Energy budget and propagation of faults via shearing and opening using work optimization

Madden, Elizabeth H.; Cooke, Michele L. and McBeck, Jessica (2017): Energy budget and propagation of faults via shearing and opening using work optimization. In: Journal of Geophysical Research-Solid Earth, Vol. 122, No. 8: pp. 6757-6772

Abstract

We present numerical models of faults propagating by work optimization in a homogeneous medium. These simulations allow quantification and comparison of the energy budgets of fault growth by shear versus tensile failure. The energy consumed by growth of a fault, W-grow, propagating by in-line shearing is 76% of the total energy associated with that growth, while 24% is spent on frictional work during propagation. W-grow for a fault propagating into intact rock by tensile failure, at an angle to the parent fault, consumes 60% of the work budget, while only 6% is consumed by frictional work associated with propagation. Following the conservation of energy, this leaves 34% of the energy budget available for other activities and suggests that out-of-plane propagation of faults in Earth's crust may release energy for other processes, such as permanent damage zone formation or rupture acceleration. Comparison of these estimates of W-grow with estimates of the critical energy release rate and earthquake fracture energy at several scales underscores their theoretical similarities and their dependence on stress drop.

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences
• Subjects: 500 Science > 550 Earth sciences and geology
• ISSN: 2169-9313
• Language: English