Phoscorites and Carbonatites from Mantle to Mine: the Key Example of the Kola Alkaline Province

Book excerpt: Phoscorites are dark, often very handsome, sometimes economically valuable, magnetite-apatite-silicate rocks, almost always associated with carbonatite. They are key to understanding the longstanding question of how carbonate and carbonate-bearing magmas rise to the crust and the Earths surface. Despite this, they have been given little attention; a search on geological literature databases will produce thousands of references to carbonatite (up to 4125 on Georef) but not more than thirty references to phoscorite. This book goes some way to redress this balance. Over recent years many European and North American scientists have studied Kola rocks in collaboration with Russian colleagues. The idea for this book came from one such project funded by the European organisation, INTAS (Grant No 97-0722). The Kola Peninsula is one of the outstanding areas in the World for the concentration and economic importance of alkaline rocks. However, Russian work on the Kola complexes is still relatively unknown and a particular aim of this book, as well as presenting current research, is to make this knowledge accessible to English language readers. A large exploration programme on Kola alkaline rocks was active from 1950 to 1990 and involved teams of geologists who studied many kilometres of drill core and carried out detailed mineralogical and petrological studies.