Strain localisation and weakening of the lithosphere during extension
نویسندگان
چکیده
Article history: We explore the sensitivity o Received 1 September 2007 Received in revised form 25 February 2008 Accepted 27 February 2008 Available online 18 March 2008
منابع مشابه
Forming Ganymede’s Grooves: Producing Large-amplitude, Complex Deformation
We numerically simulate the extension of an ice lithosphere under conditions appropriate to the formation of Ganymede’s grooved terrain using a model that permits a decrease in the brittle strength of the ice as strain accumulates. The inclusion of such strain weakening results in increased localization of the surface deformation, producing large amplitude topography with complex deformation st...
متن کاملThe formation of Ganymede’s grooved terrain: Numerical modeling of extensional necking instabilities
Ganymede’s grooved terrain likely formed during an epoch of global expansion, when unstable extension of the lithosphere resulted in the development of periodic necking instabilities. Linear, infinitesimal-strain models of extensional necking support this model of groove formation, finding that the fastest growing modes of an instability have wavelengths and growth rates consistent with Ganymed...
متن کاملRole of orthopyroxene in rheological weakening of the lithosphere via dynamic recrystallization.
For plate tectonics to operate on a terrestrial planet, the surface layer (the lithosphere) must have a modest strength (Earth, ≤ 200 MPa), but a standard strength profile based on olivine far exceeds this threshold value. Consequently, it is essential to identify mechanisms that reduce the strength of the lithosphere on Earth. Here we report results of high-strain laboratory deformation experi...
متن کاملNew geodynamical model for the regional Tertiary extension during the Zagros orogeny: A transtensional arc?
The Zagros orogeny in Iran is associated with two successive geodynamic events during the Tertiary period, a Paleogene NE-directed regional crustal extension followed by a Miocene NW-directed regional crustal extension and a magmatic flare-up. The current study was undertaken to reanalyze previous structural work developed on the extensional Chapedony metamorphic core complex in Central Iran ex...
متن کاملStress Magnitude, Strain Rate, and Rheology of Extended Middle Continental Crust Inferred from Quartz Grain Sizes in the Whipple Mountains, California
Knowledge of the magnitude of differential stress and strain rate during the formation of mylonitic shear zones in metamorphic ore complexes provides constraints on the mechanical behavior of the middle continental crust during extension. We analyzed the differential flow stress during the mylonitization of quartzofeldspathic rocks in the Whipple Mountains, California, using grain-size piezomet...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008