"The Franciscan subduction complex formed a long-lived accretionary wedge of Late Jurassic through Oligocene age that fringed the western edge of the North American Cordillera. This volume summarizes absolute finite-strain data from the Franciscan subduction complex and brittle strain data from important faults in and above this complex. Because the Franciscan is generally considered a prototypical sediment-rich subduction complex, its tectonic evolution is important for understanding convergent plate margins, and the results outlined in this volume may have broad implications for other subduction-zone settings."--pub. desc.

This book provides an introduction into the mechanics of faulting in the brittle crust of the Earth. It developed from my annual two-semester course on tectono mechanics for graduate students of engineering geology and of rock engineering at the Technical University of Graz (Austria). In this course, it is not my task to present a broad exposition and geometrical description of geological structures, but rather to focus on the mechanical processes that produce the structures. Although this was also the aim of my former book "Mechanics of Tectonic Faulting - Models and Basic Concepts" (1988, Elsevier), henceforth referred to as MTF, the present book is different in organisation and content, in order to meet the requirements of the courses and to include more recent developments. Instead of following the traditional subdivision into extensional, compressional and strike-slip faulting, the presentation focuses on mechanical aspects of tectonic faulting that are common to various, or even all types of tectonic faults in the brittle regime. In this way, geometrically disparate or dissimilar fault structures may be revealed as closely related by the underlying mechanical process, and complex structures may be better understood. It may be useful to indicate how the chapters in the book are organised. The first three chapters are an introduction to rock mechanics, tailored to applications in geology. It also presents the extremely useful graphical method of Mohr's stress circle, which is freely used throughout the book to keep the mathematics to an absolute minimum.

Earthquake fault zones exhibit hierarchical damage and granular structures with evolving geometrical and material properties. Understanding how repeated brittle deformation form the structures and how the structures affect subsequent earthquakes is a rich problem involving coupling of various processes that operate over broad space and time scales. The diverse state-of-the-art papers collected here show how insight can come from many fields including statistical physics, structural geology and rock mechanics at large scales; elasticity, friction and nonlinear continuum mechanics at intermediate scales; and fracture mechanics, granular mechanics and surface physics at small scales. This volume will be useful to students and professional researchers from Earth Sciences, Material Sciences, Engineering, Physics and other disciplines, who are interested in the properties of natural fault zones and the processes that occur between and during earthquakes.

Beneath Rockfish Gap, one of the lowest elevations along the crest of the Blue Ridge Mountains in Virginia, sits the historic 1858 Blue Ridge Tunnel (BRT). The BRT cuts directly through foliated metabasalts and metasedimentary rocks of the Ediacaran Catoctin Formation and provides a rare 3-dimensional exposure of the Blue Ridge cover sequence on the western limb of the Blue Ridge Anticlinorium. The purpose of this study is to characterize brittle and ductile deformation features in the Catoctin Formation in the BRT to determine their kinematic history. The Catoctin Formation includes a thick sequence of metabasaltic greenstone with thin layers of meta-arkose, sandstone, phyllite and conglomerates that formed between 570-550 Ma. In the arkoses and conglomerates, quartz and perthitic feldspars are the dominant clasts and are typically surrounded by a sericite matrix. Foliation strikes to the NE and dips moderately to the SE with down dip chlorite elongation lineations. Large (1 - 10 m) epidote-rich sandstone boudins typically display top-to-the NW asymmetry. Small, localized folds also occur in the sedimentary units and are tight, overturned NW-verging folds, consistent with NW-directed Neoacadian ductile deformation. Foliation in the greenstone is cut by low-angle top-to-the west shear zones that likely represent the later stages of deformation. Petrographic analysis reveals microstructures formed from dissolution, mass transfer, and volume loss processes under lower greenschist facies conditions. Mineral assemblages indicate that the Catoctin Formation at Rockfish Gap experienced temperatures between 300oC - 400oC. The Catoctin Formation is cut by two dominant fracture sets, a WNW-ESE set and NE-SW set that formed from two separate brittle deformation events; the former from the late Alleghanian Orogeny, and the latter from Atlantic rifting in the early Mesozoic.