The idea for a book on anorthosites came to me in January of 1986 while returning to Houston after holiday festivities in Dallas. The original idea was a review paper on anorthosites, but by the time I reached Houston, the subject material I contemplated induding was obviously too extensive for a single paper. The Director of the Lunar and Planetary Institute, Kevin Burke, was receptive to the idea of a book, and suggested that I contact Peter Wyllie, who serves as Editor of the Springer-Verlag series Minerals and Rocks. This effort, which I originally expected would take about a year, has taken nearly 6. I have many excuses- indolence, moving to another continent, other commitments, etc.-but the basic truth is that writing a book is much larger an undertaking than can be anticipated. Many people are aware of this, and I was duly forewarned. . But why write a book on anorthosites? This is a very good question, which I have considered from many angles. One rationale can be expressed in terms of a comparison between anorthosite and basalt. A first-order understanding of basalt genesis has been extant for many years. By contrast, there is little agreement about the origin of anorthosite. There are good reasons for studying and writing about basalt: it is the most abundant rock type on the Earth's surface, and is also plentiful on the surfaces of the other terrestrial planets.

Klappentext

The origin of anorthosites is a major unsolved petrogeneticproblem in igneous petrology. For most of the numerous typesof anorthosite that occur on Earth (and on other planets aswell), we cannot agree as to their parental magma composi-tions, the sources and methods of generation of these mag-mas, the mechanism of plagioclase accumulation, or theirtectonic setting. This book represents the only comprehensi-ve review of what is known and unknown about all anorthositetypes, both terrestrial and extraterrestrial. Descriptive,interpretative, and speculative information is given for alltypes of anorthosite, including therecently discovered an-orthositic meteorites from the Moon. The book is generouslyillustrated, with photographs and diagrams at all scalesfromphotomicrographs to satellite imagery. There are ex-haustive tabulations ofterrestrial anorthosite occurrences,giving their important attributes. A final chapter containsa synthesis of current knowledge and thinking on anorthosi-tes in general, some speculations on their significance inEarth and planetary history, and suggestions for future re-search. This book will be an essential source not only forthose active in anorthosite studies, but also for resear-chers and students interested in the broader aspects ofEarth and planetary history.

Inhalt
1 Introduction.- 1.1 History and Nomenclature.- 1.2 Anorthosite Classification.- 1.3 The Anorthosite Problem.- 1.4 General Structure of this Volume.- 2 Archean Megacrystic Anorthosites.- 2.1 Introduction.- 2.2 General Features and Distribution.- 2.3 Geologic Environment.- 2.4 Form and Structure.- 2.5 Magmatic Textures and Structures.- 2.6 Megacryst-Bearing Mafic Dikes, Sills, and Flows.- 2.7 Metamorphic Textures and Structures.- 2.8 Mineralogy and Petrography.- 2.9 Chemical Composition.- 2.10 Ore Deposits and Metallogeny.- 2.11 Ages and Isotopic Compositions.- 2.12 Descriptions of Anorthosite Occurrences.- 2.13 Origin of Archean Megacrystic Anorthosites.- 2.14 Summary.- 3 Proterozoic Massif-Type Anorthosites.- 3.1 Introduction.- 3.2 Distribution.- 3.3 Geologic Setting.- 3.4 Form and Structure.- 3.5 Lithologies.- 3.6 Magmatic Features.- 3.7 Metamorphic Structures and Textures.- 3.8 Mineralogy.- 3.9 Chemical Composition.- 3.10 Ore Deposits and Metallogeny.- 3.11 Associated Silicic Rocks.- 3.12 Layered Intrusions Related (?) to Massif-Type Anorthosite.- 3.13 Ages and Isotopic Compositions.- 3.14 Descriptions of Selected Anorthosite Bearing Terranes.- 3.15 Petrogenesis of Massif-Type Anorthosites.- 3.16 Tectonic Setting: the Frontier of Anorthosite Research.- 3.17 Summary.- 4 Anorthosites in Layered Mafic Intrusions.- 4.1 Introduction.- 4.2 Stratigraphic Position of Anorthosites.- 4.3 Structural Varieties of Anorthosite.- 4.4 Textural Varieties of Anorthosite.- 4.5 Mineralogy.- 4.6 Chemical Composition.- 4.7 Isotopic Systematics.- 4.8 Petrogenesis.- 4.9 Ore Deposits and Metallogeny.- 4.10 Descriptions of Some Anorthosite-Bearing Layered Mafic Intrusions.- 4.11 Summary.- 5 Anorthosites of Oceanic Settings.- 5.1 Introduction.- 5.2 Anorthosites of the Ocean Basins.- 5.3Anorthosites in Ophiolite Complexes.- 6 Anorthosite Inclusions in Other Igneous Rocks.- 6.1 Introduction.- 6.2 Cognate Inclusions.- 6.3 Xenolithic Inclusions.- 7 Extraterrestrial Anorthosites.- 7.1 Lunar Anorthosites.- 7.2 Anorthositic Meteorites from the Moon.- 7.3 Anorthosites on the Other Terrestrial Planets?.- 7.4 Summary.- 8 Synthesis and Summary.- 8.1 Classification and Characteristics.- 8.2 Petrogenesis.- 8.3 Timing of Anorthosite Formation.- 8.4 Research Frontiers.- References.- Locality Index.