Exploring A Grand Mystery

Carving Grand Canyon: Evidence, Theory, and Mystery, by Wayne Ranney, is the next logical book to read after the one he co-wrote with Ron Blakey, Ancient Landscapes of the Colorado Plateau. In Ancient Landscapes, the authors describe the environments in which the layers of the Colorado Plateau formed and illustrate those concepts with paleogeographic maps. As you study those maps, you can't help but try to impose the Grand Canyon on them, since it's the feature that best exposes the layers. At what point, you may wonder, does the canyon begin to be carved?

Carving Grand Canyon is the best answer to that question. It narrates the attempt by geologists to formulate a unified theory of how the Grand Canyon formed and how long it took to do so. Once you've started reading it you'll realize that theory is – complicated.

Fortunately, it's also fascinating – a story of rivers and basins, faults and frost wedging, lava flows and karst collapse, personalities and plate tectonics. If you look at a map of the Canyon, from Lee's Ferry to Grand Wash Cliffs, you may suspect that it's not simply a question of how old the Colorado River is (though that's the most pertinent question). It's a question of what else can happen in a region that large, over millions of years during which several unique conditions persist.

One of the most interesting controversies is whether a paleocanyon may have existed, one that continued to be cut down to current levels in parts of the Grand Canyon. The graphic on page 124 beautifully illustrates the argument that a paleocanyon existed in Mesozoic layers above Eastern Grand Canyon that have since eroded away. The relatively new study of karst collapse near the Kaibab Upwarp also sheds some light on the mystery of how the river cut through the southern tip of the upwarp.

This book is for people whose curiosity burns when they look at the Grand Canyon, trained geologists and armchair geologists alike. It is lavishly illustrated with photographs, cross-sections, maps (some of which are paleogeographic), and diagrams that make the text clear and easy to understand. It offers a coherent answer to a question that is far more complicated than it seems. And best of all, it sparks as much curiosity as it satisfies. Buy two copies – one for your reference library, and one to take with you as you explore Grand Canyon, a place with enough wonder to fill a lifetime.

Wayne Ranney: Geologist, Adventurer, and Mapmaster Flash

You may recall that I mentioned, sometime in the recent past, the paleogeographic maps are fabulous. Or you may not. But they are. And what's even more wonderful is that Wayne Ranney, one of the guys behind those afore-mentioned fabulous maps will be speaking at the Heard Museum on Tuesday, December 11, at 1:30 p.m. To 3:00 p.m. He'll be signing copies of his books in our book store afterward. I've posted a review of the book he co-wrote with Ron Blakey, Ancient Landscapes of the Colorado Plateau, which features maps that depict what the Colorado Plateau may have looked like millions and even billions of years ago.

 I will soon be posting a review of Carving Grand Canyon: Evidence, Theories, and Mystery (2nd Edition) which casts light on past and recent arguments about when the Grand Canyon began to form.

 And I look forward to diving into Sedona Through Time, which delves into the formation of one of the most beautiful places on Earth: Oak Creek Canyon.

We have all three titles available at the Heard Museum Book Store, and Mr. Ranney will be signing there after his lecture. Don't miss it!

Paleogeographic Maps Are Fabulous

Think of the nerdiest comic book fan drooling over his favorite graphic novel - that's how I look when I have this book in my hands. As a geology student who lives in Arizona, I have good reason to be such a geek. Every time I visit the Colorado Plateau, I have a thousand questions about how the strata formed. This book answers most of those questions, and illustrates those answers beautifully with diagrams, cross-section charts, photographs, and "paleogeographic maps." Those maps allow the reader to see what the area may have looked like in the past, from the last part of the Precambrian Era, 1.7 billion years ago, through the Mesozoic with its dinosaurs, to the the Cenozoic and our present epoch. If you've ever tried to visualize the supercontinents, or what the Four Corners area may have looked like when it was turned on its side and hugging the equator, the paleogeographic maps are hugely helpful.

Readers who are more interested in archaeology will gain some perspective as to why the ruins in the Southwest are unique - we've got the perfect strata for canyons, creeks, and cliff dwellings. And anyone who would like more background on the geology of their favorite National Park on the Colorado Plateau will find this book handy. As for me, I'm a happy geek pouring over the details of how each layer was formed and where it's exposed in this landscape I love so much. I will refer to this book again again, until it falls apart and I have to get another one. It's money well spent.