Off-campus UMass Amherst users: To download campus access dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Dissertations that have an embargo placed on them will not be available to anyone until the embargo expires.

Document Type

Open Access Dissertation

Degree Name

Doctor of Philosophy (PhD)

Degree Program

Geosciences

Year Degree Awarded

2017

Month Degree Awarded

May

First Advisor

Michele L. Cooke

Subject Categories

Geology | Tectonics and Structure

Abstract

This dissertation predicts fracture propagation and interaction within the framework of work optimization. With this approach, fractures are predicted to propagate along the path that optimizes work. This dissertation includes three projects that predict fracture growth using work optimization in varying tectonic environments. The projects build on work completed during my M.S. at UMass, which includes the development of the fracture modeling tool Growth by Optimization of Work (GROW) [McBeck et al., 2016]. GROW simulates fracture propagation, interaction and linkage by iteratively searching for fracture propagation paths that maximize the change in external work done on the system divided by the new fracture area propagated in an increment of growth, ΔWextA. In Ch. 1, I use GROW to simulate fault development in a crustal extensional step over. This investigation of a crustal fault network demonstrates the utility of the work optimization approach in predicting the development and interaction of crustal faults. The analyses investigate the influence of fault geometry and anisotropy on fault propagation and interaction, and the range of highly efficient fault propagation paths in extensional step over configurations. In Ch. 2, I integrate observations from physical and numerical experiments in order to predict the geometry of accretion faults in a numerical simulation of a physical accretion experiment. This analysis is a novel approach to predicting accretion fault geometry, which could complement traditional Coulomb failure criteria. In Ch. 3, I track the evolution of individual components of the energy budget within an accretionary system. This analysis reveals the tradeoffs between competing deformational processes throughout the evolution of accretionary systems. The energy budget provides a framework for directly comparing the energetic contribution or consumption of diverse deformation mechanisms, from frictional sliding to internal host rock deformation.

Share

COinS