2032 (2018).

  19. 19.

    Quick, L. C. et al. A possible brine reservoir beneath Occator crater: thermal and compositional evolution and the formation of the Vinalia Faculae. Icarus 320, 119–135 (2019).

  20. 20.

    Davis, D. W., Lowenstein, T. K. & Spencer, R. J. Melting behavior of fluid inclusions in laboratory-grown halite crystals in the systems NaCl–H2O, NaCl–KCl–H2O, NaCl–MgCl2–H2O, and NaCl–CaCl2–H2O. Geochim. Cosmochim. Acta 54, 596–601 (1990).

  21. 21.

    Fagents, S. A. Considerations for effusive cryovolcanism on Europa: the post-Galileo perspective. J. Geophys. Res. 108, 5139 (2003).

  22. 22.

    Ruesch, O. et al. Bright carbonate surfaces on Ceres as remnants of salt-rich water fountains. Icarus 320, 39–48 (2019).

  23. 23.

    Blake, S. in Lava Flows and Domes (ed. Fink, J. H.) 88–126 (Springer, 1990).

  24. 24.

    Spera, F. J. in Encyclopedia of Volcanoes (ed. Sigurdson, H.) 171–190 (Academic, 2000).

  25. 25.

    Shields, A. Application of Similarity Principles and Turbulence Research to Bed-Load Movement (Mitteilungen der Preussischen Versuchsanstalt fur Wasserbau und Schiffbau, 1936).

  26. 26.

    Sori, M. M. et al. The vanishing cryovolcanoes of Ceres. Geophys. Res. Lett. 44, 1243–1250 (2017).

  27. 27.

    Sori, M. M. et al. Cryovolcanic rates on Ceres revealed by topography. Nat. Astron. 2, 946–950 (2018).

  28. 28.

    Marchi, S. et al. An aqueously altered carbon-rich Ceres. Nat. Astron. 3, 140–145 (2019).

  29. 29.

    Neveu, M. & Desch, S. J. Geochemistry, thermal evolution, and cryovolcanism on Ceres with a muddy ice mantle. Geophys. Res. Lett. 42, 10,197–10,206 (2015).

  30. 30.

    Kargel, J. S. Cryovolcanism on the icy satellites. Earth Moon Planets 67, 101–113 (1995).

  31. 31.

    Krieger, I. M. & Dougherty, T. J. A mechanism for non-newtonian flow in suspensions of rigid spheres. Trans. Soc. Rheol. 111, 137–152 (1959).

  32. 32.

    Sisko, A. W. The flow of lubricating greases. Ind. Eng. Chem. 50, 1789–1792 (1958).

  33. 33.

    Mosegaard, K. & Tarantola, A. Monte Carlo sampling of solutions to inverse problems. J. Geophys. Res. 100(B7), 12431–12447 (1995).

  34. 34.

    Metropolis, N., Rosenbluth, A. W., Rosenbluth, M. N., Teller, A. H. & Teller, E. Equation of state calculations by fast computing machines. J. Chem. Phys. 21, 1087–1092 (1953).

  35. 35.

    Hastings, W. K. Monte Carlo sampling methods using Markov chains and their applications. Biometrika 57, 97–109 (1970).

  36. 36.

    Schubert, G., Turcotte, D. L. & Olson, P. Mantle Convection in the Earth and Planets (Cambridge Univ. Press, 2001).

  37. 37.

    Yomogida, K. & Matsui, T. Multiple parent bodies of ordinary chondrites. Earth Planet. Sci. Lett. 68, 34–42 (1984).

  38. 38.

    Chase, M. W. Jr NIST-JANAF Thermochemical Tables 4th edn (Monograph 9) (National Institute of Standards and Technology, 1998).

  39. 39.

    Dorsey, N. E. Properties of Ordinary Water‐Substance in All Its Phases: Water‐Vapor, Water, and All the Ices (ACS Monograph Series 81, Reinhold Publishing Corporation, 1940).

  40. 40.

    Ramires, M. L. V. et al. Standard reference data for the thermal conductivity of water. J. Phys. Chem. Ref. Data 24, 1377–1381 (1995).

  41. 41.

    Klinger, J. Influence of a phase transition of ice on the heat and mas balance of comets. Science 209, 271–272 (1980).

  42. 42.

    Grindrod, P. M. et al. The long-term stability of a possible aqueous ammonium sulfate ocean inside Titan. Icarus 197, 137–151 (2008).

  43. 43.

    Shoji, D. & Kurita, K. Compositional diapirism as the origin of the low-albedo terrain and vaporization at mid latitude on Ceres. J. Geophys. Res. 119, 2457–2470 (2014).

  44. 44.

    Hilairet, N. et al. High-pressure creep of serpentine, interseismic deformation, and initiation of subduction. Science 318, 1910–1912 (2007).

  45. 45.

    Dhodapkar, S., Jacobs, K. & Hu, S. in Multiphase Flow Handbook (ed. Crowe, C. T.) Ch. 4 (CRC, 2006).

  46. 46.

    Weisbrod, N., Yechieli, Y., Shandalov, S. & Lensky, N. On the viscosity of natural hyper-saline solutions and its importance: the Dead Sea brines. J. Hydrol. 532, 46–51 (2016).

  47. 47.

    Turian, R. M., Ma, T. W., Hsu, F. L. G. & Sung, D. J. Characterization, settling, and rheology of concentrated fine particulate mineral slurries. Powder Technol. 93, 219–233 (1997).

  48. 48.

    Krieger, I. M. & Dougherty, T. J. A mechanism for non-newtonian flow in suspensions of rigid spheres. Trans. Soc. Rheol. 3, 137–152 (1959).

  49. 49.

    Kruif, C. H., van Iersel, E. M. F., Vrij, A. & Russell, W. B. Hard sphere colloidal dispersions: viscosity as a function of shear rate and volume fraction. J. Chem. Phys. 83, 4717–4725 (1985).

  50. 50.

    Mueller, S., Llewellin, E. W. & Mader, H. M. The rheology of suspensions of solid particles. Proc. R. Soc. A 466, 1201–1228 (2010).

  51. 51.

    Genovese, D. B. Shear rheology of hard-sphere, dispersed, and aggregated suspensions, and filler-matrix composites. Adv. Colloid Interface Sci. 171-172, 1–16 (2012).

  52. 52.

    Tadros, T. F. Rheology of Dispersions: Principles and Applications (Wiley-VCH, 2010).

  53. 53.

    Darby, R. Chemical Engineering Fluid Mechanics (Dekker, 2001).

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The Dawn spacecraft Operations and Flight teams made the observations possible and are acknowledged for their efforts. O.R. is supported by an appointment to the ESA Research Fellow Programme at the European Space and Technology Centre.

Author information

O.R. conceived the study and performed the rheology analysis. A.G. developed the mascon model, and performed the gravity and MCMC analyses. W.N. performed the mantle convection analysis. L.C.Q. and J.C.C.-R. contributed to the development of the rheological and compositional concepts. C.A.R., C.T.R and M.T.Z. contributed to the discussion of the results. O.R. and A.G. wrote the initial manuscript draft. All authors edited the manuscript and approved the final version.

Competing interests

The authors declare no competing interests.

Correspondence to Ottaviano Ruesch.

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Fig. 1: Colocation of volcanic dome and isostatic gravity anomaly.
Fig. 2: Gravity anomaly residuals for two solutions of the mascon analysis.
Fig. 3: Mascon parameters shown as histograms of the final ensemble of solutions.
Fig. 4: Constraints on the properties of the ascending fluid.