Earth-prints repository, logo   DSpace

About DSpace Software
|earth-prints home page | roma library | bologna library | catania library | milano library | napoli library | palermo library
Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/484

Authors: Bizzarri, A.*
Cocco, M.*
Title: A thermal pressurization model for the spontaneous dynamic rupture propagation on a 3–D fault: Part II – Traction evolution and dynamic parameters
Issue Date: 3-Jun-2005
Keywords: Thermal pressurization
Frictional heating
Abstract: We investigate the dynamic traction evolution within the cohesive zone during the spontaneous propagation of a 3–D earthquake rupture governed by slip weakening or rate- and state-dependent constitutive laws and accounting for thermal pressurization effects. The analytical solutions as well as temperature and pore pressure evolutions are discussed in a companion paper (Bizzarri and Cocco, 2005b). Our numerical experiments reveal that frictional heating and thermal pressurization modifies traction evolution. The breakdown stress drop, the characteristic slip weakening distance and the breakdown work (i.e., fracture energy) depend on the slipping zone thickness (w) and hydraulic diffusivity ( ω). Thermally activated pore pressure changes caused by frictional heating yield temporal variations of the effective normal stress acting on the fault plane. In the framework of rate- and state-dependent friction, these thermal perturbations modify both the effective normal stress and the friction coefficient. Breakdown stress drop, slip weakening distance and specific breakdown work (J/m 2 ) increases for decreasing values of hydraulic diffusivity and slipping zone thickness. We propose scaling relations to evaluate the effect of w and ω on these physical parameters. We have also investigated the effects of choosing different evolution laws for the state variable as well as the porosity evolution during the breakdown time. Our simulations point out that thermal pressurization modifies the shape of the traction evolution as a function of slip. For particular configurations, the traction versus slip curves display a gradual and continuum weakening for increasing slip: in these cases, the definition of a minimum residual stress and the slip weakening distance become meaningless.
Appears in Collections:Manuscripts
Manuscripts
04.06.03. Earthquake source and dynamics
Papers Published / Papers in press

Files in This Item:

File SizeFormatVisibility
JGR_2005-II_submitted.pdf2.24 MBAdobe PDFView/Open

This item is licensed under a Creative Commons License
Creative Commons


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


Share this record
Del.icio.us

Citeulike

Connotea

Facebook

Stumble it!

reddit


 

Valid XHTML 1.0! ICT Support, development & maintenance are provided by CINECA. Powered on DSpace Software. CINECA