This review of shear-sense indicators in natural geological deformation structures provides an overview of geological flow and detailed explanations on the use of foliations, stiff inclusions, folds, and veins as indicators of shear-sense. The review's aim is to examine types of flow, and the kinematically significant structures which form in them, from a perspective which should be accessible to all interested geologists.

The 8th International Conference on Basement Tectonics was held in Butte, Montana, August 8-12,1988. Historically, basement tectonics conferences have focused on such topics as reactivation of faults, the influence of basement faults on metallogeny and hyrocarbon accumulation, and the use of geophysical and remote sensing techniques to interpret subsurface and surface geology. The 8th Conference diverged from past conferences in that a unifying theme was selected. Because ancient major terrane or cratonic boundaries are often postulated to be fault zones which are subsequently reactivated, the conference was organized to examine all aspects of ancient continental margins and terrane boundaries and to compare younger (Mesozoic) ones, about which more is known, with older (Paleozoic and Precambrian) ones. Moreover, because the 8th Conference was held in the northwestern United States, a greater emphasis was placed on the Mesozoic margin of western North America and the North American shield. The seven oral sessions and four poster sessions all dealt with aspects of the conference theme: characterization and comparison of ancient continental margins. The organizers extend their thanks to those individuals who graciously consented to serve as moderators for the oral sessions: John M. Bartley, Mark S. Gettings, M. Charles Gilbert, John M. Guilbert, Donald W. Hyndman, William P. Leeman, Robert Mason, and A. Krishna Sinha. The program with abstracts volume was prepared by S. E. Lewis and M. J. Bartholomew.

Microtectonics is the interpretation of small-scale deformation structures in rocks. They are studied by optical microscope and contain abundant information on the history and type of deformation and metamorphism in a rock and are therefore used by most geologists to obtain data for large-scale geological interpretations. This advanced textbook contains a large number of photographs and explanatory drawings, special chapters on related techniques, a chapter on microgauges and a simple, non-mathematical treatment of continuum mechanics with practical examples. Special terms are explained in boxes. This textbook is suited for independent use during optical studies on microstructures as a reference manual and as a manual for short courses.

Atlas of Structural Geology features a broad and inclusive range of high-quality meso- and micro-scale full-color photographs, descriptions, and captions related to the deformation of rocks and geologic structures. It is a multi-contributed, comprehensive reference that includes submissions from many of the world's leading structural geologists, making it the most thorough and comprehensive reference available to the scientific community. All types of structures are featured, including structures related to ductile and brittle shear zones, sigma- and delta-structures, mineral fish, duplexes and trapezoids, shear related folds, and flanking structures in meso- and micro-scales. A stunning collection of the world's most beautiful and arresting geologic structures, the Atlas of Structural Geology is the ideal aid in the retention of key concepts in geology. - Presents more than 250 top-quality, full-color photographs contributed by the world's most respected structural geologists - Features a broad range of morphological variations of geologic structures, making it the most up-to-date and inclusive reference of its kind - Edited by a structural geologist with 14 years of experience in related research and instruction - Aids researchers in developing mathematical and analogue models on the peculiarity and uniqueness of the world's most iconic structures

Study of microstructures is an indispensable component of understanding structural geology of any terrain. A number of ‘new’ microscopic structures such as ‘flanking microstructures’, trapezoid-shaped mineral grains, reversal of ductile shear sense, micro-duplexes, V-pull aparts, and new minerals nucleating inside host minerals have recently been described in individual manuscripts. However, for the sake of brevity, microstructural papers cannot show all possible variation in their morphology. The proposed book aims to present these structures with attractive colour photographs. Each photomicrograph will have a comprehensive caption. The book also presents grain boundary migration, boudins, symptoms of metamorphic retrogression, and how well known shear sense indicators (S-C fabrics, mineral fish etc.) vary in morphology in serial-sections. The target audience is for graduate and postgraduate geosciences students and researchers of structural geology.

This book is a systematic guide to the recognition and interpretation of deformation microstructures and mechanisms in minerals and rocks at the scale of a thin section. Diagnostic features of microstructures and mechanisms are emphasized, and the subject is extensively illustrated with high-quality color and black and white photomicrographs, and many clear diagrams. After introducing three main classes of deformation microstructures and mechanisms, low- to high-grade deformation is presented in a logical sequence in Chapters 2 to 5. Magmatic/submagmatic deformation, shear sense indicators, and shock microstructures and metamorphism are described in Chapters 6 to 8, which are innovative chapters in a structural geology textbook. The final chapter shows how deformation microstructures and mechanisms can be used quantitatively to understand the behavior of the earth. Recent experimental research on failure criteria, frictional sliding laws, and flow laws is summarized in tables, and palaeopiezometry is discussed. Audience: This book is essential to all practising structural and tectonic geologists who use thin sections, and is an invaluable research tool for advanced undergraduates, postgraduates, lecturers and researchers in structural geology and tectonics.

Mylonites form in response to high rates of strain within deep ductile shear zones, which are the extensions at depth of surface faults, thrusts and fault breccias, They can have many different mineralogical compositions and are therefore defined on their textural appearance. This atlas provides high definition images of a large number of different mylonites allowing students and geologists to correctly classify them with greater ease. It also provides insights into the interpretation of mylonitic fabrics to answer questions such as; from what type of rock did this mylonite derive? What were the metamorphic circumstances during mylonitization? What was the intensity of deformation?, and What was the sense of shear? This book will complement the very successful textbook "Microtectonics" by Passchier and Trouw.

The elucidation of the mechanisms and kinematics of shear zone deformation, at both local and regional scales, is the subject of a great deal of interest to scientists in the hydrocarbon industry, in seismology, and in structural geology more generally. This book comprises a collection of five theoretical and twelve regional contributions to the subject from a number of leading researchers in the field, with particular emphasis on work carried out in the Indian subcontinent. The book will be invaluable to advances students and researchers involved in the kinematics of shear.

Although there are numerous publications on the geology of high-grade gneiss terrains, few descriptions exist of how to map and carry out structural analysis in these terrains. Textbooks on structural geology concentrate on technIques appli cable to low-grade terrains. Geologists who have no experience of mapping high-grade gneisses are often at a loss as to how to apply techniques to high grade rocks that were developed for low to medium grade metamorphic terrains. Any study of deep crustal processes and their development through time should begin with examination of the primary data source - outcrops of high grade metamorphic terrains. We feel that the urge to apply advanced techniques of fabric analysis, petrology, geochemistry, isotope geochemistry and age deter mination to these rocks often results in brief sampling trips in which there is little, if any analysis of the structural and metamorphic history revealed by outcrop patterns. Many studies of the metamorphic petrology and geochemistry of high-grade gneiss terrains make ineffective use of available field data, often because the authors are unaware of structural complexities and of the ways to recognise and use them. This is unfortunate, because much data can be collected in the field at minimal cost that cannot easily, if at all, be obtained from material in the laboratory. The primary igneous or sedimentary nature of a rock, the relative age of intrusive veins, and the sequence of deformation that they under went, can usually best be determined by straightforward observation in the field.

Proterozoic Orogens of India: A Critical Window to Gondwana provides a unique opportunity to understand a cross-section of the well-exposed and best-studied part of Earth's crust and the processes of continental collision. It covers pulses of reworking processes and their impact on magmatism, metamorphism and deformational history of Proterozoic orogens vis-à-vis the supercontinental formation. The details of structural architecture, crustal blocks, shear zone systems, magmatism, metamorphism, geochemical and isotopic signatures, mineralization and tectonic models of all the Proterozoic orogens of India are discussed along with excellent illustrations reflecting the field-based, multi-scale structural and geological data sets.The spatial distribution, geometry, kinematics and transpressional strain of the shear zone systems (mostly suture zones), which are critical to all conceptual models dealing with tectono-metamorphic history of Proterozoic orogens of India, are also covered. The book summarizes and integrates the state-of -the art understanding of the structural architecture, lithological assemblages, petrological, geochemical, geochronological and geophysical aspects of the Proterozoic orogens of India. - Includes a much needed state-of-the-art tectonic summary of the voluminous data that has emerged from the Protrozoic orogens of India in the last 2-3 decades - Authored by a well-established expert with more than 30 years of experience in the field based, multi-scale structural geological studies of the ancient orogens of India - Covers up-to-date reviews and models of Proterozoic orogens developed in the Indian shield over the past 2.5 billion years of Earth history