Assessing the brittle crust thickness from strike-slip fault segments on Earth, Mars and Icy moons - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Access content directly
Journal Articles Tectonophysics Year : 2021

Assessing the brittle crust thickness from strike-slip fault segments on Earth, Mars and Icy moons

Abstract

Segment lengths along major strike-slip faults exhibit a size dependency related to the brittle crust thickness. These segments result in the formation of the localized “P-shear” deformation crossing and connecting the initial Riedels structures (i.e. en-echelon fault structures) which formed during the genesis stage of the fault zone. Mechanical models show that at all scales, the geometrical characteristics of the Riedels exhibit dependency on the thickness of the brittle layer. Combining the results of our mechanical discrete element model with several analogue experiments using sand, clay and gypsum, we have formulated a relationship between the orientation and spacing of Riedels and the thickness of the brittle layer. From this relationship, we derive that for a pure strike-slip mode, the maximum spacing between the Riedels is close to three times the thickness of the layer. For a transtensional mode, as the extensive component becomes predominant, the spacing distance at the surface becomes much smaller than the thickness. Applying this relationship to several well-characterized strike-slip faults on Earth, we show that the predicted brittle thickness is consistent with the seismogenic depth. Supposing the ubiquity of this phenomenon, we extented this relationship to characterize en-echelon structures observed on Mars, in the Memnonia region located West of Tharsis. Assuming that the outer ice shells of Ganymede, Ence-ladus and Europa, exhibit a brittle behavior, we suggest values of the corresponding apparent brittle thicknesses.
Fichier principal
Vignette du fichier
S0040195121000639.pdf (1.33 Mo) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

hal-03158574 , version 1 (10-03-2023)

Licence

Identifiers

Cite

Frédéric-Victor Donzé, Yann Klinger, Viviana Bonilla-Sierra, Jérôme Duriez, Liqing Jiao, et al.. Assessing the brittle crust thickness from strike-slip fault segments on Earth, Mars and Icy moons. Tectonophysics, 2021, 805, pp.1-23. ⟨10.1016/j.tecto.2021.228779⟩. ⟨hal-03158574⟩
111 View
44 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More