Deformation Microstructures and Mechanisms in Minerals and Rocks

by Blenkinsop, Tom G.

• ISBN13: 9780412734809
• ISBN10: 041273480X
• Format: Hardcover
• Copyright: 1996-07-01
• Publisher: Chapman & Hall

Summary

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.

Table of Contents

Acknowledgements
Symbols, Abbreviations and Units
Introduction and Terminology	p. 1
Cataclasis	p. 7
Fundamental cataclastic deformation mechanisms	p. 7
Microcracks	p. 10
Microfaults	p. 17
Deformations bands	p. 18
Distributed cataclasis and cataclastic flow	p. 18
Gouge zone microstructures	p. 19
Microfracture surface features	p. 19
Crystallographic fabrics	p. 22
Pre-lithification deformation microstructures and mechanisms	p. 22
Pseudotachylites and frictional melting	p. 22
Diffusive Mass Transfer by Solution	p. 24
Fundamental deformation mechanisms of diffusive mass transfer by solution	p. 24
Grain surface solution textures	p. 25
Indenting, truncating and interpenetrating grain contacts	p. 25
Strain caps	p. 27
Microstylolites	p. 27
Diffusive mass transfer and cleavage	p. 28
Grain surface deposition textures	p. 30
Overgrowths, porosity reduction, pressure shadows and fringes, and mica beards	p. 32
Grain shape fabrics	p. 33
Fluid inclusion planes	p. 33
Microveins	p. 35
Intracrystalline Plasticity	p. 39
Fundamental mechanisms of intracrystalline plasticity	p. 39
Deformation twins	p. 39
Undulatory extinction	p. 41
Intracrystalline deformation bands, kink bands and subgrains: Recovery	p. 41
Deformation lamellae	p. 47
Grain shape fabrics and ribbon grains	p. 47
New grains, core and mantle structure: Dynamic recrystallization	p. 47
Crystallographic fabrics	p. 50
Diffusive Mass Transfer and Phase Transformations in the Solid State	p. 52
Fundamental deformation mechanisms of solid state diffusive mass transfer and phase transformations	p. 52
Grain shape fabrics and ribbon grains	p. 52
Foam texture, static and secondary recrystallization	p. 54
Decussate texture	p. 54
Porphyroblasts and inclusion trails	p. 54
Reaction rims, relict minerals, coronas and symplectites	p. 57
Chemical zoning	p. 57
Solid state phase transformation microstructures	p. 57
Superplasticity	p. 57
Magmatic and Sub-magmatic Deformation	p. 59
Fundamental deformation mechanisms and microstructures in rocks containing melt	p. 59
Mesoscopic evidence for magmatic and sub-magmatic flow	p. 60
Magmatic microstructures	p. 62
Sub-magmatic microstructures	p. 62
Other microstructures	p. 63
Non-magmatic deformation	p. 63
Microstructural Shear Sense Criteria	p. 65
Curved foliation	p. 66
Oblique foliations and shape preferred orientations	p. 66
Porphyroclast systems	p. 67
S-, C- and C'-fabrics	p. 70
Pressure shadows and fringes	p. 73
Mica fish	p. 74
Porphyroblast internal foliations	p. 75
Crystallographic fabrics	p. 75
Asymmetric microboudins	p. 76
Asymmetric microfolds and rolling structures	p. 77
Shear sense criteria in rocks containing melt	p. 77
Shear sense criteria for faults	p. 79
Shock-induced microstructures and shock metamorphism	p. 80
Shock mechanisms	p. 80
Microfractures	p. 80
Planar Deformation Features (PDFs)	p. 81
Mosaicism	p. 82
Diaplectic glass	p. 83
High pressure polymorphs of quartz - Coesite and stishovite	p. 83
Lechatelierite	p. 83
Tectites, microtectites and spherules	p. 84
Shock barometry and thermometry	p. 85
Calibration of shock pressures from microstructures	p. 85
Diagnostic impact microstructures	p. 88
From Microstructures to Mountains: Deformation Microstructures, Mechanisms and Tetonics	p. 90
Failure criteria	p. 90
Pore fluid pressure and faulting	p. 91
Fracture mechanics and failure criteria	p. 91
Frictional sliding laws	p. 91
Flow laws	p. 92
Polymineralic deformation	p. 94
Deformation mechanism maps	p. 97
Lithospheric strength envelopes	p. 97
Palaeopiezometry	p. 98
Geothermobarometry	p. 104
References	p. 107
Index	p. 127
Color Plate Section	p. 132
Table of Contents provided by Blackwell. All Rights Reserved.