Atlas of Migmatites: v. 9: The Canadian Mineralogist Special Publication

Migmatites are highly heterogeneous rocks found in high-grade metamorphic environments; they are commonly encountered in the continental crust. Until now, many geologists have been deterred from working with migmatites because of their complex appearance and an unhelpful non-genetic nomenclature. In his "Atlas of Migmatites", Dr. Edward Sawyer provides genetically based definitions and a system of nomenclature with which it will be possible to describe and map migmatites effectively and to understand how combinations of factors and processes produce a bewildering morphological diversity. Migmatites are produced by partial melting; to aid the reader in the identification of migmatites, the author describes and illustrates microstructures that can be used to infer the presence of melt or a melt-producing reaction. He also describes how geochemical data can be used to infer petrological processes involved in migmatite development. This book includes the results from two decades of research in whole-rock geochemistry, partial melting, microstructural analysis and experimental deformation of partially molten rocks. It contains information from an outcrop through to a grain scale. Exceptionally well illustrated, with 272 colour plates and accompanying detailed captions, the Atlas provides descriptions and analyses of migmatites not previously available. Preamble......Page 12 Acknowledgements......Page 14 1. THE SCOPE OF THIS ATLAS......Page 15 2. GENERAL TERMINOLOGY AND DEFINITIONS NEEDED FOR WORK ON MIGMATITES......Page 16 3. MIGMATITES: THE PROCESSES AND MORPHOLOGIES......Page 22 4. METASOMATISM AND MIGMATITES......Page 35 5. MICROSTRUCTURES IN MIGMATITES......Page 37 6. WHOLE-ROCK GEOCHEMISTRY N MIGMATITE STUDIES......Page 48 7. MIGMATITE-LIKE ROCKS......Page 61 8. WORKING WITH MIGMATITES......Page 67 9. APPENDICES......Page 70 10 REFERENCES......Page 76 A. SOME EXAMPLES OF MIGMATITES......Page 92 B. THE PARTS OF A MIGMATITE......Page 96 C. METATEXITE AND DIATEXITE, THE FIRST-ORDER DIVISION OF MIGMATITES......Page 155 D. SECOND-ORDER MORPHOLOGIES IN MIGMATITES......Page 169 E. OTHER MORPHOLOGIES OF MIGMATITE......Page 238 F. MICROSTRUCTURES CHARACTERISTICOF MIGMATITES......Page 255 G. MIGMATITE-LIKE ROCKS......Page 364 Scope Of This Atlas -- General Terminology And Definitions Needed For Work On Migmatites -- Migmatites: The Processes And Morphologies -- Metasomatism And Migmatites -- Microstructures In Migmatites -- Whole-rock Geochemistry In Migmatite Studies -- Migmatite-like Rocks -- Working With Migmatites. Edward W. Sawyer. Nrc Monograph Publishing Program--t.p. Verso. Nrc No. 46331--t.p. Verso. Includes Bibliographical References. Issued By: National Research Council Canada. Co-published By: Mineralogical Association Of Canada.