- The Washington Times - Friday, December 3, 2010

THE PLANET IN A PEBBLE: A JOURNEY INTO EARTH’S DEEP HISTORY
By Jan Zalasiewicz
Oxford University Press, $27.95 256 pages

 

Wonderment about the origin of Earth’s basic material is satisfied with clarity and conversational prose in “The Planet in a Pebble: A Journey Into Earth’s Deep History” by Jan Zalasiewicz. This book is a concise, articulate overview of the basic and dynamic field of geology, especially ancient or “paleo-“geology. Mr. Zalasiewicz demonstrates in an accessible, engaging manner that a typical pebble of slate found on a beach in Wales, like most any stone you would encounter anywhere, is “truly a microcosm of the Universe.”

The grandeur of time, matter and dynamics is the overarching message as the story of the formation of the humble Welsh stone unfolds. The book explores such fundamentals of physics as energy, mass, pressure and gravity by incorporating these concepts into the tale of the emerging pebble. Theories of major events and conditions of Earth’s early history like the origin of the universe, the formation and explosion of stars, the coalescence of stellar matter into planets, the spectacular appearance of the moon and the inception, composition and dynamics of our geosphere, hydrosphere, atmosphere and biosphere are skillfully explicated.

From a scholastic perspective, college educators in the quantitative and natural sciences often search for methods and materials to motivate and engage their students in subject matter that can frequently be tedious to non-science majors. Here in this compact book, the search ends. The book outlines the ultimate “life”-cycle analysis of a typical rock - from conception to gestation to birth to discovery to eventual decay - in a logical, understandable way. Throughout the book, instructors will find plenty of interesting details of a pebble-in-progress to “excavate” for use in classroom instruction. Color plates, black-and-white photographs and clear line drawings add to the appeal as well as the explanatory power of the book.

Close attention is paid not only to what is known or surmised from the best scientific minds and techniques available, but also to areas where the next generation of geological investigators can make their mark. And, Mr. Zalasiewicz reveals the reality of contemporary scientific practice with reflections such as: “It is sobering to recall that we only partly understand the functioning of our modern world, where sea and land and atmosphere can be continually monitored, sampled, and analysed,” “science is the art of the possible” and, more specifically, “[f]ield geology is the ultimate forensic science, the art of the possible, where one combines as much evidence as one can get hold of, with as much ingenuity in analysing it as one can muster - and also with a keen sense of the limitations of one’s deductions.”

Regarding the best minds and techniques, the book unearths plenty of examples of the “models” used in paleogeology. (A scientific model can be generally defined as a tentative representation of an observation based on an interpretation from available information.) For pebble formation, models that are discussed help to explain such challenges as the role played by oxygen-rich versus oxygen-deficient environments and the formation of tiny, intricate fossil impressions and mineral depositions.

Far from being a laborious science textbook, “The Planet in a Pebble” is a brief, refreshing and unintimidating labor of love from a field-experienced scientist - a work that could even capture the imaginations of some uninitiated students. For educators, the book would serve nicely as a supplemental text to a course in introductory geology or earth and space science. Instructors will also find this book to be a valuable tool to sharpen their own understanding of the grand process that produces a single, ordinary stone from multiple elements over an extraordinary amount of time. And, with the holidays just ahead, you or the earth-science professional or college student in your orbit might enjoy some enlightening reading during the long winter break.

Anthony J. Sadar is a certified consulting meteorologist and an adjunct associate professor at Geneva College in Beaver Falls, Pa., and part-time lecturer at Penn State.