The motivation for this volume came from the idea that the Precambrian is the key, both to the present, and to the understanding of the Earth as a whole. The Precambrian constitutes about 85% of Earth's history, and of that, about 3.75 billion years of Precambrian time, represented by rocks, are accessible to geoscientists. Ancient atmospheric and environmental conditions can be traced back to the time when the Earth was only about 250 million years old. Precambrian rocks supply almost 75% of...