Kattenhorn, S.A., Hurford, T.A. (2009)

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Tectonics of Europa.


In: Europa, Pappalardo, R.T., McKinnon, W.B., Khurana, K., eds, University of Arizona Press, 199-236.

Europa has experienced significant tectonic disruption over its visible history. The description, interpretation, and modeling of tectonic features imaged by the Voyager and Galileo missions has resulted in significant developments in four key areas addressed in this chapter: (1) The characteristics and formation mechanisms of the various types of tectonic features; (2) The driving force behind the tectonics; (3) The geological evolution of its surface; and (4) The question of ongoing tectonics. We elaborate upon these themes, focusing on the following elements: (1) The prevalence of global tension, combined with the inherent weakness of ice, has resulted in a wealth of extensional tectonic features. Crustal convergence features are less obvious but are seemingly necessary for a balanced surface area budget in light of the large amount of extension. Strike-slip faults are relatively common but may not imply primary compressive shear failure, as the constantly changing nature of the tidal stress field likely promotes shearing reactivation of preexisting cracks. Frictional shearing and heating thus contributed to the morphologic and mechanical evolution of tectonic features. (2) Many fracture patterns can be correlated with theoretical stress fields induced by diurnal tidal forcing and long-term effects of nonsynchronous rotation of the icy shell; however, these driving mechanisms alone probably cannot explain all fracturing. Additional sources of stress may have been associated with orbital evolution, polar wander, finite obliquity, ice shell thickening, endogenic forcing by convection and diapirism, and secondary effects driven by strike-slip faulting and plate flexure. (3) Tectonic resurfacing has dominated the ~40-90 Myr of visible geological history. A gradual decrease in tectonic activity through time coincided with an increase in cryomagmatism and thermal convection in the icy shell, implying shell thickening. Hence, tectonic resurfacing gave way to cryomagmatic resurfacing through the development of broad areas of crustal disruption called chaos. (4) There is no definitive evidence for active tectonics; however, some tectonic features have been noted to postdate chaos. A thickening icy shell equates to a decreased tidal response in the underlying ocean, but stresses associated with icy shell expansion may still sufficiently augment the contemporary tidal stress state to allow active tectonics.

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External link: Science Direct



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Citations:


This paper has been cited in the following 14 works:


Dombard, A.J., Patterson, G.W., Lederer, A.P., Prockter, L.M. 2013. Flanking fractures and the formation of double ridges on Europa. ICARUS 223 (1): 74-81.

Hammond, N.P., Phillips, C.B., Nimmo, F., Kattenhorn, S.A. 2013. Flexure on Dione: Investigating subsurface structure and thermal history. ICARUS 223 (1): 418-422.

Stephan, K., Jaumann, R., Wagner, R. 2013. Geology of Icy Bodies. In: The Science of Solar System Ices. ASTROPHYSICS AND SPACE SCIENCE LIBRARY VOLUME 356: 279-367.

Bland, M.T., McKinnon, W.B. 2012. Forming Europa's folds: Strain requirements for the production of large-amplitude deformation. ICARUS 221 (2): 694-709.

Rhoden, A.R., Wurman, G., Huff, E.M., Manga, M., Hurford, T.A., Manga, M. 2012. Shell tectonics: A mechanical model for strike-slip displacement on Europa. ICARUS 218 (1): 297-307.

Ivanov, M.A., Prockter, L.M., Dalton, B. 2011. Landforms of Europa and selection of landing sites. ADVANCES IN SPACE RESEARCH 48 (4): 661-677.

Jara-OruÉ, H.M., Vermeersen, B.L.A. 2011. Effects of low-viscous layers and a non-zero obliquity on surface stresses induced by diurnal tides and non-synchronous rotation: The case of Europa. ICARUS 215 (1): 417-438.

Johnston, S., Montesi, L. 2011. The diversity of ridges on Europa: Implications for formation. INTERNATIONAL WORKSHOP ON MODELING OF MANTLE CONVECTION AND LITHOSPHERIC DYNAMICS 12: 1-2.

Rampelotto, P.H., 2011. A Mission to Titan, Europa, or Enceladus? JOURNAL OF COSMOLOGY, in press.

Singer, K.N., McKinnon, W.B. 2011. Tectonics on Iapetus: Despinning, respinning, or something completely different? ICARUS 216 (1): 198-211.

Pappalardo, R.T. 2010. Seeking Europa's ocean. In: Barbieri, C., Chakrabarti, S., Coradini, M., Lazzarin, M., Eds, Galileo's Medicean Moons: their impact on 400 years of discovery. PROCEEDINGS IAU SYMPOSIUM 269: 101-114.

Prockter, L.M., Lopes, R.M.C., Giese, B., Jaumann, R., Lorenz, R.D., Pappalardo, R.T., Patterson, G.W., Thomas, P.C., Turtle, E.P., Wagner, R.J., 2010. Characteristics of icy surfaces. SPACE SCIENCE REVIEWS 153 (1-4): 63-111.

Rhoden, A.R., Hurford, T.A., Manga, M. 2010. Strike-slip fault patterns on Europa: Obliquity or polar wander? ICARUS 211: 636-647.

Schultz, R.A., Hauber, E., Kattenhorn, S.A., Okubo, C.H., Watters, T.R. 2010. Interpretation and analysis of planetary structures. JOURNAL OF STRUCTURAL GEOLOGY 32: 855-875.

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