structural geology, propagation mechanics and - Stanford School of ...

was performed by me. The ideas expressed were developed in collaboration with my co-
authors, principally David Pollard and secondarily John Rudnicki of Northwestern
University. The embedded-layer model analysis was originated by Rudnicki. The Eshelby
code was generously provided by Pradeep Sharma of the University of Houston, and
adapted for my use by fellow student Ole Kaven. The boundary element code was written
to my specifications by another fellow student, Gaurav Chopra, in close consultation with
Pollard and with substantial input from me. This paper was published in the November
2005 issue of Journal of Geophysical Research (v. 110, n. B11).
Chapter 3 represents an additional fruit of my collaboration with John Rudnicki, who
had conceived of an energy-release analysis for compaction-band propagation, but was
lacking a convincing physical context in which to frame it. As a result of my work with
him on Chapter 2, he came around to the view that his theoretical model could and should
be grounded primarily in field observations rather than in experimental results, which I
contend produce a phenomenology largely distinct from CB formation in nature. This
subtle feat of scientific diplomacy helped to pierce a somewhat insular and
counterproductive feedback loop between theorists and experimentalists working on
compaction localization. I am the second author after Rudnicki on this paper, and
contributed extensive rewrites and editing (both technical and grammatical) to
fundamentally recast the paper as outlined above. I also conducted targeted fieldwork in
the Valley of Fire to produce the second figure of two that appears in the manuscript. As
always, substantial credit is due David Pollard for his guidance and editing. This succinct
contribution, an important step toward establishing a stress/strain/strength activation limit
for compaction propagation in sandstone, was published in the second August 2005 issue
of Geophysical Research Letters (v. 32, n. 16).
Chapter 4 takes the anticrack model for CBs developed in Chapter 2 and applies it
through the boundary element method (BEM) code (also introduced in Chapter 2) to
investigate the mechanics of CB propagation, interaction and pattern development in the
Aztec sandstone. The scientific premise behind this preliminary draft manuscript is that
all the various 2-D patterns of CB interaction revealed in outcrop express the same
fundamental mechanism of propagation. I attempt to recreate some simple diagnostic
patterns—in-plane propagation, “zig-zag” and anastamosing propagation instability and
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