Influence of Outcrop Scale Fractures on the Effective Stiffness of Fault Damage Zone Rocks

Autor: W. Ashley Griffith, Pablo F. Sanz, David Pollard
Rok vydání: 2009
Předmět:
Zdroj: Pure and Applied Geophysics. 166:1595-1627
ISSN: 1420-9136
0033-4553
Popis: We combine detailed mapping and microstructural analyses of small fault zones in granodiorite with numerical mechanical models to estimate the effect of mesoscopic (outcrop-scale) damage zone fractures on the effective stiffness of the fault zone rocks. The Bear Creek fault zones were active at depths between 4 and 15 km and localize mesoscopic off-fault damage into tabular zones between two subparallel boundary faults, producing a fracture-induced material contrast across the boundary faults with softer rocks between the boundary faults and intact granodiorite outside the boundary faults. Using digitized fault zone fracture maps as the modeled fault geometries, we conduct nonlinear uniaxial compression tests using a novel finite-element method code as the experimental “laboratory” apparatus. Map measurements show that the fault zones have high nondimensional facture densities (
Databáze: OpenAIRE
Externí odkaz: