Modeling episodic fluid-release events in the ductile carbonates of the Glarus thrust

Journal Article (Journal Article)

The exposed Glarus thrust displays midcrustal deformation with tens of kilometers of displacement on an ultrathin layer, the principal slip zone (PSZ). Geological observations indicate that this structure resulted from repeated stick-slip events in the presence of highly overpressured fluids. Here we show that the major characteristics of the Glarus thrust movement (localization, periodicity, and evidence of pressurized fluids) can be reconciled by the coupling of two processes, namely, shear heating and fluid release by carbonate decomposition. During this coupling, slow ductile creep deformation raises the temperature through shear heating and ultimately activates the chemical decomposition of carbonates. The subsequent release of highly overpressurized fluids forms and lubricates the PSZ, allowing a ductile fault to move tens of kilometers on millimeter-thick bands in episodic stick-slip events. This model identifies carbonate decomposition as a key process for motion on the Glarus thrust and explains the source of overpressured fluids accessing the PSZ. Key Points Oscillating brittle-ductile deformation processes explained by energy feedbackMultiscale time-space observations in the Glarus thrust explained by one modelThe Glarus thrust exposes spatial patterns of episodic fluid-release slip events

Full Text

Duke Authors

Cited Authors

  • Poulet, T; Veveakis, M; Herwegh, M; Buckingham, T; Regenauer-Lieb, K

Published Date

  • October 28, 2014

Published In

Volume / Issue

  • 41 / 20

Start / End Page

  • 7121 - 7128

Electronic International Standard Serial Number (EISSN)

  • 1944-8007

International Standard Serial Number (ISSN)

  • 0094-8276

Digital Object Identifier (DOI)

  • 10.1002/2014GL061715

Citation Source

  • Scopus