9781334487477 - The Azoic System and Its Proposed Subdivisions (Classic Reprint) de Whitney, J. D. (3 resultados)

PAP. Condición: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condición: New. New Book. Shipped from UK. Established seller since 2000.

Paperback. Condición: New. Print on Demand. This book examines evolving classifications for Canada's Azoic System, a geological period before the Cambrian era. It focuses on how the system was originally divided into two series called Laurentian and Huronian by the Canadian Geological Survey, and how this simple division became increasingly complex over time. The book analyzes these divisions, using evidence from the field and from the work of geologists over more than half a century, to explore their validity. The author points out that the divisions were based on assumptions about rock sequences proposed by Sir William Logan in the mid-19th century, and that these assumptions have not always held up to more recent scrutiny. Through this analysis, this valuable book provides insights into the history, methods, and complexities of geological classification. This book is a reproduction of an important historical work, digitally reconstructed using state-of-the-art technology to preserve the original format. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in the book. print-on-demand item.