Basic magmatic rocks make up approximately three-quarters of the crust ofthe present day Earth. Because we can observe and study the volcanic products of present day tectonic regimes comprehensively, we can shed light on ancient tectono-magmatic provinces, and thereby deduce the petrogenesis and evolution of the oldest basic rocks. This is the primary objective of this book. The book was conceived in order to provide a comprehensive review of the basic rocks produced during the first half of the Precambrian, i.e. the Archaean and early Proterozoic, to about 1.8 Ga years ago. Two major...