Igneous Rocks A Classification and Glossary of Terms 2nd Le Maitre (original) (raw)
Related papers
IGNEOUS ROCKS: A CLASSIFICATION AND GLOSSARY OF TERMS
Decades of field and microscope studies and more recent quantitative geo-chemical analyses have resulted in a vast, and sometimes overwhelming, array of nomenclature and terminology associated with igneous rocks. Under the auspices of the International Union of Geological Sciences (IUGS), a group of petrologists from around the world has laboured for more than 30 years to collate these terms, gain international agreement on their usage, and reassess the methods by which we categorize and name igneous rocks. This book presents the results of their work and gives a complete classification of igneous rocks based on all the recommendations of the IUGS Sub-commission on the Systematics of Igneous Rocks. Revised from the 1st edition (1989), it shows how igneous rocks can be distinguished in the sequence of pyroclastic rocks, carbonatites, melilite-bearing rocks, kalsilite-bearing rocks, kimberlites, lamproites, leucite-bearing rocks, lamprophyres and charnockites. It also demonstrates how the more common plutonic and volcanic rocks that remain can then be categorized using the familiar and widely accepted modal QAPF and chemical TAS classification systems. The glossary of igneous terms has been fully updated since the 1st edition and now includes 1637 entries, of which 316 are recommended by the Subcommission, 312 are regarded as local terms, and 413 are now considered obsolete. Incorporating a comprehensive list of source references for all the terms included in the glossary, this book will be an indispensable reference guide for all geologists studying igneous rocks, either in the field or the laboratory. It presents a standardized and widely accepted naming scheme that will allow geologists to interpret terminology found in the primary literature and provide formal names for rock samples based on petrographic analyses. Work on this book started as long ago as 1958 when Albert Streckeisen was asked to collaborate in revising Paul Niggli's well-known book Tabellen zur Petrographie und zum Gesteinbestimmen (Tables for Petrography and Rock Determination). It was at this point that Streckeisen noted significant problems with all 12 of the classification systems used to identify and name igneous rocks at that time. Rather than propose a 16th system, he chose instead to write a review article outlining the problems inherent in classifying igneous rocks and invited petrologists from around the world to send their comments. In 1970 this lead to the formation of the Subcommission of the Systematics of Igneous Rocks, under the IUGS Commission on Petrology, who published their conclusions in the 1st edition of this book in 1989. The work of this international body has continued to this day, lead by Bruno Zanettin and later by Mike Le Bas. This fully revised 2nd edition has been compiled and edited by Roger Le Maitre, with significant help from a panel of co-contributors.
Igneousrocks AClassificationandGlossaryofTerms Maitre
Decades of field and microscope studies and more recent quantitative geochemical analyses have resulted in a vast, and sometimes overwhelming, array of nomenclature and terminology associated with igneous rocks. Under the auspices of the International Union of Geological Sciences (IUGS), a group of petrologists from around the world has laboured for more than 30 years to collate these terms, gain international agreement on their usage, and reassess the methods by which we categorize and name igneous rocks.
Igneous Rocks and Processes - Robin Gill
Igneous Rocks and Processes, 2010
Preface vii 1. An introduction to magmas and magmatic rocks 1 2. Basalts and related rocks 20 3. Magma differentiation 65 4. Gabbroic rocks 93 5. Ultramafi c and ultrabasic rocks 6. Andesite, dacite and rhyolite 7. How magmas erupt-an introduction to pyroclastic processes and products 8. Granitic rocks 9. Alkali rocks Appendix A-Mineral identifi cation using a polarizing microscope Appendix B-Petrographic calculations Appendix C-Symbols, units and constants used in this book Glossary Answers to exercises Bibliography Index Colour plate section between pp. 214-215 Companion website for this book: wiley.com/go/gill/igneous 1 AGI Glossary of Geology, 2 nd edition 1960. 2 Holmes (1928). 1 Elsewhere, however (p3), the IUGS defi nes volcanic rock as ' an igneous rock with an aphanitic texture, i.e. a relatively fi ne-grained (< 1 mm) rock … '. Rather than adopt this ambiguous usage, the term ' volcanic ' is reserved in this book for its traditional genetic meaning, describing an igneous rock crystallized from magma that erupted at (or very close to) the surface. 2 See www.bgs.ac.uk/bgsrcs/. 3 The optical principles summarized in Appendix A are intended merely as a reminder, not as an introductory course. The following organizations are thanked for permission to reproduce fi gures (the numbers in parentheses) or other material specifi ed:
IUGS Task Group on Igneous Rocks TGIR
2020
1 Sapienza Università di Roma, Italy 2 Université Paris-Sud, Orsay Cedex, France 3 Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences Novosibirsk, Russia 4 Chinese Academy of Science, Beijing, China 5 Cardiff University, UK 6 Universidade do Estado do Rio de Janeiro, Brazil 7 University of Washington, USA 8 Institute of the Earth’s Crust, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia 9 Lakehead University, Thunder Bay, Ontario, Canada 10 Hokkaido University, Japan 11 University of Miami, USA 12 Cardiff University, UK 13 Scott-Smith Petrology Inc., Vancouver, Canada 14 Baranas Hindu University, Varanasi, India 15 University of Johannesburg, South Africa 16 Leeds University, UK 17 Massey University, Palmerston North, New Zealand
Field guides are essential components of both the archaeologist’s and geologist’s toolkits but must also be worth their weight in a pack. This trio of books, all revised from prior editions, has been updated for Wiley-Blackwell’s Geological Field Guide Series, and their subjects are relevant to a sizable proportion of geoarchaeological research: sedimentary and igneous rocks as well as geophysical surveying. The books are touted as pocket-sized guides for use in the field, and indeed they are perfectly sized to fit in the cargo pocket of field pants (one at a time, not all three at once). The potential for useful field guides on the three topics is exciting, and these books are certainly poised to fill notable voids.
SERIES Igneous Rock Associations 10
2009
Komatiites are ultramafic volcanic rocks that occur mainly in Archean and Paleoproterozoic greenstone belts. These olivine-rich rocks are assumed to have crystallized from magmas that have about 28–30 wt% MgO. They are characterized by spinifex texture platy or skeletal crystals of olivine set in a glassy matrix. Chemically, komatiites resemble peridotites and have high MgO but low SiO2, TiO2 (<1 wt%), K2O (<0.5 wt%) and incompatible trace element contents. Most of their compositional variations can be accounted for by olivine fractionation. Komatiites are conventionally considered to be derived from high temperature melts that have eruption temperatures of about 1600EC and are produced by high degrees of anhydrous melting of mantle plumes. The abundance of Archean komatiites, their decrease through the Proterozoic and extreme rarity in the Phanerozoic have been taken as evidence for secular cooling of the mantle. However, the plume model has recently been challenged. In marke...